[mark:arm64/percpu-fixup 11/17] kernel/trace/ftrace.c:8628:3: warning: implicit conversion from 'unsigned long' to 'u32' (aka 'unsigned int') changes value from 18446744073709551615 to 4294967295
kernel test robot <[email protected]> Sat, 01 Aug 2026 17:41:59 +0800
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tree: https://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git arm64/percpu-fixup head: f14d3c444eacd9a722e55ff59e30cce2b1ac8985 commit: 55cddf3387a963a59fa5f7e0df28d64fc2d8aa51 [11/17] arm64: percpu: Implement preemptible read/write ops config: arm64-randconfig-002-20260801 (https://download.01.org/0day-ci/archive/20260801/[email protected]/config) compiler: clang version 21.1.8 (https://github.com/llvm/llvm-project 2078da43e25a4623cab2d0d60decddf709aaea28) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260801/[email protected]/reproduce) 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 <[email protected]> | Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/ All warnings (new ones prefixed by >>): >> kernel/trace/ftrace.c:8628:3: warning: implicit conversion from 'unsigned long' to 'u32' (aka 'unsigned int') changes value from 18446744073709551615 to 4294967295 [-Wconstant-conversion] 8628 | this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 8629 | FTRACE_PID_IGNORE); | ~~~~~~~~~~~~~~~~~~ include/linux/percpu-defs.h:500:34: note: expanded from macro 'this_cpu_write' 500 | #define this_cpu_write(pcp, val) __pcpu_size_call(this_cpu_write_, pcp, val) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/percpu-defs.h:371:11: note: expanded from macro '__pcpu_size_call' 371 | case 4: stem##4(variable, __VA_ARGS__);break; \ | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ <scratch space>:66:1: note: expanded from here 66 | this_cpu_write_4 | ^ arch/arm64/include/asm/percpu.h:282:36: note: expanded from macro 'this_cpu_write_4' 282 | _pcp_wrap(__percpu_write_32, pcp, (unsigned long)val) | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~ arch/arm64/include/asm/percpu.h:260:13: note: expanded from macro '_pcp_wrap' 260 | op(&(pcp), __VA_ARGS__); \ | ~~ ^~~~~~~~~~~ kernel/trace/ftrace.c:8898:3: warning: implicit conversion from 'unsigned long' to 'u32' (aka 'unsigned int') changes value from 18446744073709551615 to 4294967295 [-Wconstant-conversion] 8898 | this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 8899 | FTRACE_PID_IGNORE); | ~~~~~~~~~~~~~~~~~~ include/linux/percpu-defs.h:500:34: note: expanded from macro 'this_cpu_write' 500 | #define this_cpu_write(pcp, val) __pcpu_size_call(this_cpu_write_, pcp, val) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/percpu-defs.h:371:11: note: expanded from macro '__pcpu_size_call' 371 | case 4: stem##4(variable, __VA_ARGS__);break; \ | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ <scratch space>:154:1: note: expanded from here 154 | this_cpu_write_4 | ^ arch/arm64/include/asm/percpu.h:282:36: note: expanded from macro 'this_cpu_write_4' 282 | _pcp_wrap(__percpu_write_32, pcp, (unsigned long)val) | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~ arch/arm64/include/asm/percpu.h:260:13: note: expanded from macro '_pcp_wrap' 260 | op(&(pcp), __VA_ARGS__); \ | ~~ ^~~~~~~~~~~ 2 warnings generated. vim +8628 kernel/trace/ftrace.c 87354059881ce9 Steven Rostedt (Red Hat 2014-07-22 8613) 345ddcc882d889 Steven Rostedt (Red Hat 2016-04-22 8614) static void 345ddcc882d889 Steven Rostedt (Red Hat 2016-04-22 8615) ftrace_filter_pid_sched_switch_probe(void *data, bool preempt, fa2c3254d7cfff Valentin Schneider 2022-01-20 8616 struct task_struct *prev, 9c2136be0878c8 Delyan Kratunov 2022-05-11 8617 struct task_struct *next, 9c2136be0878c8 Delyan Kratunov 2022-05-11 8618 unsigned int prev_state) 978f3a45d9499c Steven Rostedt 2008-12-04 8619 { 345ddcc882d889 Steven Rostedt (Red Hat 2016-04-22 8620) struct trace_array *tr = data; 345ddcc882d889 Steven Rostedt (Red Hat 2016-04-22 8621) struct trace_pid_list *pid_list; b3b1e6ededa433 Steven Rostedt (VMware 2020-03-19 8622) struct trace_pid_list *no_pid_list; 978f3a45d9499c Steven Rostedt 2008-12-04 8623 345ddcc882d889 Steven Rostedt (Red Hat 2016-04-22 8624) pid_list = rcu_dereference_sched(tr->function_pids); b3b1e6ededa433 Steven Rostedt (VMware 2020-03-19 8625) no_pid_list = rcu_dereference_sched(tr->function_no_pids); 978f3a45d9499c Steven Rostedt 2008-12-04 8626 b3b1e6ededa433 Steven Rostedt (VMware 2020-03-19 8627) if (trace_ignore_this_task(pid_list, no_pid_list, next)) 1c5eb4481e0151 Steven Rostedt (VMware 2020-01-09 @8628) this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid, 717e3f5ebc823e Steven Rostedt (VMware 2020-03-19 8629) FTRACE_PID_IGNORE); 717e3f5ebc823e Steven Rostedt (VMware 2020-03-19 8630) else 717e3f5ebc823e Steven Rostedt (VMware 2020-03-19 8631) this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid, 717e3f5ebc823e Steven Rostedt (VMware 2020-03-19 8632) next->pid); 978f3a45d9499c Steven Rostedt 2008-12-04 8633 } 978f3a45d9499c Steven Rostedt 2008-12-04 8634 :::::: The code at line 8628 was first introduced by commit :::::: 1c5eb4481e0151d579f738175497f998840f7bbc tracing: Rename trace_buffer to array_buffer :::::: TO: Steven Rostedt (VMware) <[email protected]> :::::: CC: Steven Rostedt (VMware) <[email protected]> -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki