==================================================================
BUG: KCSAN: data-race in __percpu_counter_compare / percpu_counter_add_batch

read-write to 0xffff8881001123d0 of 8 bytes by task 27484 on cpu 0:
 percpu_counter_add_batch+0x9e/0x110 lib/percpu_counter.c:91
 percpu_counter_add include/linux/percpu_counter.h:59 [inline]
 shmem_inode_acct_block mm/shmem.c:213 [inline]
 shmem_alloc_and_acct_folio mm/shmem.c:1587 [inline]
 shmem_get_folio_gfp+0x434/0x1120 mm/shmem.c:1920
 shmem_get_folio mm/shmem.c:2051 [inline]
 shmem_write_begin+0xa6/0x1e0 mm/shmem.c:2543
 generic_perform_write+0x1c3/0x3d0 mm/filemap.c:3772
 __generic_file_write_iter+0xe6/0x290 mm/filemap.c:3900
 generic_file_write_iter+0x7d/0x1c0 mm/filemap.c:3932
 call_write_iter include/linux/fs.h:2189 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x45a/0x750 fs/read_write.c:584
 ksys_write+0xeb/0x1a0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:646
 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 0xffff8881001123d0 of 8 bytes by task 27483 on cpu 1:
 percpu_counter_read include/linux/percpu_counter.h:91 [inline]
 __percpu_counter_compare+0x2b/0x1a0 lib/percpu_counter.c:242
 percpu_counter_compare include/linux/percpu_counter.h:54 [inline]
 shmem_inode_acct_block mm/shmem.c:210 [inline]
 shmem_alloc_and_acct_folio mm/shmem.c:1587 [inline]
 shmem_get_folio_gfp+0x3fd/0x1120 mm/shmem.c:1920
 shmem_get_folio mm/shmem.c:2051 [inline]
 shmem_write_begin+0xa6/0x1e0 mm/shmem.c:2543
 generic_perform_write+0x1c3/0x3d0 mm/filemap.c:3772
 __generic_file_write_iter+0xe6/0x290 mm/filemap.c:3900
 generic_file_write_iter+0x7d/0x1c0 mm/filemap.c:3932
 call_write_iter include/linux/fs.h:2189 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x45a/0x750 fs/read_write.c:584
 ksys_write+0xeb/0x1a0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:646
 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: 0x00000000000025bb -> 0x00000000000025db

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 27483 Comm: syz-executor.0 Not tainted 6.2.0-rc7-syzkaller-00199-g420b2d431d18-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023
==================================================================