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BUG: KCSAN: data-race in delete_from_page_cache_batch / folio_mapping

write to 0xffffea00055a0c58 of 8 bytes by task 7942 on cpu 1:
 page_cache_delete_batch mm/filemap.c:310 [inline]
 delete_from_page_cache_batch+0x2f6/0x6f0 mm/filemap.c:336
 truncate_inode_pages_range+0x1ba/0x780 mm/truncate.c:405
 truncate_inode_pages+0x24/0x30 mm/truncate.c:485
 kill_bdev block/bdev.c:91 [inline]
 set_blocksize+0x259/0x310 block/bdev.c:207
 sb_set_blocksize+0x93/0x170 block/bdev.c:241
 sb_min_blocksize+0x53/0x60 block/bdev.c:256
 fat_fill_super+0x32d/0x1ce0 fs/fat/inode.c:1600
 vfat_fill_super+0x24/0x30 fs/fat/namei_vfat.c:1197
 get_tree_bdev_flags+0x291/0x300 fs/super.c:1691
 get_tree_bdev+0x1f/0x30 fs/super.c:1714
 vfat_get_tree+0x1c/0x30 fs/fat/namei_vfat.c:1202
 vfs_get_tree+0x57/0x1d0 fs/super.c:1751
 fc_mount fs/namespace.c:1199 [inline]
 do_new_mount_fc fs/namespace.c:3636 [inline]
 do_new_mount+0x24d/0x6a0 fs/namespace.c:3712
 path_mount+0x4ab/0xb80 fs/namespace.c:4022
 do_mount fs/namespace.c:4035 [inline]
 __do_sys_mount fs/namespace.c:4224 [inline]
 __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4201
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4201
 x64_sys_call+0x2cca/0x3000 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xca/0x2b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffea00055a0c58 of 8 bytes by task 7959 on cpu 0:
 folio_mapping+0xa1/0xe0 mm/util.c:703
 folio_evictable mm/internal.h:499 [inline]
 lru_add+0x8d/0x480 mm/swap.c:136
 folio_batch_move_lru+0x1c5/0x280 mm/swap.c:172
 __folio_batch_add_and_move mm/swap.c:196 [inline]
 folio_add_lru+0x14a/0x1f0 mm/swap.c:511
 folio_add_lru_vma+0x49/0x70 mm/swap.c:530
 do_anonymous_page mm/memory.c:5269 [inline]
 do_pte_missing mm/memory.c:4399 [inline]
 handle_pte_fault mm/memory.c:6273 [inline]
 __handle_mm_fault mm/memory.c:6411 [inline]
 handle_mm_fault+0x2858/0x2c60 mm/memory.c:6580
 faultin_page mm/gup.c:1126 [inline]
 __get_user_pages+0x1024/0x1ed0 mm/gup.c:1428
 __get_user_pages_locked mm/gup.c:1692 [inline]
 get_user_pages_remote+0x1d5/0x6c0 mm/gup.c:2614
 get_arg_page+0x8e/0x1e0 fs/exec.c:163
 copy_string_kernel+0x12c/0x1f0 fs/exec.c:566
 kernel_execve+0x3d6/0x660 fs/exec.c:1906
 call_usermodehelper_exec_async+0x197/0x250 kernel/umh.c:109
 ret_from_fork+0x149/0x290 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

value changed: 0xffff8881004817e0 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 7959 Comm: kworker/u8:54 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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