==================================================================
BUG: KCSAN: data-race in __count_memcg_events / mem_cgroup_css_rstat_flush

write to 0xffff888237c344c0 of 4 bytes by task 39 on cpu 1:
 mem_cgroup_css_rstat_flush+0x4ea/0x540 mm/memcontrol.c:5848
 cgroup_rstat_flush_locked+0x848/0x980 kernel/cgroup/rstat.c:245
 cgroup_rstat_flush+0x26/0x40 kernel/cgroup/rstat.c:277
 do_flush_stats mm/memcontrol.c:745 [inline]
 flush_memcg_stats_dwork+0x50/0x90 mm/memcontrol.c:782
 process_one_work kernel/workqueue.c:3254 [inline]
 process_scheduled_works+0x465/0x990 kernel/workqueue.c:3335
 worker_thread+0x526/0x730 kernel/workqueue.c:3416
 kthread+0x1d1/0x210 kernel/kthread.c:388
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read-write to 0xffff888237c344c0 of 4 bytes by task 2392 on cpu 0:
 memcg_rstat_updated mm/memcontrol.c:725 [inline]
 __count_memcg_events+0xce/0x130 mm/memcontrol.c:962
 mem_cgroup_charge_statistics mm/memcontrol.c:990 [inline]
 mem_cgroup_commit_charge+0x92/0x200 mm/memcontrol.c:2975
 charge_memcg mm/memcontrol.c:7288 [inline]
 __mem_cgroup_charge+0x75/0x100 mm/memcontrol.c:7299
 mem_cgroup_charge include/linux/memcontrol.h:691 [inline]
 shmem_alloc_and_add_folio mm/shmem.c:1683 [inline]
 shmem_get_folio_gfp+0x480/0xb70 mm/shmem.c:2061
 shmem_get_folio mm/shmem.c:2166 [inline]
 shmem_write_begin+0xa0/0x1c0 mm/shmem.c:2750
 generic_perform_write+0x1d5/0x410 mm/filemap.c:3974
 shmem_file_write_iter+0xc8/0xf0 mm/shmem.c:2926
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x771/0x8e0 fs/read_write.c:590
 ksys_write+0xeb/0x1b0 fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:652
 x64_sys_call+0x27b7/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000004 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 2392 Comm: syz-executor.3 Tainted: G        W          6.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
==================================================================
loop3: detected capacity change from 0 to 2048
EXT4-fs (loop3): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.
EXT4-fs error (device loop3): ext4_validate_block_bitmap:441: comm syz-executor.3: bg 0: block 234: padding at end of block bitmap is not set
EXT4-fs (loop3): Delayed block allocation failed for inode 18 at logical offset 0 with max blocks 2 with error 117
EXT4-fs (loop3): This should not happen!! Data will be lost