Update drivers/staging/bcm/InterfaceInit.h #24

mdminhazulhaque · 2012-10-23T13:16:36Z

Added device ID of ZTE AX326.

This moves ARM over to the asm-generic/unaligned.h header. This has the benefit of better code generated especially for ARMv7 on gcc 4.7+ compilers. As Arnd Bergmann, points out: The asm-generic version uses the "struct" version for native-endian unaligned access and the "byteshift" version for the opposite endianess. The current ARM version however uses the "byteshift" implementation for both. Thanks to Nicolas Pitre for the excellent analysis: Test case: int foo (int *x) { return get_unaligned(x); } long long bar (long long *x) { return get_unaligned(x); } With the current ARM version: foo: ldrb r3, [r0, #2] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 2B], MEM[(const u8 *)x_1(D) + 2B] ldrb r1, [r0, #1] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 1B], MEM[(const u8 *)x_1(D) + 1B] ldrb r2, [r0, #0] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D)], MEM[(const u8 *)x_1(D)] mov r3, r3, asl #16 @ tmp154, MEM[(const u8 *)x_1(D) + 2B], ldrb r0, [r0, #3] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 3B], MEM[(const u8 *)x_1(D) + 3B] orr r3, r3, r1, asl #8 @, tmp155, tmp154, MEM[(const u8 *)x_1(D) + 1B], orr r3, r3, r2 @ tmp157, tmp155, MEM[(const u8 *)x_1(D)] orr r0, r3, r0, asl #24 @,, tmp157, MEM[(const u8 *)x_1(D) + 3B], bx lr @ bar: stmfd sp!, {r4, r5, r6, r7} @, mov r2, #0 @ tmp184, ldrb r5, [r0, #6] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 6B], MEM[(const u8 *)x_1(D) + 6B] ldrb r4, [r0, #5] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 5B], MEM[(const u8 *)x_1(D) + 5B] ldrb ip, [r0, #2] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 2B], MEM[(const u8 *)x_1(D) + 2B] ldrb r1, [r0, #4] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 4B], MEM[(const u8 *)x_1(D) + 4B] mov r5, r5, asl #16 @ tmp175, MEM[(const u8 *)x_1(D) + 6B], ldrb r7, [r0, #1] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 1B], MEM[(const u8 *)x_1(D) + 1B] orr r5, r5, r4, asl #8 @, tmp176, tmp175, MEM[(const u8 *)x_1(D) + 5B], ldrb r6, [r0, #7] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 7B], MEM[(const u8 *)x_1(D) + 7B] orr r5, r5, r1 @ tmp178, tmp176, MEM[(const u8 *)x_1(D) + 4B] ldrb r4, [r0, #0] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D)], MEM[(const u8 *)x_1(D)] mov ip, ip, asl #16 @ tmp188, MEM[(const u8 *)x_1(D) + 2B], ldrb r1, [r0, #3] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 3B], MEM[(const u8 *)x_1(D) + 3B] orr ip, ip, r7, asl #8 @, tmp189, tmp188, MEM[(const u8 *)x_1(D) + 1B], orr r3, r5, r6, asl #24 @,, tmp178, MEM[(const u8 *)x_1(D) + 7B], orr ip, ip, r4 @ tmp191, tmp189, MEM[(const u8 *)x_1(D)] orr ip, ip, r1, asl #24 @, tmp194, tmp191, MEM[(const u8 *)x_1(D) + 3B], mov r1, r3 @, orr r0, r2, ip @ tmp171, tmp184, tmp194 ldmfd sp!, {r4, r5, r6, r7} bx lr In both cases the code is slightly suboptimal. One may wonder why wasting r2 with the constant 0 in the second case for example. And all the mov's could be folded in subsequent orr's, etc. Now with the asm-generic version: foo: ldr r0, [r0, #0] @ unaligned @,* x bx lr @ bar: mov r3, r0 @ x, x ldr r0, [r0, #0] @ unaligned @,* x ldr r1, [r3, #4] @ unaligned @, bx lr @ This is way better of course, but only because this was compiled for ARMv7. In this case the compiler knows that the hardware can do unaligned word access. This isn't that obvious for foo(), but if we remove the get_unaligned() from bar as follows: long long bar (long long *x) {return *x; } then the resulting code is: bar: ldmia r0, {r0, r1} @ x,, bx lr @ So this proves that the presumed aligned vs unaligned cases does have influence on the instructions the compiler may use and that the above unaligned code results are not just an accident. Still... this isn't fully conclusive without at least looking at the resulting assembly fron a pre ARMv6 compilation. Let's see with an ARMv5 target: foo: ldrb r3, [r0, #0] @ zero_extendqisi2 @ tmp139,* x ldrb r1, [r0, #1] @ zero_extendqisi2 @ tmp140, ldrb r2, [r0, #2] @ zero_extendqisi2 @ tmp143, ldrb r0, [r0, #3] @ zero_extendqisi2 @ tmp146, orr r3, r3, r1, asl #8 @, tmp142, tmp139, tmp140, orr r3, r3, r2, asl #16 @, tmp145, tmp142, tmp143, orr r0, r3, r0, asl #24 @,, tmp145, tmp146, bx lr @ bar: stmfd sp!, {r4, r5, r6, r7} @, ldrb r2, [r0, #0] @ zero_extendqisi2 @ tmp139,* x ldrb r7, [r0, #1] @ zero_extendqisi2 @ tmp140, ldrb r3, [r0, #4] @ zero_extendqisi2 @ tmp149, ldrb r6, [r0, #5] @ zero_extendqisi2 @ tmp150, ldrb r5, [r0, #2] @ zero_extendqisi2 @ tmp143, ldrb r4, [r0, #6] @ zero_extendqisi2 @ tmp153, ldrb r1, [r0, #7] @ zero_extendqisi2 @ tmp156, ldrb ip, [r0, #3] @ zero_extendqisi2 @ tmp146, orr r2, r2, r7, asl #8 @, tmp142, tmp139, tmp140, orr r3, r3, r6, asl #8 @, tmp152, tmp149, tmp150, orr r2, r2, r5, asl #16 @, tmp145, tmp142, tmp143, orr r3, r3, r4, asl #16 @, tmp155, tmp152, tmp153, orr r0, r2, ip, asl #24 @,, tmp145, tmp146, orr r1, r3, r1, asl #24 @,, tmp155, tmp156, ldmfd sp!, {r4, r5, r6, r7} bx lr Compared to the initial results, this is really nicely optimized and I couldn't do much better if I were to hand code it myself. Signed-off-by: Rob Herring <[email protected]> Reviewed-by: Nicolas Pitre <[email protected]> Tested-by: Thomas Petazzoni <[email protected]> Reviewed-by: Arnd Bergmann <[email protected]> Signed-off-by: Russell King <[email protected]>

…d reasons We've had some reports of a deadlock where rpciod ends up with a stack trace like this: PID: 2507 TASK: ffff88103691ab40 CPU: 14 COMMAND: "rpciod/14" #0 [ffff8810343bf2f0] schedule at ffffffff814dabd9 #1 [ffff8810343bf3b8] nfs_wait_bit_killable at ffffffffa038fc04 [nfs] #2 [ffff8810343bf3c8] __wait_on_bit at ffffffff814dbc2f #3 [ffff8810343bf418] out_of_line_wait_on_bit at ffffffff814dbcd8 #4 [ffff8810343bf488] nfs_commit_inode at ffffffffa039e0c1 [nfs] #5 [ffff8810343bf4f8] nfs_release_page at ffffffffa038bef6 [nfs] torvalds#6 [ffff8810343bf528] try_to_release_page at ffffffff8110c670 torvalds#7 [ffff8810343bf538] shrink_page_list.clone.0 at ffffffff81126271 torvalds#8 [ffff8810343bf668] shrink_inactive_list at ffffffff81126638 torvalds#9 [ffff8810343bf818] shrink_zone at ffffffff8112788f torvalds#10 [ffff8810343bf8c8] do_try_to_free_pages at ffffffff81127b1e torvalds#11 [ffff8810343bf958] try_to_free_pages at ffffffff8112812f torvalds#12 [ffff8810343bfa08] __alloc_pages_nodemask at ffffffff8111fdad torvalds#13 [ffff8810343bfb28] kmem_getpages at ffffffff81159942 torvalds#14 [ffff8810343bfb58] fallback_alloc at ffffffff8115a55a torvalds#15 [ffff8810343bfbd8] ____cache_alloc_node at ffffffff8115a2d9 torvalds#16 [ffff8810343bfc38] kmem_cache_alloc at ffffffff8115b09b torvalds#17 [ffff8810343bfc78] sk_prot_alloc at ffffffff81411808 torvalds#18 [ffff8810343bfcb8] sk_alloc at ffffffff8141197c torvalds#19 [ffff8810343bfce8] inet_create at ffffffff81483ba6 torvalds#20 [ffff8810343bfd38] __sock_create at ffffffff8140b4a7 torvalds#21 [ffff8810343bfd98] xs_create_sock at ffffffffa01f649b [sunrpc] torvalds#22 [ffff8810343bfdd8] xs_tcp_setup_socket at ffffffffa01f6965 [sunrpc] torvalds#23 [ffff8810343bfe38] worker_thread at ffffffff810887d0 torvalds#24 [ffff8810343bfee8] kthread at ffffffff8108dd96 torvalds#25 [ffff8810343bff48] kernel_thread at ffffffff8100c1ca rpciod is trying to allocate memory for a new socket to talk to the server. The VM ends up calling ->releasepage to get more memory, and it tries to do a blocking commit. That commit can't succeed however without a connected socket, so we deadlock. Fix this by setting PF_FSTRANS on the workqueue task prior to doing the socket allocation, and having nfs_release_page check for that flag when deciding whether to do a commit call. Also, set PF_FSTRANS unconditionally in rpc_async_schedule since that function can also do allocations sometimes. Signed-off-by: Jeff Layton <[email protected]> Signed-off-by: Trond Myklebust <[email protected]> Cc: [email protected]

