Re: [PATCH] selftests: vDSO: don't include generated headers for chacha test

[Aishwarya TCV <aishwarya.tcv@arm.com>]

On 04/09/2024 16:58, Jason A. Donenfeld wrote:
> It's not correct to use $(top_srcdir) for generated header files, for
> builds that are done out of tree via O=, and $(objtree) isn't valid in
> the selftests context. Instead, just obviate the need for these
> generated header files by defining empty stubs in tools/include/asm,
> which is the same thing that's done for rwlock.h.
> 
> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

Hi Jason,

Currently when building kselftest against next-master with arm64 arch
and defconfig+kselftest-kvm, few errors due to undeclared variables are
observed in our CI. Hence unable to build and run kselftest-kvm tests.

I ran a bisect that pointed at this patch. I have attached the bisect
log and full log from failure below.

Failure log:
-----------
https://storage.kernelci.org/next/master/next-20240906/arm64/defconfig+kselftest/gcc-12/logs/kselftest.log


In file included from /tmp/kci/linux/build/usr/include/linux/kvm.h:15,
                 from include/kvm_util.h:14,
                 from aarch64/aarch32_id_regs.c:13:
aarch64/aarch32_id_regs.c:70:27: error: ‘SYS_ID_PFR0_EL1’ undeclared
here (not in a function); did you mean ‘SYS_ICC_AP1R0_EL1’?
   70 |         KVM_ARM64_SYS_REG(SYS_ID_PFR0_EL1),
      |                           ^~~~~~~~~~~~~~~
.
.
aarch64/aarch32_id_regs.c:149:44: error: ‘ID_AA64PFR0_EL1_EL0_MASK’
undeclared (first use in this function)
  149 |         el0 = FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_EL0),
val);
      |                                            ^~~~~~~~~~~~~~~~~~~
/tmp/kci/linux/tools/testing/selftests/../../../tools/include/linux/compiler.h:17:23:
note: in definition of macro ‘__compiletime_assert’
   17 |                 if (!(condition))
       \
      |                       ^~~~~~~~~
/tmp/kci/linux/tools/testing/selftests/../../../tools/include/linux/compiler.h:37:9:
note: in expansion of macro ‘_compiletime_assert’
   37 |         _compiletime_assert(condition, msg,
__compiletime_assert_, __COUNTER__)
      |         ^~~~~~~~~~~~~~~~~~~
/tmp/kci/linux/tools/testing/selftests/../../../tools/include/linux/build_bug.h:39:37:
note: in expansion of macro ‘compiletime_assert’
   39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
      |                                     ^~~~~~~~~~~~~~~~~~
/tmp/kci/linux/tools/testing/selftests/../../../tools/include/linux/bitfield.h:62:17:
note: in expansion of macro ‘BUILD_BUG_ON_MSG’
   62 |                 BUILD_BUG_ON_MSG(!__builtin_constant_p(_mask),
       \
      |                 ^~~~~~~~~~~~~~~~
/tmp/kci/linux/tools/testing/selftests/../../../tools/include/linux/bitfield.h:125:17:
note: in expansion of macro ‘__BF_FIELD_CHECK’
  125 |                 __BF_FIELD_CHECK(_mask, _reg, 0U, "FIELD_GET:
");       \
      |                 ^~~~~~~~~~~~~~~~
aarch64/aarch32_id_regs.c:149:15: note: in expansion of macro ‘FIELD_GET’
  149 |         el0 = FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_EL0),
val);
      |               ^~~~~~~~~
aarch64/aarch32_id_regs.c:149:25: note: in expansion of macro
‘ARM64_FEATURE_MASK’
  149 |         el0 = FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_EL0),
val);
      |                         ^~~~~~~~~~~~~~~~~~
At top level:
cc1: note: unrecognized command-line option
‘-Wno-gnu-variable-sized-type-not-at-end’ may have been intended to
silence earlier diagnostics
make[4]: *** [Makefile:299:
/tmp/kci/linux/build/kselftest/kvm/aarch64/aarch32_id_regs.o] Error 1
make[4]: Leaving directory '/tmp/kci/linux/tools/testing/selftests/kvm'


Bisect log:
-----------
git bisect start
# good: [da3ea35007d0af457a0afc87e84fddaebc4e0b63] Linux 6.11-rc7
git bisect good da3ea35007d0af457a0afc87e84fddaebc4e0b63
# bad: [6708132e80a2ced620bde9b9c36e426183544a23] Add linux-next
specific files for 20240910
git bisect bad 6708132e80a2ced620bde9b9c36e426183544a23
# good: [b66d58fce82c825b3dbb57a46b9a74f081ef7ec7] Merge branch 'main'
of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git
git bisect good b66d58fce82c825b3dbb57a46b9a74f081ef7ec7
# good: [a636a90415dbc59f005369e3053996f859f0af50] Merge branch
'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/libata/linux
git bisect good a636a90415dbc59f005369e3053996f859f0af50
# good: [8e5ac35ddecbeddce79e915c226baaf577a2be6e] Merge branch
'driver-core-next' of
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git
git bisect good 8e5ac35ddecbeddce79e915c226baaf577a2be6e
# good: [e9643b5e3a2f5f0607d3b71bebe22cc6d29b534c] Merge branch
'counter-next' of
git://git.kernel.org/pub/scm/linux/kernel/git/wbg/counter.git
git bisect good e9643b5e3a2f5f0607d3b71bebe22cc6d29b534c
# good: [150b9788d677f54650e1aceffde0eead5986baab] Merge branch
'pwm/for-next' of
git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux.git
git bisect good 150b9788d677f54650e1aceffde0eead5986baab
# good: [b4c533038255b85a068b622f888e0a9e8096a199] Merge branch
'slab/for-next' of
git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab.git
git bisect good b4c533038255b85a068b622f888e0a9e8096a199
# bad: [b9a71f4a0f68d11be247fd7ff82d7a72e3503181] Merge branch
'rust-next' of https://github.com/Rust-for-Linux/linux.git
git bisect bad b9a71f4a0f68d11be247fd7ff82d7a72e3503181
# good: [aeb0e24abbebebff3b5ac65486c933d0ecd5cf81] kbuild: rust: replace
proc macros dependency on `core.o` with the version text
git bisect good aeb0e24abbebebff3b5ac65486c933d0ecd5cf81
# good: [b75eb4403eefde26f8f71a66dcc609a091fa40e6] random: vDSO:
minimize and simplify header includes
git bisect good b75eb4403eefde26f8f71a66dcc609a091fa40e6
# bad: [5bc8fca346995ada9a379369492620f5d1991a08] powerpc/vdso32: Add
crtsavres
git bisect bad 5bc8fca346995ada9a379369492620f5d1991a08
# good: [c2066b95688ab8d1c296d44e325f54630688e6a7] selftests: vDSO: also
test counter in vdso_test_chacha
git bisect good c2066b95688ab8d1c296d44e325f54630688e6a7
# bad: [a727d213f81c9ffba79e161f59e120c92b9ddb1b] selftests: vDSO: don't
include generated headers for chacha test
git bisect bad a727d213f81c9ffba79e161f59e120c92b9ddb1b
# good: [67e5214e51e767d4e04d9eb5754d320c918c5ed8] arm64: vDSO: Wire up
getrandom() vDSO implementation
git bisect good 67e5214e51e767d4e04d9eb5754d320c918c5ed8
# first bad commit: [a727d213f81c9ffba79e161f59e120c92b9ddb1b]
selftests: vDSO: don't include generated headers for chacha test

Thanks,
Aishwarya