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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 1/22/26 1:04 AM, Peter Zijlstra wrote: > I'm having trouble reproducing :-( Hi Peter, With this patch applied: diff --git a/scripts/context-analysis-suppression.txt b/scripts/context-analysis-suppression.txt index fd8951d06706..1c51b6153f08 100644 --- a/scripts/context-analysis-suppression.txt +++ b/scripts/context-analysis-suppression.txt @@ -24,6 +24,7 @@ src:*include/linux/mutex*.h=emit src:*include/linux/rcupdate.h=emit src:*include/linux/refcount.h=emit src:*include/linux/rhashtable.h=emit +src:*include/linux/rtmutex*.h=emit src:*include/linux/rwlock*.h=emit src:*include/linux/rwsem.h=emit src:*include/linux/sched*=emit and if I run the following commands: build-kernel-with-clang allmodconfig build-kernel-with-clang kernel/locking/mutex.o then the following output appears: CALL scripts/checksyscalls.sh DESCEND objtool INSTALL libsubcmd_headers CC kernel/locking/mutex.o In file included from kernel/locking/mutex.c:22: In file included from ./include/linux/ww_mutex.h:21: ./include/linux/rtmutex.h:44:25: error: reading variable 'owner' requires holding raw_spinlock '&rt_mutex_base::wait_lock' [-Werror,-Wthread-safety-analysis] 44 | return READ_ONCE(lock->owner) != NULL; | ^ ./include/linux/rtmutex.h:52:56: error: reading variable 'owner' requires holding raw_spinlock '&rt_mutex_base::wait_lock' [-Werror,-Wthread-safety-analysis] 52 | unsigned long owner = (unsigned long) READ_ONCE(lock->owner); | ^ 2 errors generated. The build-kernel-with-clang script is as follows (this may not be the recommended way to build the kernel with clang): #!/bin/bash export CC=clang export LD=ld.lld # Use LLVM's linker (optional but recommended) export AR=llvm-ar export NM=llvm-nm export OBJCOPY=llvm-objcopy export OBJDUMP=llvm-objdump export STRIP=llvm-strip export READELF=llvm-readelf make LLVM=1 CC=clang "$@" Please let me know if you need more information. Bart.