[linus:master] [shmem,percpu_counter] beb9868628: BUG:KCSAN:data-race_in__percpu_counter_limited_add/__percpu_counter_limited_add

From: kernel test robot
Date: Fri May 31 2024 - 01:53:03 EST




Hello,

kernel test robot noticed "BUG:KCSAN:data-race_in__percpu_counter_limited_add/__percpu_counter_limited_add" on:

commit: beb9868628445306958fd7b2da1cd369a4a381cc ("shmem,percpu_counter: add _limited_add(fbc, limit, amount)")
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master

[test failed on linus/master 2bfcfd584ff5ccc8bb7acde19b42570414bf880b]
[test failed on linux-next/master 6dc544b66971c7f9909ff038b62149105272d26a]

in testcase: trinity
version:
with following parameters:

runtime: 300s
group: group-01
nr_groups: 5



compiler: gcc-12
test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G

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


in our tests,
dmesg.BUG:KCSAN:data-race_in__percpu_counter_limited_add/__percpu_counter_limited_add
does not always happen, 88 times out of 150 runs as below.


3022fd7af9604d44 beb9868628445306958fd7b2da1
---------------- ---------------------------
fail:runs %reproduction fail:runs
| | |
:60 147% 88:150 dmesg.BUG:KCSAN:data-race_in__percpu_counter_limited_add/__percpu_counter_limited_add



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@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-lkp/202405311100.d46f2cc1-lkp@xxxxxxxxx



[ 301.127451][ T4651] ==================================================================
[ 301.128485][ T4651] BUG: KCSAN: data-race in __percpu_counter_limited_add / __percpu_counter_limited_add
[ 301.129715][ T4651]
[ 301.130014][ T4651] write to 0xffff88810ffc3450 of 8 bytes by task 4674 on cpu 0:
[ 301.130981][ T4651] __percpu_counter_limited_add (lib/percpu_counter.c:325)
[ 301.131692][ T4651] shmem_inode_acct_blocks (mm/shmem.c:220)
[ 301.132319][ T4651] shmem_get_folio_gfp+0x3a9/0x750
[ 301.133054][ T4651] shmem_write_begin (mm/shmem.c:2135 mm/shmem.c:2692)
[ 301.133690][ T4651] generic_perform_write (mm/filemap.c:3962)
[ 301.134347][ T4651] shmem_file_write_iter (mm/shmem.c:2868)
[ 301.134956][ T4651] do_iter_readv_writev (include/linux/fs.h:1956 fs/read_write.c:735)
[ 301.135628][ T4651] do_iter_write (fs/read_write.c:860)
[ 301.136178][ T4651] vfs_writev (fs/read_write.c:933)
[ 301.136716][ T4651] __x64_sys_pwritev2 (fs/read_write.c:1030 fs/read_write.c:1089 fs/read_write.c:1080 fs/read_write.c:1080)
[ 301.139719][ T4651] do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
[ 301.140316][ T4651] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
[ 301.141129][ T4651]
[ 301.141465][ T4651] read to 0xffff88810ffc3450 of 8 bytes by task 4651 on cpu 1:
[ 301.142436][ T4651] __percpu_counter_limited_add (lib/percpu_counter.c:302 (discriminator 1))
[ 301.143222][ T4651] shmem_inode_acct_blocks (mm/shmem.c:220)
[ 301.143931][ T4651] shmem_get_folio_gfp+0x3a9/0x750
[ 301.144696][ T4651] shmem_write_begin (mm/shmem.c:2135 mm/shmem.c:2692)
[ 301.145370][ T4651] generic_perform_write (mm/filemap.c:3962)
[ 301.146112][ T4651] shmem_file_write_iter (mm/shmem.c:2868)
[ 301.146697][ T4651] do_iter_readv_writev (include/linux/fs.h:1956 fs/read_write.c:735)
[ 301.147330][ T4651] do_iter_write (fs/read_write.c:860)
[ 301.147918][ T4651] vfs_writev (fs/read_write.c:933)
[ 301.148480][ T4651] __x64_sys_pwritev2 (fs/read_write.c:1030 fs/read_write.c:1089 fs/read_write.c:1080 fs/read_write.c:1080)
[ 301.149047][ T4651] do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
[ 301.149629][ T4651] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
[ 301.150358][ T4651]
[ 301.150643][ T4651] value changed: 0x0000000000059e35 -> 0x0000000000059e56
[ 301.151483][ T4651]
[ 301.151778][ T4651] Reported by Kernel Concurrency Sanitizer on:
[ 301.152559][ T4651] CPU: 1 PID: 4651 Comm: trinity-c7 Not tainted 6.6.0-rc4-00235-gbeb986862844 #1
[ 301.153676][ T4651] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
[ 301.154962][ T4651] ==================================================================

