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BUG: KCSAN: data-race in __percpu_counter_compare / percpu_counter_add_batch

read-write to 0xffff888100135b50 of 8 bytes by task 15977 on cpu 1:
 percpu_counter_add_batch+0xc9/0x140 lib/percpu_counter.c:96
 shmem_inode_acct_block+0x1ee/0x220
 shmem_alloc_and_acct_folio mm/shmem.c:1676 [inline]
 shmem_get_folio_gfp+0x4ad/0xc30 mm/shmem.c:2020
 shmem_get_folio mm/shmem.c:2143 [inline]
 shmem_write_begin+0xa6/0x210 mm/shmem.c:2688
 generic_perform_write+0x1c9/0x410 mm/filemap.c:3969
 shmem_file_write_iter+0xc8/0xe0 mm/shmem.c:2865
 do_iter_write+0x4b4/0x7b0 fs/read_write.c:860
 vfs_writev+0x1a8/0x320 fs/read_write.c:933
 do_pwritev fs/read_write.c:1030 [inline]
 __do_sys_pwritev fs/read_write.c:1077 [inline]
 __se_sys_pwritev fs/read_write.c:1072 [inline]
 __x64_sys_pwritev+0x100/0x1c0 fs/read_write.c:1072
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888100135b50 of 8 bytes by task 15955 on cpu 0:
 percpu_counter_read include/linux/percpu_counter.h:101 [inline]
 __percpu_counter_compare+0x2b/0x1d0 lib/percpu_counter.c:262
 percpu_counter_compare include/linux/percpu_counter.h:64 [inline]
 shmem_inode_acct_block+0xf6/0x220 mm/shmem.c:221
 shmem_alloc_and_acct_folio mm/shmem.c:1676 [inline]
 shmem_get_folio_gfp+0x4ad/0xc30 mm/shmem.c:2020
 shmem_get_folio mm/shmem.c:2143 [inline]
 shmem_write_begin+0xa6/0x210 mm/shmem.c:2688
 generic_perform_write+0x1c9/0x410 mm/filemap.c:3969
 shmem_file_write_iter+0xc8/0xe0 mm/shmem.c:2865
 do_iter_write+0x4b4/0x7b0 fs/read_write.c:860
 vfs_writev+0x1a8/0x320 fs/read_write.c:933
 do_pwritev fs/read_write.c:1030 [inline]
 __do_sys_pwritev fs/read_write.c:1077 [inline]
 __se_sys_pwritev fs/read_write.c:1072 [inline]
 __x64_sys_pwritev+0x100/0x1c0 fs/read_write.c:1072
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000001338 -> 0x0000000000001358

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 15955 Comm: syz-executor.5 Not tainted 6.6.0-rc2-syzkaller-00386-g3aba70aed91f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
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