tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: b9011c7e671dbbf59bb753283ddfd03f0c9eb865 commit: f2f6175186f4ccd33a710f4cd557676a5cc60153 [690/8423] kallsyms: increase maximum kernel symbol length to 512 config: arm-randconfig-r034-20210816 (attached as .config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 44d0a99a12ec7ead4d2f5ef649ba05b40f6d463d) 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 # install arm cross compiling tool for clang build # apt-get install binutils-arm-linux-gnueabi # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commi... git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git git fetch --no-tags linux-next master git checkout f2f6175186f4ccd33a710f4cd557676a5cc60153 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): kernel/trace/trace_events_hist.c:5228:6: warning: variable 'ret' set but not used [-Wunused-but-set-variable] int ret; ^ static void hist_trigger_print_key(struct seq_file *m, ^ 2 warnings generated. vim +/hist_trigger_print_key +4594 kernel/trace/trace_events_hist.c 69a0200c2e25d6 Tom Zanussi 2016-03-03 4593 a3785b7eca8fd4 Tom Zanussi 2019-02-13 @4594 static void hist_trigger_print_key(struct seq_file *m, a3785b7eca8fd4 Tom Zanussi 2019-02-13 4595 struct hist_trigger_data *hist_data, a3785b7eca8fd4 Tom Zanussi 2019-02-13 4596 void *key, 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4597 struct tracing_map_elt *elt) 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4598 { 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4599 struct hist_field *key_field; c6afad49d127f6 Tom Zanussi 2016-03-03 4600 char str[KSYM_SYMBOL_LEN]; 69a0200c2e25d6 Tom Zanussi 2016-03-03 4601 bool multiline = false; 85013256cf0162 Tom Zanussi 2017-09-22 4602 const char *field_name; 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4603 unsigned int i; 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4604 u64 uval; 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4605 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4606 seq_puts(m, "{ "); 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4607 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4608 for_each_hist_key_field(i, hist_data) { 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4609 key_field = hist_data->fields[i]; 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4610 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4611 if (i > hist_data->n_vals) 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4612 seq_puts(m, ", "); 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4613 85013256cf0162 Tom Zanussi 2017-09-22 4614 field_name = hist_field_name(key_field, 0); 85013256cf0162 Tom Zanussi 2017-09-22 4615 0c4a6b4666e8eb Tom Zanussi 2016-03-03 4616 if (key_field->flags & HIST_FIELD_FL_HEX) { 0c4a6b4666e8eb Tom Zanussi 2016-03-03 4617 uval = *(u64 *)(key + key_field->offset); 85013256cf0162 Tom Zanussi 2017-09-22 4618 seq_printf(m, "%s: %llx", field_name, uval); c6afad49d127f6 Tom Zanussi 2016-03-03 4619 } else if (key_field->flags & HIST_FIELD_FL_SYM) { c6afad49d127f6 Tom Zanussi 2016-03-03 4620 uval = *(u64 *)(key + key_field->offset); c6afad49d127f6 Tom Zanussi 2016-03-03 4621 sprint_symbol_no_offset(str, uval); 85013256cf0162 Tom Zanussi 2017-09-22 4622 seq_printf(m, "%s: [%llx] %-45s", field_name, 85013256cf0162 Tom Zanussi 2017-09-22 4623 uval, str); c6afad49d127f6 Tom Zanussi 2016-03-03 4624 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { c6afad49d127f6 Tom Zanussi 2016-03-03 4625 uval = *(u64 *)(key + key_field->offset); c6afad49d127f6 Tom Zanussi 2016-03-03 4626 sprint_symbol(str, uval); 85013256cf0162 Tom Zanussi 