Re: ERROR: modpost: "__popcountsi2" [fs/bcachefs/bcachefs.ko] undefined!

[Nathan Chancellor <nathan@kernel.org>]

On Thu, Aug 08, 2024 at 11:28:22AM +0800, Philip Li wrote:
> On Wed, Aug 07, 2024 at 08:36:16AM -0700, Nathan Chancellor wrote:
> > On Wed, Aug 07, 2024 at 04:43:13AM +0800, kernel test robot wrote:
> > > Hi Kent,
> > > 
> > > First bad commit (maybe != root cause):
> > > 
> > > tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> > > head:   eb5e56d1491297e0881c95824e2050b7c205f0d4
> > > commit: 9ae82fe6ace1b267005758ccfb2347a4a6aa4398 bcachefs: Inline make_bfloat() into __build_ro_aux_tree()
> > > date:   10 months ago
> > > config: arm-randconfig-002-20240805 (https://download.01.org/0day-ci/archive/20240807/202408070432.X6n56VaY-lkp@intel.com/config)
> > > compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project 423aec6573df4424f90555468128e17073ddc69e)
> > > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240807/202408070432.X6n56VaY-lkp@intel.com/reproduce)
> > > 
> > > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > > the same patch/commit), kindly add following tags
> > > | Reported-by: kernel test robot <lkp@intel.com>
> > > | Closes: https://lore.kernel.org/oe-kbuild-all/202408070432.X6n56VaY-lkp@intel.com/
> > > 
> > > All errors (new ones prefixed by >>, old ones prefixed by <<):
> > ...
> > > ERROR: modpost: "__popcountsi2" [fs/ext4/ext4.ko] undefined!
> > > ERROR: modpost: "__popcountsi2" [fs/fat/fat.ko] undefined!
> > > ERROR: modpost: "__popcountsi2" [fs/hfsplus/hfsplus.ko] undefined!
> > > ERROR: modpost: "__popcountsi2" [fs/xfs/xfs.ko] undefined!
> > > ERROR: modpost: "__popcountsi2" [fs/gfs2/gfs2.ko] undefined!
> > > >> ERROR: modpost: "__popcountsi2" [fs/bcachefs/bcachefs.ko] undefined!
> > > ERROR: modpost: "__aeabi_uldivmod" [fs/bcachefs/bcachefs.ko] undefined!
> > > ERROR: modpost: "__popcountsi2" [drivers/block/virtio_blk.ko] undefined!
> > > ERROR: modpost: "__popcountsi2" [drivers/net/ipa/ipa.ko] undefined!
> > > ERROR: modpost: "__popcountsi2" [drivers/memory/emif.ko] undefined!
> > > WARNING: modpost: suppressed 5 unresolved symbol warnings because there were too many)
> > 
> > Intel folks, can you upgrade your build of Clang main to
> > https://github.com/llvm/llvm-project/commit/4527fba9ad6bc682eceda603150bfaec65ec6916?
> 
> Got it, we will update clang to this version 4527fba9.

Thanks a lot! Is there a way to notice when a compiler upgrade causes a
lot of similar reports to be generated? If so, would it be possible to
send the reports that would be generated to only me and
llvm@lists.linux.dev? We want to get notified when there would be a lot
of reports generated after a compiler upgrade (because that usually
points to a compiler regression) but kernel developers shouldn't get
notified (since there is not anything for them to do).

> > The current revision is broken and unrelated changes are getting
> > notified. There might be one more regression that I am looking into, so
> > consider not going further than that revision.
> 
> Ok, we will keep at 4527fba9, and kindly let us know if we can move to
> latest head.

You should be able to move to the latest whenever now, the regression I
noticed was fixed with a revert (it has since been reapplied with a
fix).

Cheers,
Nathan