[linus:master] [mm] ba42b524a0: segfault_at_ip_sp_error

[kernel test robot <oliver.sang@intel.com>]

Hello,

kernel test robot noticed "segfault_at_ip_sp_error" on:

commit: ba42b524a0408b5f92bd41edaee1ea84309ab9ae ("mm: init_mlocked_on_free_v3")
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master

[test failed on linus/master      c760b3725e52403dc1b28644fb09c47a83cacea6]
[test failed on linux-next/master 3689b0ef08b70e4e03b82ebd37730a03a672853a]

in testcase: rcutorture
version: 
with following parameters:

	runtime: 300s
	test: default
	torture_type: tasks-tracing



compiler: gcc-13
test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G

(please refer to attached dmesg/kmsg for entire log/backtrace)


we didn't see clear hint in below dmesg information, but by further runs, the
issue looks quite persistent:


6c47de3be3a021d8 ba42b524a0408b5f92bd41edaee
---------------- ---------------------------
       fail:runs  %reproduction    fail:runs
           |             |             |
           :30         100%          30:30    dmesg.segfault_at_ip_sp_error


so report this FYI what we observed and captured in our tests.


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 <oliver.sang@intel.com>
| Closes: https://lore.kernel.org/oe-lkp/202405281425.92ece916-lkp@intel.com



[  OK  ] Started /etc/rc.local Compatibility.
[  OK  ] Started Getty on tty1.
[  OK  ] Reached target Login Prompts.
[  OK  ] Reached target Multi-User System.
Starting watchdog daemon...
[  351.243261][ T1844] watchdog[1844]: segfault at 0 ip 00000000 sp bfd01fac error 4 in watchdog[49d000+2000] likely on CPU 1 (core 1, socket 0)
[ 351.245577][ T1844] Code: Unable to access opcode bytes at 0xffffffd6.

Code starting with the faulting instruction
===========================================
[  351.253843][ T1846] watchdog[1846]: segfault at 0 ip 00000000 sp bfd01f9c error 4 in watchdog[49d000+2000] likely on CPU 0 (core 0, socket 0)
[ 351.256126][ T1846] Code: Unable to access opcode bytes at 0xffffffd6.

Code starting with the faulting instruction
===========================================
[FAILED] Failed to start watchdog daemon.
See 'systemctl status watchdog.service' for details.



The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20240528/202405281425.92ece916-lkp@intel.com



-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki