Re: [brauner-github:vfs.all 205/231] WARNING: modpost: vmlinux: section mismatch in reference: initramfs_test_cases+0x0 (section: .data) -> initramfs_test_extract (section: .init.text)

[David Disseldorp <ddiss@suse.de>]

On Wed, 5 Mar 2025 11:47:01 +1100, David Disseldorp wrote:

> [cc'ing linux-kselftest and kunit-dev]
> 
> Hi,
> 
> On Wed, 5 Mar 2025 01:47:55 +0800, kernel test robot wrote:
> 
> > tree:   https://github.com/brauner/linux.git vfs.all
> > head:   ea47e99a3a234837d5fea0d1a20bb2ad1eaa6dd4
> > commit: b6736cfccb582b7c016cba6cd484fbcf30d499af [205/231] initramfs_test: kunit tests for initramfs unpacking
> > config: x86_64-buildonly-randconfig-002-20250304 (https://download.01.org/0day-ci/archive/20250305/202503050109.t5Ab93hX-lkp@intel.com/config)
> > compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
> > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250305/202503050109.t5Ab93hX-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/202503050109.t5Ab93hX-lkp@intel.com/
> > 
> > All warnings (new ones prefixed by >>, old ones prefixed by <<):
> >   
> > >> WARNING: modpost: vmlinux: section mismatch in reference: initramfs_test_cases+0x0 (section: .data) -> initramfs_test_extract (section: .init.text)
> > >> WARNING: modpost: vmlinux: section mismatch in reference: initramfs_test_cases+0x30 (section: .data) -> initramfs_test_fname_overrun (section: .init.text)
> > >> WARNING: modpost: vmlinux: section mismatch in reference: initramfs_test_cases+0x60 (section: .data) -> initramfs_test_data (section: .init.text)
> > >> WARNING: modpost: vmlinux: section mismatch in reference: initramfs_test_cases+0x90 (section: .data) -> initramfs_test_csum (section: .init.text)
> > >> WARNING: modpost: vmlinux: section mismatch in reference: initramfs_test_cases+0xc0 (section: .data) -> initramfs_test_hardlink (section: .init.text)
> > >> WARNING: modpost: vmlinux: section mismatch in reference: initramfs_test_cases+0xf0 (section: .data) -> initramfs_test_many (section: .init.text)    
> 
> These new warnings are covered in the commit message. The
> kunit_test_init_section_suites() registered tests aren't in the .init
> section as debugfs entries are retained for results reporting (without
> an ability to rerun them).
> IIUC, the __kunit_init_test_suites->CONCATENATE(..., _probe) suffix is
> intended to suppress the modpost warning - @kunit-dev: any ideas why
> this isn't working as intended?

Stephen Rothwell (cc'ed) mentioned that we might be able to use
__refdata for initramfs_test_cases. The __ref* description in init.h
does indicate that it's suitable, and I now see that it's present in
kunit-example-test.c . I'll propose a patch which can be squashed in
with the existing commit.

Thanks, David