Printing the "start_ip" for every secondary cpu is very noisy on a large system - and doesn't add any value. Drop this message. Console log before: Booting Node 0, Processors #1 smpboot cpu 1: start_ip = 96000 #2 smpboot cpu 2: start_ip = 96000 #3 smpboot cpu 3: start_ip = 96000 #4 smpboot cpu 4: start_ip = 96000 ... torvalds#31 smpboot cpu 31: start_ip = 96000 Brought up 32 CPUs Console log after: Booting Node 0, Processors #1 #2 #3 #4 #5 torvalds#6 torvalds#7 Ok. Booting Node 1, Processors torvalds#8 torvalds#9 torvalds#10 torvalds#11 torvalds#12 torvalds#13 torvalds#14 torvalds#15 Ok. Booting Node 0, Processors torvalds#16 torvalds#17 torvalds#18 torvalds#19 torvalds#20 torvalds#21 torvalds#22 torvalds#23 Ok. Booting Node 1, Processors torvalds#24 torvalds#25 torvalds#26 torvalds#27 torvalds#28 torvalds#29 torvalds#30 torvalds#31 Brought up 32 CPUs Acked-by: Borislav Petkov <[email protected]> Signed-off-by: Tony Luck <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: H. Peter Anvin <[email protected]>

…d reasons commit 5cf02d0 upstream. We've had some reports of a deadlock where rpciod ends up with a stack trace like this: PID: 2507 TASK: ffff88103691ab40 CPU: 14 COMMAND: "rpciod/14" #0 [ffff8810343bf2f0] schedule at ffffffff814dabd9 #1 [ffff8810343bf3b8] nfs_wait_bit_killable at ffffffffa038fc04 [nfs] #2 [ffff8810343bf3c8] __wait_on_bit at ffffffff814dbc2f #3 [ffff8810343bf418] out_of_line_wait_on_bit at ffffffff814dbcd8 #4 [ffff8810343bf488] nfs_commit_inode at ffffffffa039e0c1 [nfs] #5 [ffff8810343bf4f8] nfs_release_page at ffffffffa038bef6 [nfs] #6 [ffff8810343bf528] try_to_release_page at ffffffff8110c670 #7 [ffff8810343bf538] shrink_page_list.clone.0 at ffffffff81126271 #8 [ffff8810343bf668] shrink_inactive_list at ffffffff81126638 #9 [ffff8810343bf818] shrink_zone at ffffffff8112788f torvalds#10 [ffff8810343bf8c8] do_try_to_free_pages at ffffffff81127b1e torvalds#11 [ffff8810343bf958] try_to_free_pages at ffffffff8112812f torvalds#12 [ffff8810343bfa08] __alloc_pages_nodemask at ffffffff8111fdad torvalds#13 [ffff8810343bfb28] kmem_getpages at ffffffff81159942 torvalds#14 [ffff8810343bfb58] fallback_alloc at ffffffff8115a55a torvalds#15 [ffff8810343bfbd8] ____cache_alloc_node at ffffffff8115a2d9 torvalds#16 [ffff8810343bfc38] kmem_cache_alloc at ffffffff8115b09b torvalds#17 [ffff8810343bfc78] sk_prot_alloc at ffffffff81411808 torvalds#18 [ffff8810343bfcb8] sk_alloc at ffffffff8141197c torvalds#19 [ffff8810343bfce8] inet_create at ffffffff81483ba6 torvalds#20 [ffff8810343bfd38] __sock_create at ffffffff8140b4a7 torvalds#21 [ffff8810343bfd98] xs_create_sock at ffffffffa01f649b [sunrpc] torvalds#22 [ffff8810343bfdd8] xs_tcp_setup_socket at ffffffffa01f6965 [sunrpc] torvalds#23 [ffff8810343bfe38] worker_thread at ffffffff810887d0 torvalds#24 [ffff8810343bfee8] kthread at ffffffff8108dd96 torvalds#25 [ffff8810343bff48] kernel_thread at ffffffff8100c1ca rpciod is trying to allocate memory for a new socket to talk to the server. The VM ends up calling ->releasepage to get more memory, and it tries to do a blocking commit. That commit can't succeed however without a connected socket, so we deadlock. Fix this by setting PF_FSTRANS on the workqueue task prior to doing the socket allocation, and having nfs_release_page check for that flag when deciding whether to do a commit call. Also, set PF_FSTRANS unconditionally in rpc_async_schedule since that function can also do allocations sometimes. Signed-off-by: Jeff Layton <[email protected]> Signed-off-by: Trond Myklebust <[email protected]> Signed-off-by: Ben Hutchings <[email protected]>

Signed-off-by: Vineet Gupta <[email protected]>

asamy · 2012-11-03T12:02:55Z

To get your stuff accepted in the tree, you have to notify them on the mailing list, or send an email to Linus...
See: http://www.tux.org/lkml/

This is an fsfuzzer bug. ->s_journal is set at the end of ext3_load_journal() but we try to use it in the error handling from ext3_get_journal() while it's still NULL. [ 337.039041] BUG: unable to handle kernel NULL pointer dereference at 0000000000000024 [ 337.040380] IP: [<ffffffff816e6539>] _raw_spin_lock+0x9/0x30 [ 337.041687] PGD 0 [ 337.043118] Oops: 0002 [#1] SMP [ 337.044483] CPU 3 [ 337.044495] Modules linked in: ecb md4 cifs fuse kvm_intel kvm brcmsmac brcmutil crc8 cordic r8169 [last unloaded: scsi_wait_scan] [ 337.047633] [ 337.049259] Pid: 8308, comm: mount Not tainted 3.2.0-rc2-next-20111121+ torvalds#24 SAMSUNG ELECTRONICS CO., LTD. RV411/RV511/E3511/S3511 /RV411/RV511/E3511/S3511 [ 337.051064] RIP: 0010:[<ffffffff816e6539>] [<ffffffff816e6539>] _raw_spin_lock+0x9/0x30 [ 337.052879] RSP: 0018:ffff8800b1d11ae8 EFLAGS: 00010282 [ 337.054668] RAX: 0000000000000100 RBX: 0000000000000000 RCX: ffff8800b77c2000 [ 337.056400] RDX: ffff8800a97b5c00 RSI: 0000000000000000 RDI: 0000000000000024 [ 337.058099] RBP: ffff8800b1d11ae8 R08: 6000000000000000 R09: e018000000000000 [ 337.059841] R10: ff67366cc2607c03 R11: 00000000110688e6 R12: 0000000000000000 [ 337.061607] R13: 0000000000000000 R14: 0000000000000000 R15: ffff8800a78f06e8 [ 337.063385] FS: 00007f9d95652800(0000) GS:ffff8800b7180000(0000) knlGS:0000000000000000 [ 337.065110] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 337.066801] CR2: 0000000000000024 CR3: 00000000aef2c000 CR4: 00000000000006e0 [ 337.068581] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 337.070321] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 337.072105] Process mount (pid: 8308, threadinfo ffff8800b1d10000, task ffff8800b1d02be0) [ 337.073800] Stack: [ 337.075487] ffff8800b1d11b08 ffffffff811f48cf ffff88007ac9b158 0000000000000000 [ 337.077255] ffff8800b1d11b38 ffffffff8119405d ffff88007ac9b158 ffff88007ac9b250 [ 337.078851] ffffffff8181bda0 ffffffff8181bda0 ffff8800b1d11b68 ffffffff81131e31 [ 337.080284] Call Trace: [ 337.081706] [<ffffffff811f48cf>] log_start_commit+0x1f/0x40 [ 337.083107] [<ffffffff8119405d>] ext3_evict_inode+0x1fd/0x2a0 [ 337.084490] [<ffffffff81131e31>] evict+0xa1/0x1a0 [ 337.085857] [<ffffffff81132031>] iput+0x101/0x210 [ 337.087220] [<ffffffff811339d1>] iget_failed+0x21/0x30 [ 337.088581] [<ffffffff811905fc>] ext3_iget+0x15c/0x450 [ 337.089936] [<ffffffff8118b0c1>] ? ext3_rsv_window_add+0x81/0x100 [ 337.091284] [<ffffffff816df9a4>] ext3_get_journal+0x15/0xde [ 337.092641] [<ffffffff811a2e9b>] ext3_fill_super+0xf2b/0x1c30 [ 337.093991] [<ffffffff810ddf7d>] ? register_shrinker+0x4d/0x60 [ 337.095332] [<ffffffff8111c112>] mount_bdev+0x1a2/0x1e0 [ 337.096680] [<ffffffff811a1f70>] ? ext3_setup_super+0x210/0x210 [ 337.098026] [<ffffffff8119a770>] ext3_mount+0x10/0x20 [ 337.099362] [<ffffffff8111cbee>] mount_fs+0x3e/0x1b0 [ 337.100759] [<ffffffff810eda1b>] ? __alloc_percpu+0xb/0x10 [ 337.102330] [<ffffffff81135385>] vfs_kern_mount+0x65/0xc0 [ 337.103889] [<ffffffff8113611f>] do_kern_mount+0x4f/0x100 [ 337.105442] [<ffffffff811378fc>] do_mount+0x19c/0x890 [ 337.106989] [<ffffffff810e8456>] ? memdup_user+0x46/0x90 [ 337.108572] [<ffffffff810e84f3>] ? strndup_user+0x53/0x70 [ 337.110114] [<ffffffff811383fb>] sys_mount+0x8b/0xe0 [ 337.111617] [<ffffffff816ed93b>] system_call_fastpath+0x16/0x1b [ 337.113133] Code: 38 c2 74 0f 66 0f 1f 44 00 00 f3 90 0f b6 03 38 c2 75 f7 48 83 c4 08 5b 5d c3 0f 1f 84 00 00 00 00 00 55 b8 00 01 00 00 48 89 e5 <f0> 66 0f c1 07 0f b6 d4 38 c2 74 0c 0f 1f 00 f3 90 0f b6 07 38 [ 337.116588] RIP [<ffffffff816e6539>] _raw_spin_lock+0x9/0x30 [ 337.118260] RSP <ffff8800b1d11ae8> [ 337.119998] CR2: 0000000000000024 [ 337.188701] ---[ end trace c36d790becac1615 ]--- Signed-off-by: Dan Carpenter <[email protected]> Signed-off-by: Jan Kara <[email protected]>

