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BUG: KCSAN: data-race in __percpu_counter_compare / percpu_counter_add_batch

read-write to 0xffff88810004b490 of 8 bytes by task 31746 on cpu 1:
 percpu_counter_add_batch+0x9a/0x110 lib/percpu_counter.c:91
 percpu_counter_add include/linux/percpu_counter.h:56 [inline]
 shmem_inode_acct_block mm/shmem.c:223 [inline]
 shmem_alloc_and_acct_folio mm/shmem.c:1581 [inline]
 shmem_getpage_gfp+0x4b3/0x1750 mm/shmem.c:1918
 shmem_getpage mm/shmem.c:150 [inline]
 shmem_write_begin+0x84/0x110 mm/shmem.c:2496
 generic_perform_write+0x1d4/0x3f0 mm/filemap.c:3738
 __generic_file_write_iter+0xe3/0x280 mm/filemap.c:3866
 generic_file_write_iter+0x79/0x1c0 mm/filemap.c:3898
 call_write_iter include/linux/fs.h:2189 [inline]
 new_sync_write fs/read_write.c:493 [inline]
 vfs_write+0x471/0x770 fs/read_write.c:580
 ksys_write+0xe8/0x1a0 fs/read_write.c:633
 __do_sys_write fs/read_write.c:645 [inline]
 __se_sys_write fs/read_write.c:642 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:642
 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 0xffff88810004b490 of 8 bytes by task 31750 on cpu 0:
 percpu_counter_read include/linux/percpu_counter.h:72 [inline]
 __percpu_counter_compare+0x27/0x1a0 lib/percpu_counter.c:225
 percpu_counter_compare include/linux/percpu_counter.h:51 [inline]
 shmem_inode_acct_block mm/shmem.c:220 [inline]
 shmem_alloc_and_acct_folio mm/shmem.c:1581 [inline]
 shmem_getpage_gfp+0x47c/0x1750 mm/shmem.c:1918
 shmem_getpage mm/shmem.c:150 [inline]
 shmem_write_begin+0x84/0x110 mm/shmem.c:2496
 generic_perform_write+0x1d4/0x3f0 mm/filemap.c:3738
 __generic_file_write_iter+0xe3/0x280 mm/filemap.c:3866
 generic_file_write_iter+0x79/0x1c0 mm/filemap.c:3898
 call_write_iter include/linux/fs.h:2189 [inline]
 new_sync_write fs/read_write.c:493 [inline]
 vfs_write+0x471/0x770 fs/read_write.c:580
 ksys_write+0xe8/0x1a0 fs/read_write.c:633
 __do_sys_write fs/read_write.c:645 [inline]
 __se_sys_write fs/read_write.c:642 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:642
 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: 0x0000000000001ae0 -> 0x0000000000001b00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 31750 Comm: syz-executor.3 Not tainted 5.19.0-syzkaller-12689-g3bc1bc0b59d0-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
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