2017-09-22 4627 seq_printf(m, "%s: [%llx] %-55s", field_name, 85013256cf0162 Tom Zanussi 2017-09-22 4628 uval, str); 6b4827ad028a1a Tom Zanussi 2016-03-03 4629 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { af6a29bcaf8ff2 Tom Zanussi 2018-01-15 4630 struct hist_elt_data *elt_data = elt->private_data; af6a29bcaf8ff2 Tom Zanussi 2018-01-15 4631 char *comm; af6a29bcaf8ff2 Tom Zanussi 2018-01-15 4632 af6a29bcaf8ff2 Tom Zanussi 2018-01-15 4633 if (WARN_ON_ONCE(!elt_data)) af6a29bcaf8ff2 Tom Zanussi 2018-01-15 4634 return; af6a29bcaf8ff2 Tom Zanussi 2018-01-15 4635 af6a29bcaf8ff2 Tom Zanussi 2018-01-15 4636 comm = elt_data->comm; 6b4827ad028a1a Tom Zanussi 2016-03-03 4637 6b4827ad028a1a Tom Zanussi 2016-03-03 4638 uval = *(u64 *)(key + key_field->offset); 85013256cf0162 Tom Zanussi 2017-09-22 4639 seq_printf(m, "%s: %-16s[%10llu]", field_name, 85013256cf0162 Tom Zanussi 2017-09-22 4640 comm, uval); 316961988b5ec7 Tom Zanussi 2016-03-03 4641 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { 316961988b5ec7 Tom Zanussi 2016-03-03 4642 const char *syscall_name; 316961988b5ec7 Tom Zanussi 2016-03-03 4643 316961988b5ec7 Tom Zanussi 2016-03-03 4644 uval = *(u64 *)(key + key_field->offset); 316961988b5ec7 Tom Zanussi 2016-03-03 4645 syscall_name = get_syscall_name(uval); 316961988b5ec7 Tom Zanussi 2016-03-03 4646 if (!syscall_name) 316961988b5ec7 Tom Zanussi 2016-03-03 4647 syscall_name = "unknown_syscall"; 316961988b5ec7 Tom Zanussi 2016-03-03 4648 85013256cf0162 Tom Zanussi 2017-09-22 4649 seq_printf(m, "%s: %-30s[%3llu]", field_name, 85013256cf0162 Tom Zanussi 2017-09-22 4650 syscall_name, uval); 69a0200c2e25d6 Tom Zanussi 2016-03-03 4651 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 69a0200c2e25d6 Tom Zanussi 2016-03-03 4652 seq_puts(m, "stacktrace:\n"); 69a0200c2e25d6 Tom Zanussi 2016-03-03 4653 hist_trigger_stacktrace_print(m, 69a0200c2e25d6 Tom Zanussi 2016-03-03 4654 key + key_field->offset, 69a0200c2e25d6 Tom Zanussi 2016-03-03 4655 HIST_STACKTRACE_DEPTH); 69a0200c2e25d6 Tom Zanussi 2016-03-03 4656 multiline = true; 4b94f5b7b4a5ff Namhyung Kim 2016-03-03 4657 } else if (key_field->flags & HIST_FIELD_FL_LOG2) { 85013256cf0162 Tom Zanussi 2017-09-22 4658 seq_printf(m, "%s: ~ 2^%-2llu", field_name, 4b94f5b7b4a5ff Namhyung Kim 2016-03-03 4659 *(u64 *)(key + key_field->offset)); 0c4a6b4666e8eb Tom Zanussi 2016-03-03 4660 } else if (key_field->flags & HIST_FIELD_FL_STRING) { 85013256cf0162 Tom Zanussi 2017-09-22 4661 seq_printf(m, "%s: %-50s", field_name, 76a3b0c8ac344e Tom Zanussi 2016-03-03 4662 (char *)(key + key_field->offset)); 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4663 } else { 76a3b0c8ac344e Tom Zanussi 2016-03-03 4664 uval = *(u64 *)(key + key_field->offset); 85013256cf0162 Tom Zanussi 2017-09-22 4665 seq_printf(m, "%s: %10llu", field_name, uval); 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4666 } 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4667 } 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4668 69a0200c2e25d6 Tom Zanussi 2016-03-03 4669 if (!multiline) 69a0200c2e25d6 Tom Zanussi 2016-03-03 4670 seq_puts(m, " "); 69a0200c2e25d6 Tom Zanussi 2016-03-03 4671 7ef224d1d0e3a1 Tom Zanussi 2016-03-03 4672 seq_puts(m, "}"); a3785b7eca8fd4 Tom Zanussi 2019-02-13 4673 } a3785b7eca8fd4 Tom Zanussi 2019-02-13 4674 :::::: The code at line 4594 was first introduced by commit :::::: a3785b7eca8fd45c7c39f2ddfcd67368af30c1b4 tracing: Add hist trigger snapshot() action :::::: TO: Tom Zanussi <tom.zanussi(a)linux.intel.com&gt; :::::: CC: Steven Rostedt (VMware) <rostedt(a)goodmis.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org