Re: kbuild: add support for zstd compressed modules

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi.

On Thu, Apr 08, 2021 at 09:04:11PM +0200, Sedat Dilek wrote:
> I tried this patch together with my build-script which uses builddeb
> to generate Debian packages.
> 
> Currently, I test a setup with Clang-LTO + DWARF-v5 (and BTF).
> 
> With this patch I get total strange numbers.
> 
> The Kconfig changes to my previous kernel of today:
> 
> $ scripts/diffconfig /boot/config-5.12.0-rc6-3-amd64-clang12-lto
> /boot/config-5.12.0-rc6-4-amd64-clang12-lto
> BUILD_SALT "5.12.0-rc6-3-amd64-clang12-lto" -> "5.12.0-rc6-4-amd64-clang12-lto"
> MODULE_COMPRESS_NONE y -> n
> MODULE_COMPRESS_ZSTD n -> y
> 
> The generated linux-image Debian package is greater in size than the
> linux-image DEBUG package.
> Normally, this is vice-versa.
> 
> With:
> 
> $ du -s -m linux-image-5.12.0-rc6-4-amd64-clang12-lto*
> 969     linux-image-5.12.0-rc6-4-amd64-clang12-lto_5.12.0~rc6-4~bullseye+dileks1_amd64.deb
> 97      linux-image-5.12.0-rc6-4-amd64-clang12-lto-dbg_5.12.0~rc6-4~bullseye+dileks1_amd64.deb
> (DEBUG)
> 
> Without:
> 
> $ du -s -m linux-image-5.12.0-rc6-3-amd64-clang12-lto*
> 60      linux-image-5.12.0-rc6-3-amd64-clang12-lto_5.12.0~rc6-3~bullseye+dileks1_amd64.deb
> 599     linux-image-5.12.0-rc6-3-amd64-clang12-lto-dbg_5.12.0~rc6-3~bullseye+dileks1_amd64.deb
> (DEBUG)
> 
> The kernel-modules directory numbers:
> 
> With:
> 
> # du -s -m /lib/modules/5.12.0-rc6-4-amd64-clang12-lto/
> 999     /lib/modules/5.12.0-rc6-4-amd64-clang12-lto/
> 
> Without:
> 
> # du -s -m /lib/modules/5.12.0-rc6-3-amd64-clang12-lto/
> 354     /lib/modules/5.12.0-rc6-3-amd64-clang12-lto/
> 
> Checking iwlwifi kernel-module:
> 
> With:
> 
> # find /lib/modules/5.12.0-rc6-4-amd64-clang12-lto/ -name
> 'iwlwifi.ko*' -type f -print | xargs ls -l
> -rw-r--r-- 1 root root 2381066  8. Apr 15:47
> /lib/modules/5.12.0-rc6-4-amd64-clang12-lto/kernel/drivers/net/wireless/intel/iwlwifi/iwlwifi.ko.zst
> 
> # find /lib/modules/5.12.0-rc6-4-amd64-clang12-lto/ -name
> 'iwlwifi.ko*' -type f -print | xargs du -k
> 2328    /lib/modules/5.12.0-rc6-4-amd64-clang12-lto/kernel/drivers/net/wireless/intel/iwlwifi/iwlwifi.ko.zst
> 
> Without:
> 
> # find /lib/modules/5.12.0-rc6-3-amd64-clang12-lto/ -name
> 'iwlwifi.ko*' -type f -print | xargs ls -l
> -rw-r--r-- 1 root root 675976  8. Apr 09:35
> /lib/modules/5.12.0-rc6-3-amd64-clang12-lto/kernel/drivers/net/wireless/intel/iwlwifi/iwlwifi.ko
> 
> # find /lib/modules/5.12.0-rc6-3-amd64-clang12-lto/ -name
> 'iwlwifi.ko*' -type f -print | xargs du -k
> 664     /lib/modules/5.12.0-rc6-3-amd64-clang12-lto/kernel/drivers/net/wireless/intel/iwlwifi/iwlwifi.ko
> 
> My make invocation looks like this
> (start-build_5.12.0-rc6-4-amd64-clang12-lto.txt with this patch):
> 
> dileks     74706   74681  0 15:46 pts/1    00:00:00 /usr/bin/perf_5.10
> stat make V=1 -j4 LLVM=1 LLVM_IAS=1 PAHOLE=/opt/pahole/bin/pahole
> LOCALVERSION=-4-amd64-clang12-lto KBUILD_BUILD_HOST=iniza
> KBUILD_BUILD_USER=sedat.dilek@xxxxxxxxx
> KBUILD_BUILD_TIMESTAMP=2021-04-08 bindeb-pkg
> KDEB_PKGVERSION=5.12.0~rc6-4~bullseye+dileks1
> 
> Finally:
> 
> I can *NOT* boot into the kernel with this patch applied.
> 
> Personally, I do disable intentionally:
> 
> CONFIG_DEBUG_INFO_COMPRESSED=n
> 
> ...and will do independent of this patch:
> 
> CONFIG_MODULE_COMPRESS_NONE=n
> 
> As all Debian packages - generated by builddeb - are by default
> compressed with XZ.
> Compressing stuff before is counterproductive.
> This strategy generates in total smaller Debian package binaries.
> 
> This is my first analysis, I had no deeper look.
> 
> If you need further information, please let me know.
> 
> Please take a look at this.
> 
> Both linux-configs attached.

Erm, isn't it aimed for 5.13 requiring other fresh changes from the
recent kbuild tree?

-- 
  Oleksandr Natalenko (post-factum)



[Index of Archives]     [Linux&nblp;USB Development]     [Linux Media]     [Video for Linux]     [Linux Audio Users]     [Yosemite Secrets]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux