Hi Sebastian, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on tip/locking/core] [also build test WARNING on linus/master v6.1-rc7 next-20221128] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Sebastian-Andrzej-Siewior/Re-Crash-with-PREEMPT_RT-on-aarch64-machine/20221129-000000 patch link: https://lore.kernel.org/r/Y4Tapja2qq8HiHBZ%40linutronix.de patch subject: Re: Crash with PREEMPT_RT on aarch64 machine config: alpha-allyesconfig compiler: alpha-linux-gcc (GCC) 12.1.0 reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # https://github.com/intel-lab-lkp/linux/commit/d4aea399f0b5472dc15a4c623d99b4ae79005050 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Sebastian-Andrzej-Siewior/Re-Crash-with-PREEMPT_RT-on-aarch64-machine/20221129-000000 git checkout d4aea399f0b5472dc15a4c623d99b4ae79005050 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=alpha SHELL=/bin/bash kernel/ If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot All warnings (new ones prefixed by >>): In file included from include/asm-generic/bug.h:7, from arch/alpha/include/asm/bug.h:23, from include/linux/bug.h:5, from include/linux/thread_info.h:13, from include/asm-generic/preempt.h:5, from ./arch/alpha/include/generated/asm/preempt.h:1, from include/linux/preempt.h:78, from include/linux/spinlock.h:56, from kernel/locking/rtmutex_api.c:5: kernel/locking/rtmutex.c: In function 'rt_mutex_set_owner': >> arch/alpha/include/asm/cmpxchg.h:59:34: warning: initialization of 'struct task_struct *' from 'long unsigned int' makes pointer from integer without a cast [-Wint-conversion] 59 | __typeof__(*(ptr)) _o_ = (o); \ | ^ include/linux/once_lite.h:28:41: note: in definition of macro 'DO_ONCE_LITE_IF' 28 | bool __ret_do_once = !!(condition); \ | ^~~~~~~~~ kernel/locking/rtmutex.c:100:9: note: in expansion of macro 'WARN_ON_ONCE' 100 | WARN_ON_ONCE(cmpxchg_acquire(&lock->owner, RT_MUTEX_HAS_WAITERS, val) != RT_MUTEX_HAS_WAITERS); | ^~~~~~~~~~~~ include/linux/atomic/atomic-arch-fallback.h:35:30: note: in expansion of macro 'arch_cmpxchg' 35 | #define arch_cmpxchg_acquire arch_cmpxchg | ^~~~~~~~~~~~ include/linux/atomic/atomic-instrumented.h:1923:9: note: in expansion of macro 'arch_cmpxchg_acquire' 1923 | arch_cmpxchg_acquire(__ai_ptr, __VA_ARGS__); \ | ^~~~~~~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:100:22: note: in expansion of macro 'cmpxchg_acquire' 100 | WARN_ON_ONCE(cmpxchg_acquire(&lock->owner, RT_MUTEX_HAS_WAITERS, val) != RT_MUTEX_HAS_WAITERS); | ^~~~~~~~~~~~~~~ arch/alpha/include/asm/cmpxchg.h:59:34: note: (near initialization for '__ret_do_once') 59 | __typeof__(*(ptr)) _o_ = (o); \ | ^ include/linux/once_lite.h:28:41: note: in definition of macro 'DO_ONCE_LITE_IF' 28 | bool __ret_do_once = !!(condition); \ | ^~~~~~~~~ kernel/locking/rtmutex.c:100:9: note: in expansion of macro 'WARN_ON_ONCE' 100 | WARN_ON_ONCE(cmpxchg_acquire(&lock->owner, RT_MUTEX_HAS_WAITERS, val) != RT_MUTEX_HAS_WAITERS); | ^~~~~~~~~~~~ include/linux/atomic/atomic-arch-fallback.h:35:30: note: in expansion of macro 'arch_cmpxchg' 35 | #define arch_cmpxchg_acquire arch_cmpxchg | ^~~~~~~~~~~~ include/linux/atomic/atomic-instrumented.h:1923:9: note: in expansion of macro 'arch_cmpxchg_acquire' 1923 | arch_cmpxchg_acquire(__ai_ptr, __VA_ARGS__); \ | ^~~~~~~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:100:22: note: in expansion of macro 'cmpxchg_acquire' 100 | WARN_ON_ONCE(cmpxchg_acquire(&lock->owner, RT_MUTEX_HAS_WAITERS, val) != RT_MUTEX_HAS_WAITERS); | ^~~~~~~~~~~~~~~ arch/alpha/include/asm/cmpxchg.h:60:34: warning: initialization of 'struct task_struct *' from 'long unsigned int' makes pointer from integer without a cast [-Wint-conversion] 60 | __typeof__(*(ptr)) _n_ = (n); \ | ^ include/linux/once_lite.h:28:41: note: in definition of macro 'DO_ONCE_LITE_IF' 28 | bool __ret_do_once = !!(condition); \ | ^~~~~~~~~ kernel/locking/rtmutex.c:100:9: note: in expansion of macro 'WARN_ON_ONCE' 100 | WARN_ON_ONCE(cmpxchg_acquire(&lock->owner, RT_MUTEX_HAS_WAITERS, val) != RT_MUTEX_HAS_WAITERS); | ^~~~~~~~~~~~ include/linux/atomic/atomic-arch-fallback.h:35:30: note: in expansion of macro 'arch_cmpxchg' 35 | #define arch_cmpxchg_acquire arch_cmpxchg | ^~~~~~~~~~~~ include/linux/atomic/atomic-instrumented.h:1923:9: note: in expansion of macro 'arch_cmpxchg_acquire' 1923 | arch_cmpxchg_acquire(__ai_ptr, __VA_ARGS__); \ | ^~~~~~~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:100:22: note: in expansion of macro 'cmpxchg_acquire' 100 | WARN_ON_ONCE(cmpxchg_acquire(&lock->owner, RT_MUTEX_HAS_WAITERS, val) != RT_MUTEX_HAS_WAITERS); | ^~~~~~~~~~~~~~~ arch/alpha/include/asm/cmpxchg.h:60:34: note: (near initialization for '__ret_do_once') 60 | __typeof__(*(ptr)) _n_ = (n); \ | ^ include/linux/once_lite.h:28:41: note: in definition of macro 'DO_ONCE_LITE_IF' 28 | bool __ret_do_once = !!(condition); \ | ^~~~~~~~~ kernel/locking/rtmutex.c:100:9: note: in expansion of macro 'WARN_ON_ONCE' 100 | WARN_ON_ONCE(cmpxchg_acquire(&lock->owner, RT_MUTEX_HAS_WAITERS, val) != RT_MUTEX_HAS_WAITERS); | ^~~~~~~~~~~~ include/linux/atomic/atomic-arch-fallback.h:35:30: note: in expansion of macro 'arch_cmpxchg' 35 | #define arch_cmpxchg_acquire arch_cmpxchg | ^~~~~~~~~~~~ include/linux/atomic/atomic-instrumented.h:1923:9: note: in expansion of macro 'arch_cmpxchg_acquire' 1923 | arch_cmpxchg_acquire(__ai_ptr, __VA_ARGS__); \ | ^~~~~~~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:100:22: note: in expansion of macro 'cmpxchg_acquire' 100 | WARN_ON_ONCE(cmpxchg_acquire(&lock->owner, RT_MUTEX_HAS_WAITERS, val) != RT_MUTEX_HAS_WAITERS); | ^~~~~~~~~~~~~~~ kernel/locking/rtmutex.c:100:79: warning: comparison between pointer and integer 100 | WARN_ON_ONCE(cmpxchg_acquire(&lock->owner, RT_MUTEX_HAS_WAITERS, val) != RT_MUTEX_HAS_WAITERS); | ^~ include/linux/once_lite.h:28:41: note: in definition of macro 'DO_ONCE_LITE_IF' 28 | bool __ret_do_once = !!(condition); \ | ^~~~~~~~~ kernel/locking/rtmutex.c:100:9: note: in expansion of macro 'WARN_ON_ONCE' 100 | WARN_ON_ONCE(cmpxchg_acquire(&lock->owner, RT_MUTEX_HAS_WAITERS, val) != RT_MUTEX_HAS_WAITERS); | ^~~~~~~~~~~~ In file included from arch/alpha/include/asm/rwonce.h:33, from include/linux/compiler.h:246, from include/linux/build_bug.h:5, from include/linux/container_of.h:5, from include/linux/list.h:5, from include/linux/preempt.h:11: kernel/locking/rtmutex.c: In function 'rt_mutex_set_owner_pi': include/asm-generic/rwonce.h:55:37: warning: assignment to 'struct task_struct *' from 'long unsigned int' makes pointer from integer without a cast [-Wint-conversion] 55 | *(volatile typeof(x) *)&(x) = (val); \ | ^ include/asm-generic/rwonce.h:61:9: note: in expansion of macro '__WRITE_ONCE' 61 | __WRITE_ONCE(x, val); \ | ^~~~~~~~~~~~ kernel/locking/rtmutex.c:117:9: note: in expansion of macro 'WRITE_ONCE' 117 | WRITE_ONCE(lock->owner, val); | ^~~~~~~~~~ vim +59 arch/alpha/include/asm/cmpxchg.h 5ba840f9da1ff9 Paul Gortmaker 2012-04-02 55 96d330aff7060f Mark Rutland 2021-05-25 56 #define arch_cmpxchg(ptr, o, n) \ 5ba840f9da1ff9 Paul Gortmaker 2012-04-02 57 ({ \ fbfcd019917098 Andrea Parri 2018-02-27 58 __typeof__(*(ptr)) __ret; \ 5ba840f9da1ff9 Paul Gortmaker 2012-04-02 @59 __typeof__(*(ptr)) _o_ = (o); \ 5ba840f9da1ff9 Paul Gortmaker 2012-04-02 60 __typeof__(*(ptr)) _n_ = (n); \ fbfcd019917098 Andrea Parri 2018-02-27 61 smp_mb(); \ fbfcd019917098 Andrea Parri 2018-02-27 62 __ret = (__typeof__(*(ptr))) __cmpxchg((ptr), \ fbfcd019917098 Andrea Parri 2018-02-27 63 (unsigned long)_o_, (unsigned long)_n_, sizeof(*(ptr)));\ fbfcd019917098 Andrea Parri 2018-02-27 64 smp_mb(); \ fbfcd019917098 Andrea Parri 2018-02-27 65 __ret; \ 5ba840f9da1ff9 Paul Gortmaker 2012-04-02 66 }) 5ba840f9da1ff9 Paul Gortmaker 2012-04-02 67 -- 0-DAY CI Kernel Test Service https://01.org/lkp