…d reasons commit 5cf02d0 upstream. We've had some reports of a deadlock where rpciod ends up with a stack trace like this: PID: 2507 TASK: ffff88103691ab40 CPU: 14 COMMAND: "rpciod/14" #0 [ffff8810343bf2f0] schedule at ffffffff814dabd9 #1 [ffff8810343bf3b8] nfs_wait_bit_killable at ffffffffa038fc04 [nfs] #2 [ffff8810343bf3c8] __wait_on_bit at ffffffff814dbc2f #3 [ffff8810343bf418] out_of_line_wait_on_bit at ffffffff814dbcd8 #4 [ffff8810343bf488] nfs_commit_inode at ffffffffa039e0c1 [nfs] #5 [ffff8810343bf4f8] nfs_release_page at ffffffffa038bef6 [nfs] #6 [ffff8810343bf528] try_to_release_page at ffffffff8110c670 #7 [ffff8810343bf538] shrink_page_list.clone.0 at ffffffff81126271 #8 [ffff8810343bf668] shrink_inactive_list at ffffffff81126638 #9 [ffff8810343bf818] shrink_zone at ffffffff8112788f torvalds#10 [ffff8810343bf8c8] do_try_to_free_pages at ffffffff81127b1e torvalds#11 [ffff8810343bf958] try_to_free_pages at ffffffff8112812f torvalds#12 [ffff8810343bfa08] __alloc_pages_nodemask at ffffffff8111fdad torvalds#13 [ffff8810343bfb28] kmem_getpages at ffffffff81159942 torvalds#14 [ffff8810343bfb58] fallback_alloc at ffffffff8115a55a torvalds#15 [ffff8810343bfbd8] ____cache_alloc_node at ffffffff8115a2d9 torvalds#16 [ffff8810343bfc38] kmem_cache_alloc at ffffffff8115b09b torvalds#17 [ffff8810343bfc78] sk_prot_alloc at ffffffff81411808 torvalds#18 [ffff8810343bfcb8] sk_alloc at ffffffff8141197c torvalds#19 [ffff8810343bfce8] inet_create at ffffffff81483ba6 torvalds#20 [ffff8810343bfd38] __sock_create at ffffffff8140b4a7 torvalds#21 [ffff8810343bfd98] xs_create_sock at ffffffffa01f649b [sunrpc] torvalds#22 [ffff8810343bfdd8] xs_tcp_setup_socket at ffffffffa01f6965 [sunrpc] torvalds#23 [ffff8810343bfe38] worker_thread at ffffffff810887d0 torvalds#24 [ffff8810343bfee8] kthread at ffffffff8108dd96 torvalds#25 [ffff8810343bff48] kernel_thread at ffffffff8100c1ca rpciod is trying to allocate memory for a new socket to talk to the server. The VM ends up calling ->releasepage to get more memory, and it tries to do a blocking commit. That commit can't succeed however without a connected socket, so we deadlock. Fix this by setting PF_FSTRANS on the workqueue task prior to doing the socket allocation, and having nfs_release_page check for that flag when deciding whether to do a commit call. Also, set PF_FSTRANS unconditionally in rpc_async_schedule since that function can also do allocations sometimes. Signed-off-by: Jeff Layton <[email protected]> Signed-off-by: Trond Myklebust <[email protected]> Signed-off-by: Ben Hutchings <[email protected]>

…d reasons BugLink: http://bugs.launchpad.net/bugs/1035435 commit 5cf02d0 upstream. We've had some reports of a deadlock where rpciod ends up with a stack trace like this: PID: 2507 TASK: ffff88103691ab40 CPU: 14 COMMAND: "rpciod/14" #0 [ffff8810343bf2f0] schedule at ffffffff814dabd9 #1 [ffff8810343bf3b8] nfs_wait_bit_killable at ffffffffa038fc04 [nfs] #2 [ffff8810343bf3c8] __wait_on_bit at ffffffff814dbc2f #3 [ffff8810343bf418] out_of_line_wait_on_bit at ffffffff814dbcd8 #4 [ffff8810343bf488] nfs_commit_inode at ffffffffa039e0c1 [nfs] #5 [ffff8810343bf4f8] nfs_release_page at ffffffffa038bef6 [nfs] torvalds#6 [ffff8810343bf528] try_to_release_page at ffffffff8110c670 torvalds#7 [ffff8810343bf538] shrink_page_list.clone.0 at ffffffff81126271 torvalds#8 [ffff8810343bf668] shrink_inactive_list at ffffffff81126638 torvalds#9 [ffff8810343bf818] shrink_zone at ffffffff8112788f torvalds#10 [ffff8810343bf8c8] do_try_to_free_pages at ffffffff81127b1e torvalds#11 [ffff8810343bf958] try_to_free_pages at ffffffff8112812f torvalds#12 [ffff8810343bfa08] __alloc_pages_nodemask at ffffffff8111fdad torvalds#13 [ffff8810343bfb28] kmem_getpages at ffffffff81159942 torvalds#14 [ffff8810343bfb58] fallback_alloc at ffffffff8115a55a torvalds#15 [ffff8810343bfbd8] ____cache_alloc_node at ffffffff8115a2d9 torvalds#16 [ffff8810343bfc38] kmem_cache_alloc at ffffffff8115b09b torvalds#17 [ffff8810343bfc78] sk_prot_alloc at ffffffff81411808 torvalds#18 [ffff8810343bfcb8] sk_alloc at ffffffff8141197c torvalds#19 [ffff8810343bfce8] inet_create at ffffffff81483ba6 torvalds#20 [ffff8810343bfd38] __sock_create at ffffffff8140b4a7 torvalds#21 [ffff8810343bfd98] xs_create_sock at ffffffffa01f649b [sunrpc] torvalds#22 [ffff8810343bfdd8] xs_tcp_setup_socket at ffffffffa01f6965 [sunrpc] torvalds#23 [ffff8810343bfe38] worker_thread at ffffffff810887d0 torvalds#24 [ffff8810343bfee8] kthread at ffffffff8108dd96 torvalds#25 [ffff8810343bff48] kernel_thread at ffffffff8100c1ca rpciod is trying to allocate memory for a new socket to talk to the server. The VM ends up calling ->releasepage to get more memory, and it tries to do a blocking commit. That commit can't succeed however without a connected socket, so we deadlock. Fix this by setting PF_FSTRANS on the workqueue task prior to doing the socket allocation, and having nfs_release_page check for that flag when deciding whether to do a commit call. Also, set PF_FSTRANS unconditionally in rpc_async_schedule since that function can also do allocations sometimes. Signed-off-by: Jeff Layton <[email protected]> Signed-off-by: Trond Myklebust <[email protected]> Signed-off-by: Ben Hutchings <[email protected]> Signed-off-by: Herton Ronaldo Krzesinski <[email protected]>

