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BUG: KCSAN: data-race in delete_from_page_cache_batch / folio_mapping

write to 0xffffea0004b5e918 of 8 bytes by task 27245 on cpu 0:
 page_cache_delete_batch mm/filemap.c:310 [inline]
 delete_from_page_cache_batch+0x310/0x720 mm/filemap.c:336
 truncate_inode_pages_range+0x207/0x750 mm/truncate.c:449
 truncate_inode_pages+0x24/0x30 mm/truncate.c:526
 kill_bdev block/bdev.c:90 [inline]
 set_blocksize+0x1ed/0x270 block/bdev.c:206
 sb_set_blocksize+0x93/0x170 block/bdev.c:239
 ext4_load_super fs/ext4/super.c:5263 [inline]
 __ext4_fill_super fs/ext4/super.c:5420 [inline]
 ext4_fill_super+0x13d0/0x37c0 fs/ext4/super.c:5899
 get_tree_bdev_flags+0x291/0x300 fs/super.c:1883
 get_tree_bdev+0x1f/0x30 fs/super.c:1906
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5931
 vfs_get_tree+0x57/0x1d0 fs/super.c:1943
 fc_mount fs/namespace.c:1282 [inline]
 do_new_mount_fc fs/namespace.c:3910 [inline]
 do_new_mount+0x288/0x730 fs/namespace.c:3986
 path_mount+0x4ad/0xb90 fs/namespace.c:4337
 do_mount fs/namespace.c:4350 [inline]
 __do_sys_mount fs/namespace.c:4565 [inline]
 __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4542
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4542
 x64_sys_call+0xc3b/0x2550 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffea0004b5e918 of 8 bytes by task 20630 on cpu 1:
 folio_mapping+0xa1/0xe0 mm/util.c:732
 folio_evictable mm/internal.h:655 [inline]
 lru_add+0x80/0x420 mm/folio.c:130
 folio_batch_move_lru+0x2d6/0x3d0 mm/folio.c:194
 lru_add_drain_cpu+0x65/0x2a0 mm/folio.c:630
 lru_add_drain mm/folio.c:721 [inline]
 __folio_batch_release+0x45/0xb0 mm/folio.c:1096
 folio_batch_release include/linux/folio_batch.h:101 [inline]
 shmem_undo_range+0x366/0xcc0 mm/shmem.c:1371
 shmem_truncate_range mm/shmem.c:1496 [inline]
 shmem_evict_inode+0x12d/0x4b0 mm/shmem.c:1627
 evict+0x2a5/0x510 fs/inode.c:822
 iput_final fs/inode.c:2014 [inline]
 iput+0x42b/0x5a0 fs/inode.c:2063
 dentry_unlink_inode+0x27f/0x290 fs/dcache.c:493
 dentry_kill+0x184/0x540 fs/dcache.c:840
 finish_dput+0x16/0x1d0 fs/dcache.c:1015
 dput+0x43/0x50 fs/dcache.c:1056
 end_renaming fs/namei.c:4122 [inline]
 filename_renameat2+0x478/0x6a0 fs/namei.c:6340
 __do_sys_rename fs/namei.c:6382 [inline]
 __se_sys_rename+0x4a/0x1c0 fs/namei.c:6378
 __x64_sys_rename+0x31/0x40 fs/namei.c:6378
 x64_sys_call+0x20fe/0x2550 arch/x86/include/generated/asm/syscalls_64.h:83
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff888100630528 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 20630 Comm: udevd Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
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