diff options
| author | Heiko Carstens <hca@linux.ibm.com> | 2026-05-19 14:03:15 +0300 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2026-05-28 13:23:22 +0300 |
| commit | 88331c4ec23a28c1006ec532fa64763d4c695e90 (patch) | |
| tree | 5525bb09dddf8f1f9245435518007d39c1c8cc53 /include/linux | |
| parent | a9e4e50519e99e5be2d69fa4eebec6a4848ae201 (diff) | |
| download | linux-88331c4ec23a28c1006ec532fa64763d4c695e90.tar.xz | |
seqlock: Allow UBSAN_ALIGNMENT to fail optimizing
With gcc-15 and gcc-16 with UBSAN_ALIGNMENT enabled the compiler fails to
inline and optimize __scoped_seqlock_bug() away on s390:
s390x-16.1.0-ld: kernel/sched/build_policy.o: in function `__scoped_seqlock_next':
/.../seqlock.h:1286:(.text+0x22030): undefined reference to `__scoped_seqlock_bug'
Fix this by adding UBSAN_ALIGNMENT to the list of config options where a
not inlined empty __scoped_seqlock_bug() is allowed.
Closes: https://lore.kernel.org/r/20260515092057.810542-1-arnd@kernel.org/
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260519110315.1385307-1-hca@linux.ibm.com
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/seqlock.h | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h index 5a40252b8334..f865491c4f2c 100644 --- a/include/linux/seqlock.h +++ b/include/linux/seqlock.h @@ -1259,14 +1259,15 @@ static __always_inline void __scoped_seqlock_cleanup(struct ss_tmp *sst) extern void __scoped_seqlock_invalid_target(void); -#if (defined(CONFIG_CC_IS_GCC) && CONFIG_GCC_VERSION < 90000) || defined(CONFIG_KASAN) +#if (defined(CONFIG_CC_IS_GCC) && CONFIG_GCC_VERSION < 90000) || \ + defined(CONFIG_KASAN) || defined(CONFIG_UBSAN_ALIGNMENT) /* * For some reason some GCC-8 architectures (nios2, alpha) have trouble * determining that the ss_done state is impossible in __scoped_seqlock_next() * below. * - * Similarly KASAN is known to confuse compilers enough to break this. But we - * don't care about code quality for KASAN builds anyway. + * Similarly KASAN and UBSAN_ALIGNMENT are known to confuse compilers enough + * to break this. But we don't care about code quality for such builds anyway. */ static inline void __scoped_seqlock_bug(void) { } #else |