Re: [PATCH] gcov: use atomic counter updates to fix concurrent access crashes

[kernel test robot <lkp@intel.com>]

:::::: 
:::::: Manual check reason: "only suspicious fbc files changed"
:::::: 

BCC: lkp@intel.com
CC: oe-kbuild-all@lists.linux.dev
In-Reply-To: <20260402141831.1437357-2-khorenko@virtuozzo.com>
References: <20260402141831.1437357-2-khorenko@virtuozzo.com>
TO: Konstantin Khorenko <khorenko@virtuozzo.com>
TO: Peter Oberparleiter <oberpar@linux.ibm.com>
TO: Mikhail Zaslonko <zaslonko@linux.ibm.com>
TO: Nathan Chancellor <nathan@kernel.org>
TO: Nicolas Schier <nsc@kernel.org>
CC: Masahiro Yamada <masahiroy@kernel.org>
CC: "Thomas Weißschuh" <linux@weissschuh.net>
CC: Arnd Bergmann <arnd@arndb.de>
CC: Steffen Klassert <steffen.klassert@secunet.com>
CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: linux-kbuild@vger.kernel.org
CC: linux-kernel@vger.kernel.org
CC: netdev@vger.kernel.org
CC: Konstantin Khorenko <khorenko@virtuozzo.com>
CC: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
CC: Vasileios Almpanis <vasileios.almpanis@virtuozzo.com>
CC: Jakub Kicinski <kuba@kernel.org>

Hi Konstantin,

kernel test robot noticed the following build errors:

[auto build test ERROR on soc/for-next]
[also build test ERROR on v7.0 next-20260416]
[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/Konstantin-Khorenko/gcov-use-atomic-counter-updates-to-fix-concurrent-access-crashes/20260411-133428
base:   https://git.kernel.org/pub/scm/linux/kernel/git/soc/soc.git for-next
patch link:    https://lore.kernel.org/r/20260402141831.1437357-2-khorenko%40virtuozzo.com
patch subject: [PATCH] gcov: use atomic counter updates to fix concurrent access crashes
:::::: branch date: 6 days ago
:::::: commit date: 6 days ago
config: i386-buildonly-randconfig-005-20260417 (https://download.01.org/0day-ci/archive/20260417/202604171926.AK0Gl5MD-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260417/202604171926.AK0Gl5MD-lkp@intel.com/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 <lkp@intel.com>
| Closes: https://lore.kernel.org/r/202604171926.AK0Gl5MD-lkp@intel.com/

All errors (new ones prefixed by >>):

   ld: kernel/trace/ftrace.o: in function `symbols_cmp':
>> kernel/trace/ftrace.c:9213:(.text+0x18): undefined reference to `__atomic_fetch_add_8'
>> ld: kernel/trace/ftrace.c:9217:(.text+0x36): undefined reference to `__atomic_fetch_add_8'
   ld: kernel/trace/ftrace.o: in function `ftrace_pid_release':
   kernel/trace/ftrace.c:8961:(.text+0x5c): undefined reference to `__atomic_fetch_add_8'
   ld: kernel/trace/ftrace.c:8964:(.text+0x7a): undefined reference to `__atomic_fetch_add_8'
   ld: kernel/trace/ftrace.c:8966:(.text+0x98): undefined reference to `__atomic_fetch_add_8'
   ld: kernel/trace/ftrace.o:kernel/trace/ftrace.c:8852: more undefined references to `__atomic_fetch_add_8' follow


vim +9213 kernel/trace/ftrace.c

b0fc494fae96a7 Steven Rostedt 2008-05-12  9211  
bed0d9a50dacee Jiri Olsa      2022-05-10  9212  static int symbols_cmp(const void *a, const void *b)
bed0d9a50dacee Jiri Olsa      2022-05-10 @9213  {
bed0d9a50dacee Jiri Olsa      2022-05-10  9214  	const char **str_a = (const char **) a;
bed0d9a50dacee Jiri Olsa      2022-05-10  9215  	const char **str_b = (const char **) b;
bed0d9a50dacee Jiri Olsa      2022-05-10  9216  
bed0d9a50dacee Jiri Olsa      2022-05-10 @9217  	return strcmp(*str_a, *str_b);
bed0d9a50dacee Jiri Olsa      2022-05-10  9218  }
bed0d9a50dacee Jiri Olsa      2022-05-10  9219  

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