…d reasons commit 5cf02d0 upstream. We've had some reports of a deadlock where rpciod ends up with a stack trace like this: PID: 2507 TASK: ffff88103691ab40 CPU: 14 COMMAND: "rpciod/14" #0 [ffff8810343bf2f0] schedule at ffffffff814dabd9 #1 [ffff8810343bf3b8] nfs_wait_bit_killable at ffffffffa038fc04 [nfs] #2 [ffff8810343bf3c8] __wait_on_bit at ffffffff814dbc2f #3 [ffff8810343bf418] out_of_line_wait_on_bit at ffffffff814dbcd8 #4 [ffff8810343bf488] nfs_commit_inode at ffffffffa039e0c1 [nfs] #5 [ffff8810343bf4f8] nfs_release_page at ffffffffa038bef6 [nfs] #6 [ffff8810343bf528] try_to_release_page at ffffffff8110c670 #7 [ffff8810343bf538] shrink_page_list.clone.0 at ffffffff81126271 #8 [ffff8810343bf668] shrink_inactive_list at ffffffff81126638 #9 [ffff8810343bf818] shrink_zone at ffffffff8112788f torvalds#10 [ffff8810343bf8c8] do_try_to_free_pages at ffffffff81127b1e torvalds#11 [ffff8810343bf958] try_to_free_pages at ffffffff8112812f torvalds#12 [ffff8810343bfa08] __alloc_pages_nodemask at ffffffff8111fdad torvalds#13 [ffff8810343bfb28] kmem_getpages at ffffffff81159942 torvalds#14 [ffff8810343bfb58] fallback_alloc at ffffffff8115a55a torvalds#15 [ffff8810343bfbd8] ____cache_alloc_node at ffffffff8115a2d9 torvalds#16 [ffff8810343bfc38] kmem_cache_alloc at ffffffff8115b09b torvalds#17 [ffff8810343bfc78] sk_prot_alloc at ffffffff81411808 torvalds#18 [ffff8810343bfcb8] sk_alloc at ffffffff8141197c torvalds#19 [ffff8810343bfce8] inet_create at ffffffff81483ba6 torvalds#20 [ffff8810343bfd38] __sock_create at ffffffff8140b4a7 torvalds#21 [ffff8810343bfd98] xs_create_sock at ffffffffa01f649b [sunrpc] torvalds#22 [ffff8810343bfdd8] xs_tcp_setup_socket at ffffffffa01f6965 [sunrpc] torvalds#23 [ffff8810343bfe38] worker_thread at ffffffff810887d0 torvalds#24 [ffff8810343bfee8] kthread at ffffffff8108dd96 torvalds#25 [ffff8810343bff48] kernel_thread at ffffffff8100c1ca rpciod is trying to allocate memory for a new socket to talk to the server. The VM ends up calling ->releasepage to get more memory, and it tries to do a blocking commit. That commit can't succeed however without a connected socket, so we deadlock. Fix this by setting PF_FSTRANS on the workqueue task prior to doing the socket allocation, and having nfs_release_page check for that flag when deciding whether to do a commit call. Also, set PF_FSTRANS unconditionally in rpc_async_schedule since that function can also do allocations sometimes. Signed-off-by: Jeff Layton <[email protected]> Signed-off-by: Trond Myklebust <[email protected]> Signed-off-by: Ben Hutchings <[email protected]>

ERROR: do not initialise statics to 0 or NULL torvalds#24: FILE: scripts/pnmtologo.c:77: +static int is_plain_pbm = 0; WARNING: line over 80 characters torvalds#33: FILE: scripts/pnmtologo.c:108: + * between the digits. This is Ok cause we know a PBM can only have a '1' total: 1 errors, 1 warnings, 25 lines checked ./patches/scripts-pnmtologo-fix-for-plain-pbm.patch has style problems, please review. If any of these errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: Andreas Bießmann <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Signed-off-by: Andrew Morton <[email protected]>

WARNING: line over 80 characters torvalds#24: FILE: fs/binfmt_elf.c:1604: + info->psinfo.data = NULL; /* So we don't free this wrongly */ ERROR: code indent should use tabs where possible torvalds#26: FILE: fs/binfmt_elf.c:1606: + }$ WARNING: please, no spaces at the start of a line torvalds#26: FILE: fs/binfmt_elf.c:1606: + }$ total: 1 errors, 2 warnings, 11 lines checked NOTE: whitespace errors detected, you may wish to use scripts/cleanpatch or scripts/cleanfile ./patches/binfmt_elf-fix-corner-case-kfree-of-uninitialized-data.patch has style problems, please review. If any of these errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: Alan Cox <[email protected]> Signed-off-by: Andrew Morton <[email protected]>

…d reasons commit 5cf02d0 upstream. We've had some reports of a deadlock where rpciod ends up with a stack trace like this: PID: 2507 TASK: ffff88103691ab40 CPU: 14 COMMAND: "rpciod/14" #0 [ffff8810343bf2f0] schedule at ffffffff814dabd9 #1 [ffff8810343bf3b8] nfs_wait_bit_killable at ffffffffa038fc04 [nfs] #2 [ffff8810343bf3c8] __wait_on_bit at ffffffff814dbc2f #3 [ffff8810343bf418] out_of_line_wait_on_bit at ffffffff814dbcd8 #4 [ffff8810343bf488] nfs_commit_inode at ffffffffa039e0c1 [nfs] #5 [ffff8810343bf4f8] nfs_release_page at ffffffffa038bef6 [nfs] torvalds#6 [ffff8810343bf528] try_to_release_page at ffffffff8110c670 torvalds#7 [ffff8810343bf538] shrink_page_list.clone.0 at ffffffff81126271 torvalds#8 [ffff8810343bf668] shrink_inactive_list at ffffffff81126638 torvalds#9 [ffff8810343bf818] shrink_zone at ffffffff8112788f torvalds#10 [ffff8810343bf8c8] do_try_to_free_pages at ffffffff81127b1e torvalds#11 [ffff8810343bf958] try_to_free_pages at ffffffff8112812f torvalds#12 [ffff8810343bfa08] __alloc_pages_nodemask at ffffffff8111fdad torvalds#13 [ffff8810343bfb28] kmem_getpages at ffffffff81159942 torvalds#14 [ffff8810343bfb58] fallback_alloc at ffffffff8115a55a torvalds#15 [ffff8810343bfbd8] ____cache_alloc_node at ffffffff8115a2d9 torvalds#16 [ffff8810343bfc38] kmem_cache_alloc at ffffffff8115b09b torvalds#17 [ffff8810343bfc78] sk_prot_alloc at ffffffff81411808 torvalds#18 [ffff8810343bfcb8] sk_alloc at ffffffff8141197c torvalds#19 [ffff8810343bfce8] inet_create at ffffffff81483ba6 torvalds#20 [ffff8810343bfd38] __sock_create at ffffffff8140b4a7 torvalds#21 [ffff8810343bfd98] xs_create_sock at ffffffffa01f649b [sunrpc] torvalds#22 [ffff8810343bfdd8] xs_tcp_setup_socket at ffffffffa01f6965 [sunrpc] torvalds#23 [ffff8810343bfe38] worker_thread at ffffffff810887d0 torvalds#24 [ffff8810343bfee8] kthread at ffffffff8108dd96 torvalds#25 [ffff8810343bff48] kernel_thread at ffffffff8100c1ca rpciod is trying to allocate memory for a new socket to talk to the server. The VM ends up calling ->releasepage to get more memory, and it tries to do a blocking commit. That commit can't succeed however without a connected socket, so we deadlock. Fix this by setting PF_FSTRANS on the workqueue task prior to doing the socket allocation, and having nfs_release_page check for that flag when deciding whether to do a commit call. Also, set PF_FSTRANS unconditionally in rpc_async_schedule since that function can also do allocations sometimes. Signed-off-by: Jeff Layton <[email protected]> Signed-off-by: Trond Myklebust <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

ERROR: do not initialise statics to 0 or NULL #24: FILE: scripts/pnmtologo.c:77: +static int is_plain_pbm = 0; WARNING: line over 80 characters #33: FILE: scripts/pnmtologo.c:108: + * between the digits. This is Ok cause we know a PBM can only have a '1' total: 1 errors, 1 warnings, 25 lines checked ./patches/scripts-pnmtologo-fix-for-plain-pbm.patch has style problems, please review. If any of these errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: Andreas Bießmann <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Signed-off-by: Andrew Morton <[email protected]>

WARNING: line over 80 characters #24: FILE: fs/binfmt_elf.c:1604: + info->psinfo.data = NULL; /* So we don't free this wrongly */ ERROR: code indent should use tabs where possible #26: FILE: fs/binfmt_elf.c:1606: + }$ WARNING: please, no spaces at the start of a line #26: FILE: fs/binfmt_elf.c:1606: + }$ total: 1 errors, 2 warnings, 11 lines checked NOTE: whitespace errors detected, you may wish to use scripts/cleanpatch or scripts/cleanfile ./patches/binfmt_elf-fix-corner-case-kfree-of-uninitialized-data.patch has style problems, please review. If any of these errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: Alan Cox <[email protected]> Signed-off-by: Andrew Morton <[email protected]>

ERROR: do not initialise statics to 0 or NULL #24: FILE: scripts/pnmtologo.c:77: +static int is_plain_pbm = 0; WARNING: line over 80 characters #33: FILE: scripts/pnmtologo.c:108: + * between the digits. This is Ok cause we know a PBM can only have a '1' total: 1 errors, 1 warnings, 25 lines checked ./patches/scripts-pnmtologo-fix-for-plain-pbm.patch has style problems, please review. If any of these errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: Andreas Bießmann <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Signed-off-by: Andrew Morton <[email protected]>

Yan Burman reported following lockdep warning : ============================================= [ INFO: possible recursive locking detected ] 3.7.0+ #24 Not tainted --------------------------------------------- swapper/1/0 is trying to acquire lock: (&n->lock){++--..}, at: [<ffffffff8139f56e>] __neigh_event_send +0x2e/0x2f0 but task is already holding lock: (&n->lock){++--..}, at: [<ffffffff813f63f4>] arp_solicit+0x1d4/0x280 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&n->lock); lock(&n->lock); *** DEADLOCK *** May be due to missing lock nesting notation 4 locks held by swapper/1/0: #0: (((&n->timer))){+.-...}, at: [<ffffffff8104b350>] call_timer_fn+0x0/0x1c0 #1: (&n->lock){++--..}, at: [<ffffffff813f63f4>] arp_solicit +0x1d4/0x280 #2: (rcu_read_lock_bh){.+....}, at: [<ffffffff81395400>] dev_queue_xmit+0x0/0x5d0 #3: (rcu_read_lock_bh){.+....}, at: [<ffffffff813cb41e>] ip_finish_output+0x13e/0x640 stack backtrace: Pid: 0, comm: swapper/1 Not tainted 3.7.0+ #24 Call Trace: <IRQ> [<ffffffff8108c7ac>] validate_chain+0xdcc/0x11f0 [<ffffffff8108d570>] ? __lock_acquire+0x440/0xc30 [<ffffffff81120565>] ? kmem_cache_free+0xe5/0x1c0 [<ffffffff8108d570>] __lock_acquire+0x440/0xc30 [<ffffffff813c3570>] ? inet_getpeer+0x40/0x600 [<ffffffff8108d570>] ? __lock_acquire+0x440/0xc30 [<ffffffff8139f56e>] ? __neigh_event_send+0x2e/0x2f0 [<ffffffff8108ddf5>] lock_acquire+0x95/0x140 [<ffffffff8139f56e>] ? __neigh_event_send+0x2e/0x2f0 [<ffffffff8108d570>] ? __lock_acquire+0x440/0xc30 [<ffffffff81448d4b>] _raw_write_lock_bh+0x3b/0x50 [<ffffffff8139f56e>] ? __neigh_event_send+0x2e/0x2f0 [<ffffffff8139f56e>] __neigh_event_send+0x2e/0x2f0 [<ffffffff8139f99b>] neigh_resolve_output+0x16b/0x270 [<ffffffff813cb62d>] ip_finish_output+0x34d/0x640 [<ffffffff813cb41e>] ? ip_finish_output+0x13e/0x640 [<ffffffffa046f146>] ? vxlan_xmit+0x556/0xbec [vxlan] [<ffffffff813cb9a0>] ip_output+0x80/0xf0 [<ffffffff813ca368>] ip_local_out+0x28/0x80 [<ffffffffa046f25a>] vxlan_xmit+0x66a/0xbec [vxlan] [<ffffffffa046f146>] ? vxlan_xmit+0x556/0xbec [vxlan] [<ffffffff81394a50>] ? skb_gso_segment+0x2b0/0x2b0 [<ffffffff81449355>] ? _raw_spin_unlock_irqrestore+0x65/0x80 [<ffffffff81394c57>] ? dev_queue_xmit_nit+0x207/0x270 [<ffffffff813950c8>] dev_hard_start_xmit+0x298/0x5d0 [<ffffffff813956f3>] dev_queue_xmit+0x2f3/0x5d0 [<ffffffff81395400>] ? dev_hard_start_xmit+0x5d0/0x5d0 [<ffffffff813f5788>] arp_xmit+0x58/0x60 [<ffffffff813f59db>] arp_send+0x3b/0x40 [<ffffffff813f6424>] arp_solicit+0x204/0x280 [<ffffffff813a1a70>] ? neigh_add+0x310/0x310 [<ffffffff8139f515>] neigh_probe+0x45/0x70 [<ffffffff813a1c10>] neigh_timer_handler+0x1a0/0x2a0 [<ffffffff8104b3cf>] call_timer_fn+0x7f/0x1c0 [<ffffffff8104b350>] ? detach_if_pending+0x120/0x120 [<ffffffff8104b748>] run_timer_softirq+0x238/0x2b0 [<ffffffff813a1a70>] ? neigh_add+0x310/0x310 [<ffffffff81043e51>] __do_softirq+0x101/0x280 [<ffffffff814518cc>] call_softirq+0x1c/0x30 [<ffffffff81003b65>] do_softirq+0x85/0xc0 [<ffffffff81043a7e>] irq_exit+0x9e/0xc0 [<ffffffff810264f8>] smp_apic_timer_interrupt+0x68/0xa0 [<ffffffff8145122f>] apic_timer_interrupt+0x6f/0x80 <EOI> [<ffffffff8100a054>] ? mwait_idle+0xa4/0x1c0 [<ffffffff8100a04b>] ? mwait_idle+0x9b/0x1c0 [<ffffffff8100a6a9>] cpu_idle+0x89/0xe0 [<ffffffff81441127>] start_secondary+0x1b2/0x1b6 Bug is from arp_solicit(), releasing the neigh lock after arp_send() In case of vxlan, we eventually need to write lock a neigh lock later. Its a false positive, but we can get rid of it without lockdep annotations. We can instead use neigh_ha_snapshot() helper. Reported-by: Yan Burman <[email protected]> Signed-off-by: Eric Dumazet <[email protected]> Acked-by: Stephen Hemminger <[email protected]> Signed-off-by: David S. Miller <[email protected]>

Signed-off-by: Vineet Gupta <[email protected]>

ERROR: do not initialise statics to 0 or NULL torvalds#24: FILE: scripts/pnmtologo.c:77: +static int is_plain_pbm = 0; WARNING: line over 80 characters torvalds#33: FILE: scripts/pnmtologo.c:108: + * between the digits. This is Ok cause we know a PBM can only have a '1' total: 1 errors, 1 warnings, 25 lines checked ./patches/scripts-pnmtologo-fix-for-plain-pbm.patch has style problems, please review. If any of these errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: Andreas Bießmann <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Signed-off-by: Andrew Morton <[email protected]>

ERROR: do not initialise statics to 0 or NULL #24: FILE: scripts/pnmtologo.c:77: +static int is_plain_pbm = 0; WARNING: line over 80 characters #33: FILE: scripts/pnmtologo.c:108: + * between the digits. This is Ok cause we know a PBM can only have a '1' total: 1 errors, 1 warnings, 25 lines checked ./patches/scripts-pnmtologo-fix-for-plain-pbm.patch has style problems, please review. If any of these errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: Andreas Bießmann <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Signed-off-by: Andrew Morton <[email protected]>

ERROR: do not initialise statics to 0 or NULL torvalds#24: FILE: scripts/pnmtologo.c:77: +static int is_plain_pbm = 0; WARNING: line over 80 characters torvalds#33: FILE: scripts/pnmtologo.c:108: + * between the digits. This is Ok cause we know a PBM can only have a '1' total: 1 errors, 1 warnings, 25 lines checked ./patches/scripts-pnmtologo-fix-for-plain-pbm.patch has style problems, please review. If any of these errors are false positives, please report them to the maintainer, see CHECKPATCH in MAINTAINERS. Please run checkpatch prior to sending patches Cc: Andreas Bießmann <[email protected]> Cc: Geert Uytterhoeven <[email protected]> Signed-off-by: Andrew Morton <[email protected]>

…d reasons commit 5cf02d0 upstream. We've had some reports of a deadlock where rpciod ends up with a stack trace like this: PID: 2507 TASK: ffff88103691ab40 CPU: 14 COMMAND: "rpciod/14" #0 [ffff8810343bf2f0] schedule at ffffffff814dabd9 #1 [ffff8810343bf3b8] nfs_wait_bit_killable at ffffffffa038fc04 [nfs] #2 [ffff8810343bf3c8] __wait_on_bit at ffffffff814dbc2f #3 [ffff8810343bf418] out_of_line_wait_on_bit at ffffffff814dbcd8 #4 [ffff8810343bf488] nfs_commit_inode at ffffffffa039e0c1 [nfs] #5 [ffff8810343bf4f8] nfs_release_page at ffffffffa038bef6 [nfs] torvalds#6 [ffff8810343bf528] try_to_release_page at ffffffff8110c670 torvalds#7 [ffff8810343bf538] shrink_page_list.clone.0 at ffffffff81126271 torvalds#8 [ffff8810343bf668] shrink_inactive_list at ffffffff81126638 torvalds#9 [ffff8810343bf818] shrink_zone at ffffffff8112788f torvalds#10 [ffff8810343bf8c8] do_try_to_free_pages at ffffffff81127b1e torvalds#11 [ffff8810343bf958] try_to_free_pages at ffffffff8112812f torvalds#12 [ffff8810343bfa08] __alloc_pages_nodemask at ffffffff8111fdad torvalds#13 [ffff8810343bfb28] kmem_getpages at ffffffff81159942 torvalds#14 [ffff8810343bfb58] fallback_alloc at ffffffff8115a55a torvalds#15 [ffff8810343bfbd8] ____cache_alloc_node at ffffffff8115a2d9 torvalds#16 [ffff8810343bfc38] kmem_cache_alloc at ffffffff8115b09b torvalds#17 [ffff8810343bfc78] sk_prot_alloc at ffffffff81411808 torvalds#18 [ffff8810343bfcb8] sk_alloc at ffffffff8141197c torvalds#19 [ffff8810343bfce8] inet_create at ffffffff81483ba6 torvalds#20 [ffff8810343bfd38] __sock_create at ffffffff8140b4a7 torvalds#21 [ffff8810343bfd98] xs_create_sock at ffffffffa01f649b [sunrpc] torvalds#22 [ffff8810343bfdd8] xs_tcp_setup_socket at ffffffffa01f6965 [sunrpc] torvalds#23 [ffff8810343bfe38] worker_thread at ffffffff810887d0 torvalds#24 [ffff8810343bfee8] kthread at ffffffff8108dd96 torvalds#25 [ffff8810343bff48] kernel_thread at ffffffff8100c1ca rpciod is trying to allocate memory for a new socket to talk to the server. The VM ends up calling ->releasepage to get more memory, and it tries to do a blocking commit. That commit can't succeed however without a connected socket, so we deadlock. Fix this by setting PF_FSTRANS on the workqueue task prior to doing the socket allocation, and having nfs_release_page check for that flag when deciding whether to do a commit call. Also, set PF_FSTRANS unconditionally in rpc_async_schedule since that function can also do allocations sometimes. Signed-off-by: Jeff Layton <[email protected]> Signed-off-by: Trond Myklebust <[email protected]> Signed-off-by: Ben Hutchings <[email protected]>

@task

One of the problems that arise when converting dedicated custom threadpool to workqueue is that the shared worker pool used by workqueue anonimizes each worker making it more difficult to identify what the worker was doing on which target from the output of sysrq-t or debug dump from oops, BUG() and friends. For example, after writeback is converted to use workqueue instead of priviate thread pool, there's no easy to tell which backing device a writeback work item was working on at the time of task dump, which, according to our writeback brethren, is important in tracking down issues with a lot of mounted file systems on a lot of different devices. This patchset implements a way for a work function to mark its execution instance so that task dump of the worker task includes information to indicate what the work item was doing. An example WARN dump would look like the following. WARNING: at fs/fs-writeback.c:1015 bdi_writeback_workfn+0x2b4/0x3c0() Modules linked in: CPU: 0 Pid: 28 Comm: kworker/u18:0 Not tainted 3.9.0-rc1-work+ torvalds#24 Hardware name: empty empty/S3992, BIOS 080011 10/26/2007 Workqueue: writeback bdi_writeback_workfn (flush-8:16) ffffffff820a3a98 ffff88015b927cb8 ffffffff81c61855 ffff88015b927cf8 ffffffff8108f500 0000000000000000 ffff88007a171948 ffff88007a1716b0 ffff88015b49df00 ffff88015b8d3940 0000000000000000 ffff88015b927d08 Call Trace: [<ffffffff81c61855>] dump_stack+0x19/0x1b [<ffffffff8108f500>] warn_slowpath_common+0x70/0xa0 ... This patch: Implement probe_kthread_data() which returns kthread_data if accessible. The function is equivalent to kthread_data() except that the specified @task may not be a kthread or its vfork_done is already cleared rendering struct kthread inaccessible. In the former case, probe_kthread_data() may return any value. In the latter, NULL. This will be used to safely print debug information without affecting synchronization in the normal paths. Workqueue debug info printing on dump_stack() and friends will make use of it. Signed-off-by: Tejun Heo <[email protected]> Cc: Oleg Nesterov <[email protected]> Acked-by: Jan Kara <[email protected]> Cc: Dave Chinner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Jens Axboe <[email protected]> Cc: Peter Zijlstra <[email protected]> Signed-off-by: Andrew Morton <[email protected]>

Writeback has been recently converted to use workqueue instead of its private thread pool implementation. One negative side effect of this conversion is that there's no easy to tell which backing device a writeback work item was working on at the time of task dump, be it sysrq-t, BUG, WARN or whatever, which, according to our writeback brethren, is important in tracking down issues with a lot of mounted file systems on a lot of different devices. This patch restores that information using the new worker description facility. bdi_writeback_workfn() calls set_work_desc() to identify which bdi it's working on. The description is printed out together with the worqueue name and worker function as in the following example dump. WARNING: at fs/fs-writeback.c:1015 bdi_writeback_workfn+0x2b4/0x3c0() Modules linked in: Pid: 28, comm: kworker/u18:0 Not tainted 3.9.0-rc1-work+ torvalds#24 empty empty/S3992 Workqueue: writeback bdi_writeback_workfn (flush-8:16) ffffffff820a3a98 ffff88015b927cb8 ffffffff81c61855 ffff88015b927cf8 ffffffff8108f500 0000000000000000 ffff88007a171948 ffff88007a1716b0 ffff88015b49df00 ffff88015b8d3940 0000000000000000 ffff88015b927d08 Call Trace: [<ffffffff81c61855>] dump_stack+0x19/0x1b [<ffffffff8108f500>] warn_slowpath_common+0x70/0xa0 [<ffffffff8108f54a>] warn_slowpath_null+0x1a/0x20 [<ffffffff81200144>] bdi_writeback_workfn+0x2b4/0x3c0 [<ffffffff810b4c87>] process_one_work+0x1d7/0x660 [<ffffffff810b5c72>] worker_thread+0x122/0x380 [<ffffffff810bdfea>] kthread+0xea/0xf0 [<ffffffff81c6cedc>] ret_from_fork+0x7c/0xb0 Signed-off-by: Tejun Heo <[email protected]> Cc: Dave Chinner <[email protected]> Cc: Jan Kara <[email protected]> Cc: Jens Axboe <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Peter Zijlstra <[email protected]> Signed-off-by: Andrew Morton <[email protected]>

@strlen

Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: NipaLocal <nipa@local>

@strlen

Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: NipaLocal <nipa@local>

@strlen

Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: NipaLocal <nipa@local>

@strlen

Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: NipaLocal <nipa@local>

@strlen

Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: NipaLocal <nipa@local>

@strlen

Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: NipaLocal <nipa@local>

@strlen

Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: NipaLocal <nipa@local>

@strlen

Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: NipaLocal <nipa@local>

@strlen

Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: NipaLocal <nipa@local>

@strlen

Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]>

commit 4a058b3 upstream. KASAN reported a null-ptr-deref issue when executing the following command: # echo ts2020 0x20 > /sys/bus/i2c/devices/i2c-0/new_device KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 53 UID: 0 PID: 970 Comm: systemd-udevd Not tainted 6.12.0-rc2+ torvalds#24 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009) RIP: 0010:ts2020_probe+0xad/0xe10 [ts2020] RSP: 0018:ffffc9000abbf598 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffffc0714809 RDX: 0000000000000002 RSI: ffff88811550be00 RDI: 0000000000000010 RBP: ffff888109868800 R08: 0000000000000001 R09: fffff52001577eb6 R10: 0000000000000000 R11: ffffc9000abbff50 R12: ffffffffc0714790 R13: 1ffff92001577eb8 R14: ffffffffc07190d0 R15: 0000000000000001 FS: 00007f95f13b98c0(0000) GS:ffff888149280000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555d2634b000 CR3: 0000000152236000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ts2020_probe+0xad/0xe10 [ts2020] i2c_device_probe+0x421/0xb40 really_probe+0x266/0x850 ... The cause of the problem is that when using sysfs to dynamically register an i2c device, there is no platform data, but the probe process of ts2020 needs to use platform data, resulting in a null pointer being accessed. Solve this problem by adding checks to platform data. Fixes: dc245a5 ("[media] ts2020: implement I2C client bindings") Cc: <[email protected]> Signed-off-by: Li Zetao <[email protected]> Signed-off-by: Hans Verkuil <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

