Make failing to compile kvdo & uds modules on Debian

[albertdipp]

Hi There,

I am trying to compile the kvdo and uds modules on Debian 11.2 running kernel "5.10.0-12-amd64"

I haven't updated in a wee while and now it seems that I can't compile the modules anymore under the latest Debian version.

Steps to reproduce:

1. Fully up to date - fresh Debian install
2. Install all pre-reqs like linux-headers, make etc...
3. After a git clone, under the kvdo directory run "make -C /usr/src/linux-headers-uname -r M=pwd" I get the following error:
   CC [M] /root/modules/vdo/kvdo/vdo/allocatingVIO.o
   CC [M] /root/modules/vdo/kvdo/vdo/allocationSelector.o
   CC [M] /root/modules/vdo/kvdo/vdo/batchProcessor.o
   CC [M] /root/modules/vdo/kvdo/vdo/bio.o
   /root/modules/vdo/kvdo/vdo/bio.c: In function ‘vdo_bio_copy_data_in’:
   /root/modules/vdo/kvdo/vdo/bio.c:45:3: error: implicit declaration of function ‘memcpy_from_bvec’; did you mean ‘memcpy_fromio’? [-Werror=implicit-function-declaration]
   45 | memcpy_from_bvec(data_ptr, &biovec);
   | ^~~~~~~~~~~~~~~~
   | memcpy_fromio
   /root/modules/vdo/kvdo/vdo/bio.c: In function ‘vdo_bio_copy_data_out’:
   /root/modules/vdo/kvdo/vdo/bio.c:57:3: error: implicit declaration of function ‘memcpy_to_bvec’; did you mean ‘memcpy_toio’? [-Werror=implicit-function-declaration]
   57 | memcpy_to_bvec(&biovec, data_ptr);
   | ^~~~~~~~~~~~~~
   | memcpy_toio
   cc1: all warnings being treated as errors
   make[3]: *** [/usr/src/linux-headers-5.10.0-12-common/scripts/Makefile.build:285: /root/modules/vdo/kvdo/vdo/bio.o] Error 1
   make[2]: *** [/usr/src/linux-headers-5.10.0-12-common/scripts/Makefile.build:502: /root/modules/vdo/kvdo/vdo] Error 2
   make[1]: *** [/usr/src/linux-headers-5.10.0-12-common/Makefile:1846: /root/modules/vdo/kvdo] Error 2
   make: *** [/usr/src/linux-headers-5.10.0-12-common/Makefile:185: __sub-make] Error 2
   make: Leaving directory '/usr/src/linux-headers-5.10.0-12-amd64'
   [root@hawea]~/modules/vdo/kvdo

Not sure if I am doing something wrong? I followed my notes and history to retrace my steps but never recalled bumping my head in to this issue on an earlier version of Debian.

[sweettea]

Good morning!

Which VDO version/branch of the repository are you trying to compile?

[albertdipp]

Good Morning :) if it still is morning for you :)

I was cloning master [Version 8.1.1.371]

[albertdipp]

Some more testing later, seems that the issue was brought in with version 8.1.1.360.

Versions including 8.1.1.287 and earlier compile just fine.

edit: wrong version :)

[sweettea]

Ah, you're right. Specifically, if you search for "// XXX workaround for LINUX_VERSION_CODE < KERNEL_VERSION(5,15,0)" in 819203a, you'll see the code that was taken out which had a conditional for older kernels.

@corwin, which major/minor version is most suitable for a 5.10 kernel?

[lorelei-sakai]

I tried to respond to this yesterday, but apparently I haven't figured out the right technique for replying by mail.

I think there are really only a few options. Either stick with the 8.1.1.287 release, or restore the workaround Sweet Tea mentioned. The code in that workaround should still work. But I believe no version under active development will work with a 5.10 kernel.

We don't test with a 5.10 kernel much and I guess we got overzealous about removing support for it. As the comment indicates, the 8.1.x versions are aimed at 5.15+ kernels, while older versions expect older (4.18+) kernels that will likely have different compilation problems.

I'll look into possibly restoring that support in a future version.

[tigerblue77]

Hello there,

I encounter exactly the same error : memcpy_to_bvec() is missing on vdo/bio.c file.
I'm using Debian 11.3 with 5.10.0-13 kernel. It's stable Debian's branch so it could be a great idea to recover support 🥺 I want to use VDO on my almost-production environnent 😄

Don't hesitate to tell me if I can help.

[tigerblue77]

restore the workaround Sweet Tea mentioned

Done, tested locally and create a PR and now it compiles well !!! 😁

Edit : Don't hesitate to check my installation script and improve it by following this link ! 😉

[lorelei-sakai]

[removed duplicate comment] I'm not sure why this comment got reposted; I did not intend to do that.