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BUG: KCSAN: data-race in delete_from_page_cache_batch / folio_mapping

write to 0xffffea0004dc7858 of 8 bytes by task 7778 on cpu 0:
 page_cache_delete_batch mm/filemap.c:311 [inline]
 delete_from_page_cache_batch+0x310/0x720 mm/filemap.c:337
 truncate_inode_pages_range+0x1fe/0x7e0 mm/truncate.c:405
 truncate_inode_pages+0x24/0x30 mm/truncate.c:485
 kill_bdev block/bdev.c:91 [inline]
 set_blocksize+0x1ed/0x270 block/bdev.c:207
 sb_set_blocksize+0x93/0x170 block/bdev.c:240
 sb_min_blocksize+0x53/0x60 block/bdev.c:255
 ext4_load_super fs/ext4/super.c:5133 [inline]
 __ext4_fill_super fs/ext4/super.c:5354 [inline]
 ext4_fill_super+0x398/0x37c0 fs/ext4/super.c:5824
 get_tree_bdev_flags+0x291/0x300 fs/super.c:1694
 get_tree_bdev+0x1f/0x30 fs/super.c:1717
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5856
 vfs_get_tree+0x57/0x1d0 fs/super.c:1754
 fc_mount fs/namespace.c:1193 [inline]
 do_new_mount_fc fs/namespace.c:3758 [inline]
 do_new_mount+0x288/0x8d0 fs/namespace.c:3834
 path_mount+0x4d0/0xbc0 fs/namespace.c:4154
 do_mount fs/namespace.c:4167 [inline]
 __do_sys_mount fs/namespace.c:4383 [inline]
 __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4360
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4360
 x64_sys_call+0x2d61/0x3020 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffea0004dc7858 of 8 bytes by task 7773 on cpu 1:
 folio_mapping+0xa1/0xe0 mm/util.c:732
 folio_evictable mm/internal.h:584 [inline]
 lru_add+0x8d/0x460 mm/swap.c:136
 folio_batch_move_lru+0x1d3/0x290 mm/swap.c:172
 lru_add_drain_cpu+0x66/0x210 mm/swap.c:654
 lru_add_drain+0x25/0x70 mm/swap.c:743
 lru_gen_shrink_lruvec mm/vmscan.c:5167 [inline]
 shrink_lruvec+0xba/0x1bc0 mm/vmscan.c:5932
 shrink_node_memcgs mm/vmscan.c:6171 [inline]
 shrink_node+0x697/0x20a0 mm/vmscan.c:6215
 shrink_zones mm/vmscan.c:6454 [inline]
 do_try_to_free_pages+0x408/0xc90 mm/vmscan.c:6516
 try_to_free_mem_cgroup_pages+0x201/0x420 mm/vmscan.c:6838
 try_charge_memcg+0x373/0xa10 mm/memcontrol.c:2627
 obj_cgroup_charge_pages mm/memcontrol.c:3069 [inline]
 __memcg_kmem_charge_page+0x1ce/0x3d0 mm/memcontrol.c:3113
 __alloc_frozen_pages_noprof+0x18a/0x350 mm/page_alloc.c:5238
 alloc_pages_mpol+0xb3/0x260 mm/mempolicy.c:2490
 alloc_frozen_pages_noprof mm/mempolicy.c:2561 [inline]
 alloc_pages_noprof+0x8f/0x140 mm/mempolicy.c:2581
 vm_area_alloc_pages mm/vmalloc.c:3728 [inline]
 __vmalloc_area_node mm/vmalloc.c:3878 [inline]
 __vmalloc_node_range_noprof+0xaed/0x11c0 mm/vmalloc.c:4064
 __kvmalloc_node_noprof+0x3d4/0x640 mm/slub.c:6861
 futex_hash_allocate+0x190/0x9a0 kernel/futex/core.c:1815
 futex_hash_prctl+0xd8/0xf0 kernel/futex/core.c:1961
 __do_sys_prctl kernel/sys.c:2885 [inline]
 __se_sys_prctl+0x4f4/0x1400 kernel/sys.c:2534
 __x64_sys_prctl+0x67/0x80 kernel/sys.c:2534
 x64_sys_call+0x2533/0x3020 arch/x86/include/generated/asm/syscalls_64.h:158
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff8881005f1128 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 7773 Comm: syz.5.712 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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