there is a global spinlock between reset and clk, if locked in reset, then print some debug information, maybe dead-lock when uart driver try to disable clk. Backtrace stopped: frame did not save the PC (gdb) thread 4 [Switching to thread 4 (Thread 4)] #0 cpu_relax () at ./arch/riscv/include/asm/vdso/processor.h:22 22 ./arch/riscv/include/asm/vdso/processor.h: No such file or directory. (gdb) bt #0 cpu_relax () at ./arch/riscv/include/asm/vdso/processor.h:22 #1 arch_spin_lock (lock=lock@entry=0xffffffff81a57cd0 <enable_lock>) at ./include/asm-generic/spinlock.h:49 #2 do_raw_spin_lock (lock=lock@entry=0xffffffff81a57cd0 <enable_lock>) at ./include/linux/spinlock.h:186 #3 0xffffffff80aa21ce in __raw_spin_lock_irqsave (lock=0xffffffff81a57cd0 <enable_lock>) at ./include/linux/spinlock_api_smp.h:111 #4 _raw_spin_lock_irqsave (lock=lock@entry=0xffffffff81a57cd0 <enable_lock>) at kernel/locking/spinlock.c:162 #5 0xffffffff80563416 in clk_enable_lock () at ./include/linux/spinlock.h:325 torvalds#6 0xffffffff805648de in clk_core_disable_lock (core=0xffffffd900512500) at drivers/clk/clk.c:1062 torvalds#7 0xffffffff8056527e in clk_disable (clk=<optimized out>) at drivers/clk/clk.c:1084 torvalds#8 clk_disable (clk=0xffffffd9048b5100) at drivers/clk/clk.c:1079 torvalds#9 0xffffffff8059e5d4 in serial_pxa_console_write (co=<optimized out>, s=0xffffffff81a68250 <text> "[ 14.708612] [RESET][spacemit_reset_set][373]:assert = 1, id = 59 \n", count=<optimized out>) at drivers/tty/serial/pxa_k1x.c:1724 torvalds#10 0xffffffff8004a34c in call_console_driver (dropped_text=0xffffffff81a68650 <dropped_text> "", len=69, text=0xffffffff81a68250 <text> "[ 14.708612] [RESET][spacemit_reset_set][373]:assert = 1, id = 59 \n", con=0xffffffff81964c10 <serial_pxa_console>) at kernel/printk/printk.c:1942 torvalds#11 console_emit_next_record (con=con@entry=0xffffffff81964c10 <serial_pxa_console>, ext_text=<optimized out>, dropped_text=0xffffffff81a68650 <dropped_text> "", handover=0xffffffc80578baa7, text=0xffffffff81a68250 <text> "[ 14.708612] [RESET][spacemit_reset_set][373]:assert = 1, id = 59 \n") at kernel/printk/printk.c:2731 torvalds#12 0xffffffff8004a49a in console_flush_all (handover=0xffffffc80578baa7, next_seq=<synthetic pointer>, do_cond_resched=false) at kernel/printk/printk.c:2793 torvalds#13 console_unlock () at kernel/printk/printk.c:2860 torvalds#14 0xffffffff8004b388 in vprintk_emit (facility=facility@entry=0, level=<optimized out>, level@entry=-1, dev_info=dev_info@entry=0x0, fmt=<optimized out>, args=<optimized out>) at kernel/printk/printk.c:2268 torvalds#15 0xffffffff8004b3ae in vprintk_default (fmt=<optimized out>, args=<optimized out>) at kernel/printk/printk.c:2279 torvalds#16 0xffffffff8004b646 in vprintk (fmt=fmt@entry=0xffffffff813be470 "\001\066[RESET][%s][%d]:assert = %d, id = %d \n", args=args@entry=0xffffffc80578bbd8) at kernel/printk/printk_safe.c:50 torvalds#17 0xffffffff80a880d6 in _printk (fmt=fmt@entry=0xffffffff813be470 "\001\066[RESET][%s][%d]:assert = %d, id = %d \n") at kernel/printk/printk.c:2289 torvalds#18 0xffffffff80a90bb6 in spacemit_reset_set (rcdev=rcdev@entry=0xffffffff81f563a8 <k1x_reset_controller+8>, id=id@entry=59, assert=assert@entry=true) at drivers/reset/reset-spacemit-k1x.c:373 torvalds#19 0xffffffff805823b6 in spacemit_reset_update (assert=true, id=59, rcdev=0xffffffff81f563a8 <k1x_reset_controller+8>) at drivers/reset/reset-spacemit-k1x.c:401 torvalds#20 spacemit_reset_update (assert=true, id=59, rcdev=0xffffffff81f563a8 <k1x_reset_controller+8>) at drivers/reset/reset-spacemit-k1x.c:387 torvalds#21 spacemit_reset_assert (rcdev=0xffffffff81f563a8 <k1x_reset_controller+8>, id=59) at drivers/reset/reset-spacemit-k1x.c:413 torvalds#22 0xffffffff8058158e in reset_control_assert (rstc=0xffffffd902b2f280) at drivers/reset/core.c:485 torvalds#23 0xffffffff807ccf96 in cpp_disable_clocks (cpp_dev=cpp_dev@entry=0xffffffd904cc9040) at drivers/media/platform/spacemit/camera/cam_cpp/k1x_cpp.c:960 torvalds#24 0xffffffff807cd0b2 in cpp_release_hardware (cpp_dev=cpp_dev@entry=0xffffffd904cc9040) at drivers/media/platform/spacemit/camera/cam_cpp/k1x_cpp.c:1038 torvalds#25 0xffffffff807cd990 in cpp_close_node (sd=<optimized out>, fh=<optimized out>) at drivers/media/platform/spacemit/camera/cam_cpp/k1x_cpp.c:1135 torvalds#26 0xffffffff8079525e in subdev_close (file=0xffffffd906645d00) at drivers/media/v4l2-core/v4l2-subdev.c:105 torvalds#27 0xffffffff8078e49e in v4l2_release (inode=<optimized out>, filp=0xffffffd906645d00) at drivers/media/v4l2-core/v4l2-dev.c:459 torvalds#28 0xffffffff80154974 in __fput (file=0xffffffd906645d00) at fs/file_table.c:320 torvalds#29 0xffffffff80154aa2 in ____fput (work=<optimized out>) at fs/file_table.c:348 torvalds#30 0xffffffff8002677e in task_work_run () at kernel/task_work.c:179 torvalds#31 0xffffffff800053b4 in resume_user_mode_work (regs=0xffffffc80578bee0) at ./include/linux/resume_user_mode.h:49 torvalds#32 do_work_pending (regs=0xffffffc80578bee0, thread_info_flags=<optimized out>) at arch/riscv/kernel/signal.c:478 torvalds#33 0xffffffff800039c6 in handle_exception () at arch/riscv/kernel/entry.S:374 Backtrace stopped: frame did not save the PC (gdb) thread 1 [Switching to thread 1 (Thread 1)] #0 0xffffffff80047e9c in arch_spin_lock (lock=lock@entry=0xffffffff81a57cd8 <g_cru_lock>) at ./include/asm-generic/spinlock.h:49 49 ./include/asm-generic/spinlock.h: No such file or directory. (gdb) bt #0 0xffffffff80047e9c in arch_spin_lock (lock=lock@entry=0xffffffff81a57cd8 <g_cru_lock>) at ./include/asm-generic/spinlock.h:49 #1 do_raw_spin_lock (lock=lock@entry=0xffffffff81a57cd8 <g_cru_lock>) at ./include/linux/spinlock.h:186 #2 0xffffffff80aa21ce in __raw_spin_lock_irqsave (lock=0xffffffff81a57cd8 <g_cru_lock>) at ./include/linux/spinlock_api_smp.h:111 #3 _raw_spin_lock_irqsave (lock=0xffffffff81a57cd8 <g_cru_lock>) at kernel/locking/spinlock.c:162 #4 0xffffffff8056c4cc in ccu_mix_disable (hw=0xffffffff81956858 <sdh2_clk+120>) at ./include/linux/spinlock.h:325 #5 0xffffffff80564832 in clk_core_disable (core=0xffffffd900529900) at drivers/clk/clk.c:1051 torvalds#6 clk_core_disable (core=0xffffffd900529900) at drivers/clk/clk.c:1031 torvalds#7 0xffffffff805648e6 in clk_core_disable_lock (core=0xffffffd900529900) at drivers/clk/clk.c:1063 torvalds#8 0xffffffff8056527e in clk_disable (clk=<optimized out>) at drivers/clk/clk.c:1084 torvalds#9 clk_disable (clk=clk@entry=0xffffffd904fafa80) at drivers/clk/clk.c:1079 torvalds#10 0xffffffff808bb898 in clk_disable_unprepare (clk=0xffffffd904fafa80) at ./include/linux/clk.h:1085 torvalds#11 0xffffffff808bb916 in spacemit_sdhci_runtime_suspend (dev=<optimized out>) at drivers/mmc/host/sdhci-of-k1x.c:1469 torvalds#12 0xffffffff8066e8e2 in pm_generic_runtime_suspend (dev=<optimized out>) at drivers/base/power/generic_ops.c:25 torvalds#13 0xffffffff80670398 in __rpm_callback (cb=cb@entry=0xffffffff8066e8ca <pm_generic_runtime_suspend>, dev=dev@entry=0xffffffd9018a2810) at drivers/base/power/runtime.c:395 torvalds#14 0xffffffff806704b8 in rpm_callback (cb=cb@entry=0xffffffff8066e8ca <pm_generic_runtime_suspend>, dev=dev@entry=0xffffffd9018a2810) at drivers/base/power/runtime.c:529 torvalds#15 0xffffffff80670bdc in rpm_suspend (dev=0xffffffd9018a2810, rpmflags=<optimized out>) at drivers/base/power/runtime.c:672 torvalds#16 0xffffffff806716de in pm_runtime_work (work=0xffffffd9018a2948) at drivers/base/power/runtime.c:974 torvalds#17 0xffffffff800236f4 in process_one_work (worker=worker@entry=0xffffffd9013ee9c0, work=0xffffffd9018a2948) at kernel/workqueue.c:2289 torvalds#18 0xffffffff80023ba6 in worker_thread (__worker=0xffffffd9013ee9c0) at kernel/workqueue.c:2436 torvalds#19 0xffffffff80028bb2 in kthread (_create=0xffffffd9017de840) at kernel/kthread.c:376 torvalds#20 0xffffffff80003934 in handle_exception () at arch/riscv/kernel/entry.S:249 Backtrace stopped: frame did not save the PC (gdb) Change-Id: Ia95b41ffd6c1893c9c5e9c1c9fc0c155ea902d2c

commit 4a058b3 upstream. KASAN reported a null-ptr-deref issue when executing the following command: # echo ts2020 0x20 > /sys/bus/i2c/devices/i2c-0/new_device KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 53 UID: 0 PID: 970 Comm: systemd-udevd Not tainted 6.12.0-rc2+ torvalds#24 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009) RIP: 0010:ts2020_probe+0xad/0xe10 [ts2020] RSP: 0018:ffffc9000abbf598 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffffc0714809 RDX: 0000000000000002 RSI: ffff88811550be00 RDI: 0000000000000010 RBP: ffff888109868800 R08: 0000000000000001 R09: fffff52001577eb6 R10: 0000000000000000 R11: ffffc9000abbff50 R12: ffffffffc0714790 R13: 1ffff92001577eb8 R14: ffffffffc07190d0 R15: 0000000000000001 FS: 00007f95f13b98c0(0000) GS:ffff888149280000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555d2634b000 CR3: 0000000152236000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ts2020_probe+0xad/0xe10 [ts2020] i2c_device_probe+0x421/0xb40 really_probe+0x266/0x850 ... The cause of the problem is that when using sysfs to dynamically register an i2c device, there is no platform data, but the probe process of ts2020 needs to use platform data, resulting in a null pointer being accessed. Solve this problem by adding checks to platform data. Fixes: dc245a5 ("[media] ts2020: implement I2C client bindings") Cc: <[email protected]> Signed-off-by: Li Zetao <[email protected]> Signed-off-by: Hans Verkuil <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

@strlen

[ Upstream commit 146b6f1 ] Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

@strlen

[ Upstream commit 146b6f1 ] Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

commit 4a058b3 upstream. KASAN reported a null-ptr-deref issue when executing the following command: # echo ts2020 0x20 > /sys/bus/i2c/devices/i2c-0/new_device KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 53 UID: 0 PID: 970 Comm: systemd-udevd Not tainted 6.12.0-rc2+ torvalds#24 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009) RIP: 0010:ts2020_probe+0xad/0xe10 [ts2020] RSP: 0018:ffffc9000abbf598 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffffc0714809 RDX: 0000000000000002 RSI: ffff88811550be00 RDI: 0000000000000010 RBP: ffff888109868800 R08: 0000000000000001 R09: fffff52001577eb6 R10: 0000000000000000 R11: ffffc9000abbff50 R12: ffffffffc0714790 R13: 1ffff92001577eb8 R14: ffffffffc07190d0 R15: 0000000000000001 FS: 00007f95f13b98c0(0000) GS:ffff888149280000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555d2634b000 CR3: 0000000152236000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ts2020_probe+0xad/0xe10 [ts2020] i2c_device_probe+0x421/0xb40 really_probe+0x266/0x850 ... The cause of the problem is that when using sysfs to dynamically register an i2c device, there is no platform data, but the probe process of ts2020 needs to use platform data, resulting in a null pointer being accessed. Solve this problem by adding checks to platform data. Fixes: dc245a5 ("[media] ts2020: implement I2C client bindings") Cc: <[email protected]> Signed-off-by: Li Zetao <[email protected]> Signed-off-by: Hans Verkuil <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

@strlen

[ Upstream commit 146b6f1 ] Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

@strlen

[ Upstream commit 146b6f1 ] Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

@strlen

[ Upstream commit 146b6f1 ] Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

commit 4a058b3 upstream. KASAN reported a null-ptr-deref issue when executing the following command: # echo ts2020 0x20 > /sys/bus/i2c/devices/i2c-0/new_device KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 53 UID: 0 PID: 970 Comm: systemd-udevd Not tainted 6.12.0-rc2+ torvalds#24 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009) RIP: 0010:ts2020_probe+0xad/0xe10 [ts2020] RSP: 0018:ffffc9000abbf598 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffffc0714809 RDX: 0000000000000002 RSI: ffff88811550be00 RDI: 0000000000000010 RBP: ffff888109868800 R08: 0000000000000001 R09: fffff52001577eb6 R10: 0000000000000000 R11: ffffc9000abbff50 R12: ffffffffc0714790 R13: 1ffff92001577eb8 R14: ffffffffc07190d0 R15: 0000000000000001 FS: 00007f95f13b98c0(0000) GS:ffff888149280000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555d2634b000 CR3: 0000000152236000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ts2020_probe+0xad/0xe10 [ts2020] i2c_device_probe+0x421/0xb40 really_probe+0x266/0x850 ... The cause of the problem is that when using sysfs to dynamically register an i2c device, there is no platform data, but the probe process of ts2020 needs to use platform data, resulting in a null pointer being accessed. Solve this problem by adding checks to platform data. Fixes: dc245a5 ("[media] ts2020: implement I2C client bindings") Cc: <[email protected]> Signed-off-by: Li Zetao <[email protected]> Signed-off-by: Hans Verkuil <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

@strlen

[ Upstream commit 146b6f1 ] Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

@strlen

[ Upstream commit 146b6f1 ] Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

@strlen

[ Upstream commit 146b6f1 ] Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

commit 4a058b3 upstream. KASAN reported a null-ptr-deref issue when executing the following command: # echo ts2020 0x20 > /sys/bus/i2c/devices/i2c-0/new_device KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 53 UID: 0 PID: 970 Comm: systemd-udevd Not tainted 6.12.0-rc2+ torvalds#24 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009) RIP: 0010:ts2020_probe+0xad/0xe10 [ts2020] RSP: 0018:ffffc9000abbf598 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffffc0714809 RDX: 0000000000000002 RSI: ffff88811550be00 RDI: 0000000000000010 RBP: ffff888109868800 R08: 0000000000000001 R09: fffff52001577eb6 R10: 0000000000000000 R11: ffffc9000abbff50 R12: ffffffffc0714790 R13: 1ffff92001577eb8 R14: ffffffffc07190d0 R15: 0000000000000001 FS: 00007f95f13b98c0(0000) GS:ffff888149280000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555d2634b000 CR3: 0000000152236000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ts2020_probe+0xad/0xe10 [ts2020] i2c_device_probe+0x421/0xb40 really_probe+0x266/0x850 ... The cause of the problem is that when using sysfs to dynamically register an i2c device, there is no platform data, but the probe process of ts2020 needs to use platform data, resulting in a null pointer being accessed. Solve this problem by adding checks to platform data. Fixes: dc245a5 ("[media] ts2020: implement I2C client bindings") Cc: <[email protected]> Signed-off-by: Li Zetao <[email protected]> Signed-off-by: Hans Verkuil <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

@strlen

[ Upstream commit 146b6f1 ] Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

@strlen

[ Upstream commit 146b6f1 ] Under certain kernel configurations when building with Clang/LLVM, the compiler does not generate a return or jump as the terminator instruction for ip_vs_protocol_init(), triggering the following objtool warning during build time: vmlinux.o: warning: objtool: ip_vs_protocol_init() falls through to next function __initstub__kmod_ip_vs_rr__935_123_ip_vs_rr_init6() At runtime, this either causes an oops when trying to load the ipvs module or a boot-time panic if ipvs is built-in. This same issue has been reported by the Intel kernel test robot previously. Digging deeper into both LLVM and the kernel code reveals this to be a undefined behavior problem. ip_vs_protocol_init() uses a on-stack buffer of 64 chars to store the registered protocol names and leaves it uninitialized after definition. The function calls strnlen() when concatenating protocol names into the buffer. With CONFIG_FORTIFY_SOURCE strnlen() performs an extra step to check whether the last byte of the input char buffer is a null character (commit 3009f89 ("fortify: Allow strlen() and strnlen() to pass compile-time known lengths")). This, together with possibly other configurations, cause the following IR to be generated: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #5 section ".init.text" align 16 !kcfi_type !29 { %1 = alloca [64 x i8], align 16 ... 14: ; preds = %11 %15 = getelementptr inbounds i8, ptr %1, i64 63 %16 = load i8, ptr %15, align 1 %17 = tail call i1 @llvm.is.constant.i8(i8 %16) %18 = icmp eq i8 %16, 0 %19 = select i1 %17, i1 %18, i1 false br i1 %19, label %20, label %23 20: ; preds = %14 %21 = call i64 @strlen(ptr noundef nonnull dereferenceable(1) %1) torvalds#23 ... 23: ; preds = %14, %11, %20 %24 = call i64 @strnlen(ptr noundef nonnull dereferenceable(1) %1, i64 noundef 64) torvalds#24 ... } The above code calculates the address of the last char in the buffer (value %15) and then loads from it (value %16). Because the buffer is never initialized, the LLVM GVN pass marks value %16 as undefined: %13 = getelementptr inbounds i8, ptr %1, i64 63 br i1 undef, label %14, label %17 This gives later passes (SCCP, in particular) more DCE opportunities by propagating the undef value further, and eventually removes everything after the load on the uninitialized stack location: define hidden i32 @ip_vs_protocol_init() local_unnamed_addr #0 section ".init.text" align 16 !kcfi_type !11 { %1 = alloca [64 x i8], align 16 ... 12: ; preds = %11 %13 = getelementptr inbounds i8, ptr %1, i64 63 unreachable } In this way, the generated native code will just fall through to the next function, as LLVM does not generate any code for the unreachable IR instruction and leaves the function without a terminator. Zero the on-stack buffer to avoid this possible UB. Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: kernel test robot <[email protected]> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ Co-developed-by: Ruowen Qin <[email protected]> Signed-off-by: Ruowen Qin <[email protected]> Signed-off-by: Jinghao Jia <[email protected]> Acked-by: Julian Anastasov <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: Sasha Levin <[email protected]>

Update drivers/staging/bcm/InterfaceInit.h

94e6860

Added device ID of ZTE AX326.

vineetgarc referenced this pull request in foss-for-synopsys-dwc-arc-processors/linux Oct 31, 2012

ARC: SMP resurrect #24: Makefile fix for relo errors

805b0d4

Signed-off-by: Vineet Gupta <[email protected]>

vineetgarc referenced this pull request in foss-for-synopsys-dwc-arc-processors/linux Dec 31, 2012

ARC: SMP resurrect #24: Makefile fix for relo errors

a68d78f

Signed-off-by: Vineet Gupta <[email protected]>

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Update drivers/staging/bcm/InterfaceInit.h #24

Update drivers/staging/bcm/InterfaceInit.h #24

mdminhazulhaque commented Oct 23, 2012

asamy commented Nov 3, 2012

Update drivers/staging/bcm/InterfaceInit.h #24

Update drivers/staging/bcm/InterfaceInit.h #24

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mdminhazulhaque commented Oct 23, 2012

asamy commented Nov 3, 2012