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BUG: KCSAN: data-race in __percpu_counter_compare / percpu_counter_add_batch

read-write to 0xffff88810010b3d0 of 8 bytes by task 8638 on cpu 0:
 percpu_counter_add_batch+0x9a/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:1579 [inline]
 shmem_get_folio_gfp+0x493/0x1330 mm/shmem.c:1913
 shmem_get_folio mm/shmem.c:2044 [inline]
 shmem_write_begin+0xa2/0x1e0 mm/shmem.c:2514
 generic_perform_write+0x1d4/0x3f0 mm/filemap.c:3753
 __generic_file_write_iter+0xe3/0x280 mm/filemap.c:3881
 generic_file_write_iter+0x79/0x1c0 mm/filemap.c:3913
 do_iter_write+0x494/0x750 fs/read_write.c:861
 vfs_writev fs/read_write.c:934 [inline]
 do_writev+0x256/0x4b0 fs/read_write.c:977
 __do_sys_writev fs/read_write.c:1050 [inline]
 __se_sys_writev fs/read_write.c:1047 [inline]
 __x64_sys_writev+0x41/0x50 fs/read_write.c:1047
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88810010b3d0 of 8 bytes by task 8637 on cpu 1:
 percpu_counter_read include/linux/percpu_counter.h:91 [inline]
 __percpu_counter_compare+0x27/0x1a0 lib/percpu_counter.c:225
 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:1579 [inline]
 shmem_get_folio_gfp+0x45c/0x1330 mm/shmem.c:1913
 shmem_get_folio mm/shmem.c:2044 [inline]
 shmem_write_begin+0xa2/0x1e0 mm/shmem.c:2514
 generic_perform_write+0x1d4/0x3f0 mm/filemap.c:3753
 __generic_file_write_iter+0xe3/0x280 mm/filemap.c:3881
 generic_file_write_iter+0x79/0x1c0 mm/filemap.c:3913
 do_iter_write+0x494/0x750 fs/read_write.c:861
 vfs_writev fs/read_write.c:934 [inline]
 do_writev+0x256/0x4b0 fs/read_write.c:977
 __do_sys_writev fs/read_write.c:1050 [inline]
 __se_sys_writev fs/read_write.c:1047 [inline]
 __x64_sys_writev+0x41/0x50 fs/read_write.c:1047
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000001820 -> 0x0000000000001840

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8637 Comm: syz-executor.1 Not tainted 6.0.0-syzkaller-12189-g19d17ab7c68b-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
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