..

[ 341.345671][ T4958] ==================================================================
[ 341.346844][ T4958] BUG: KCSAN: data-race in __percpu_counter_limited_add / __percpu_counter_limited_add
[ 341.348131][ T4958]
[ 341.348468][ T4958] write to 0xffff88810ffc3450 of 8 bytes by task 4967 on cpu 0:
[ 341.349472][ T4958] __percpu_counter_limited_add (lib/percpu_counter.c:325)
[ 341.350219][ T4958] shmem_inode_acct_blocks (mm/shmem.c:220)
[ 341.350902][ T4958] shmem_get_folio_gfp+0x3a9/0x750
[ 341.351630][ T4958] shmem_write_begin (mm/shmem.c:2135 mm/shmem.c:2692)
[ 341.352270][ T4958] generic_perform_write (mm/filemap.c:3962)
[ 341.352893][ T4958] shmem_file_write_iter (mm/shmem.c:2868)
[ 341.353521][ T4958] do_iter_readv_writev (include/linux/fs.h:1956 fs/read_write.c:735)
[ 341.354170][ T4958] do_iter_write (fs/read_write.c:860)
[ 341.354738][ T4958] vfs_writev (fs/read_write.c:933)
[ 341.355289][ T4958] __x64_sys_pwritev2 (fs/read_write.c:1030 fs/read_write.c:1089 fs/read_write.c:1080 fs/read_write.c:1080)
[ 341.355926][ T4958] do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
[ 341.356511][ T4958] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
[ 341.357277][ T4958]
[ 341.357592][ T4958] read to 0xffff88810ffc3450 of 8 bytes by task 4958 on cpu 1:
[ 341.358556][ T4958] __percpu_counter_limited_add (lib/percpu_counter.c:302 (discriminator 1))
[ 341.359312][ T4958] shmem_inode_acct_blocks (mm/shmem.c:220)
[ 341.360021][ T4958] shmem_get_folio_gfp+0x3a9/0x750
[ 341.360772][ T4958] shmem_write_begin (mm/shmem.c:2135 mm/shmem.c:2692)
[ 341.361417][ T4958] generic_perform_write (mm/filemap.c:3962)
[ 341.362106][ T4958] shmem_file_write_iter (mm/shmem.c:2868)
[ 341.362751][ T4958] do_iter_readv_writev (include/linux/fs.h:1956 fs/read_write.c:735)
[ 341.363443][ T4958] do_iter_write (fs/read_write.c:860)
[ 341.364025][ T4958] vfs_writev (fs/read_write.c:933)
[ 341.364585][ T4958] __x64_sys_pwritev2 (fs/read_write.c:1030 fs/read_write.c:1089 fs/read_write.c:1080 fs/read_write.c:1080)
[ 341.365226][ T4958] do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
[ 341.365824][ T4958] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
[ 341.366587][ T4958]
[ 341.366921][ T4958] value changed: 0x000000000008c0e8 -> 0x000000000008c109
[ 341.367883][ T4958]
[ 341.368191][ T4958] Reported by Kernel Concurrency Sanitizer on:
[ 341.369014][ T4958] CPU: 1 PID: 4958 Comm: trinity-c5 Not tainted 6.6.0-rc4-00235-gbeb986862844 #1
[ 341.370255][ T4958] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
[ 341.371512][ T4958] ==================================================================



The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20240531/202405311100.d46f2cc1-lkp@xxxxxxxxx



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