tree: https://gitee.com/openeuler/kernel.git openEuler-1.0-LTS head: 3747e12f550e11fcfb6878af5c6e88f3e4af0d1f commit: 6741506ca02825b90e77088e8fce01c3d02edfdd [23159/23203] nilfs2: fix unexpected freezing of nilfs_segctor_sync() config: x86_64-buildonly-randconfig-005-20240704 (https://download.01.org/0day-ci/archive/20240704/202407041352.YmlrzTKf-lkp@i...) compiler: gcc-12 (Ubuntu 12.3.0-9ubuntu2) 12.3.0 reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240704/202407041352.YmlrzTKf-lkp@i...)

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/202407041352.YmlrzTKf-lkp@intel.com/

Note: it may well be a FALSE warning. FWIW you are at least aware of it now. http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings

All warnings (new ones prefixed by >>):

In file included from arch/x86/include/asm/atomic.h:265, from arch/x86/include/asm/msr.h:67, from arch/x86/include/asm/processor.h:21, from arch/x86/include/asm/cpufeature.h:5, from arch/x86/include/asm/thread_info.h:53, from include/linux/thread_bits.h:22, from include/linux/thread_info.h:14, from arch/x86/include/asm/preempt.h:7, from include/linux/preempt.h:81, from include/linux/spinlock.h:51, from include/linux/mmzone.h:9, from include/linux/gfp.h:6, from include/linux/mm.h:11, from include/linux/pagemap.h:8, from fs/nilfs2/segment.c:11: In function 'atomic_set', inlined from 'nilfs_segctor_sync' at fs/nilfs2/segment.c:2175:2:

...

include/asm-generic/atomic-instrumented.h:33:9: warning: 'wait_req' may be used uninitialized [-Wmaybe-uninitialized]

33 | kasan_check_write(v, sizeof(*v)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from include/linux/compiler.h:265, from include/asm-generic/bug.h:5, from arch/x86/include/asm/bug.h:83, from include/linux/bug.h:5, from include/linux/mmdebug.h:5, from include/linux/mm.h:10: include/linux/kasan-checks.h: In function 'nilfs_segctor_sync': include/linux/kasan-checks.h:7:6: note: by argument 1 of type 'const volatile void *' to 'kasan_check_write' declared here 7 | void kasan_check_write(const volatile void *p, unsigned int size); | ^~~~~~~~~~~~~~~~~ fs/nilfs2/segment.c:2170:43: note: 'wait_req' declared here 2170 | struct nilfs_segctor_wait_request wait_req; | ^~~~~~~~

vim +/wait_req +33 include/asm-generic/atomic-instrumented.h

b06ed71a624ba0 Dmitry Vyukov 2018-01-29 30 b06ed71a624ba0 Dmitry Vyukov 2018-01-29 31 static __always_inline void atomic_set(atomic_t *v, int i) b06ed71a624ba0 Dmitry Vyukov 2018-01-29 32 { a35353bb9eb199 Dmitry Vyukov 2018-01-29 @33 kasan_check_write(v, sizeof(*v)); b06ed71a624ba0 Dmitry Vyukov 2018-01-29 34 arch_atomic_set(v, i); b06ed71a624ba0 Dmitry Vyukov 2018-01-29 35 } b06ed71a624ba0 Dmitry Vyukov 2018-01-29 36

:::::: The code at line 33 was first introduced by commit :::::: a35353bb9eb1990a44a0d7585f99e9589bcdb682 locking/atomic, asm-generic: Add KASAN instrumentation to atomic operations

:::::: TO: Dmitry Vyukov dvyukov@google.com :::::: CC: Ingo Molnar mingo@kernel.org