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BUG: KCSAN: data-race in delete_from_page_cache_batch / folio_mapping

write to 0xffffea000431ea98 of 8 bytes by task 13207 on cpu 0:
 page_cache_delete_batch mm/filemap.c:306 [inline]
 delete_from_page_cache_batch+0x2f6/0x6f0 mm/filemap.c:332
 truncate_inode_pages_range+0x1b8/0x690 mm/truncate.c:380
 truncate_inode_pages+0x24/0x30 mm/truncate.c:460
 kill_bdev block/bdev.c:91 [inline]
 set_blocksize+0x259/0x310 block/bdev.c:207
 sb_set_blocksize+0x7a/0x100 block/bdev.c:224
 ext4_load_super fs/ext4/super.c:5110 [inline]
 __ext4_fill_super fs/ext4/super.c:5262 [inline]
 ext4_fill_super+0x12ab/0x34e0 fs/ext4/super.c:5724
 get_tree_bdev_flags+0x28e/0x300 fs/super.c:1679
 get_tree_bdev+0x1f/0x30 fs/super.c:1702
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5756
 vfs_get_tree+0x57/0x1d0 fs/super.c:1802
 do_new_mount+0x207/0x680 fs/namespace.c:3856
 path_mount+0x4a4/0xb20 fs/namespace.c:4180
 do_mount fs/namespace.c:4193 [inline]
 __do_sys_mount fs/namespace.c:4404 [inline]
 __se_sys_mount+0x28f/0x2e0 fs/namespace.c:4381
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4381
 x64_sys_call+0xd36/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffea000431ea98 of 8 bytes by task 13199 on cpu 1:
 folio_mapping+0xa1/0x120 mm/util.c:701
 folio_evictable mm/internal.h:478 [inline]
 lru_add+0x80/0x430 mm/swap.c:136
 folio_batch_move_lru+0x174/0x230 mm/swap.c:168
 __folio_batch_add_and_move mm/swap.c:196 [inline]
 folio_add_lru+0x14a/0x1f0 mm/swap.c:505
 shmem_alloc_and_add_folio mm/shmem.c:1949 [inline]
 shmem_get_folio_gfp+0x7ab/0xd60 mm/shmem.c:2532
 shmem_fault+0xf6/0x250 mm/shmem.c:2733
 __do_fault+0xbc/0x200 mm/memory.c:5189
 do_read_fault mm/memory.c:5610 [inline]
 do_fault mm/memory.c:5744 [inline]
 do_pte_missing mm/memory.c:4251 [inline]
 handle_pte_fault mm/memory.c:6089 [inline]
 __handle_mm_fault mm/memory.c:6232 [inline]
 handle_mm_fault+0xf78/0x2be0 mm/memory.c:6401
 faultin_page mm/gup.c:1186 [inline]
 __get_user_pages+0x1036/0x1fb0 mm/gup.c:1488
 populate_vma_page_range mm/gup.c:1926 [inline]
 __mm_populate+0x243/0x3a0 mm/gup.c:2029
 mm_populate include/linux/mm.h:3348 [inline]
 vm_mmap_pgoff+0x232/0x2e0 mm/util.c:584
 ksys_mmap_pgoff+0xc2/0x310 mm/mmap.c:607
 x64_sys_call+0x1602/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:10
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff888100631e18 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 13199 Comm: syz.3.2735 Not tainted 6.15.0-syzkaller-11173-g546b1c9e93c2 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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