syzbot

==================================================================
BUG: KCSAN: data-race in delete_from_page_cache_batch / folio_mapping

write to 0xffffea0004856258 of 8 bytes by task 4627 on cpu 1:
 page_cache_delete_batch mm/filemap.c:309 [inline]
 delete_from_page_cache_batch+0x2f6/0x6f0 mm/filemap.c:335
 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 block/bdev.c:224 [inline]
 sb_min_blocksize+0xb8/0x140 block/bdev.c:239
 ext4_load_super fs/ext4/super.c:5054 [inline]
 __ext4_fill_super fs/ext4/super.c:5275 [inline]
 ext4_fill_super+0x3a1/0x3810 fs/ext4/super.c:5736
 get_tree_bdev_flags+0x291/0x300 fs/super.c:1698
 get_tree_bdev+0x1f/0x30 fs/super.c:1721
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5768
 vfs_get_tree+0x57/0x1d0 fs/super.c:1758
 fc_mount fs/namespace.c:1199 [inline]
 do_new_mount_fc fs/namespace.c:3642 [inline]
 do_new_mount+0x24d/0x660 fs/namespace.c:3718
 path_mount+0x4a5/0xb70 fs/namespace.c:4028
 do_mount fs/namespace.c:4041 [inline]
 __do_sys_mount fs/namespace.c:4229 [inline]
 __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4206
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4206
 x64_sys_call+0x2b51/0x3000 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 0xffffea0004856258 of 8 bytes by task 4607 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
 lru_add_drain_cpu+0x77/0x250 mm/swap.c:648
 lru_add_drain+0x25/0x70 mm/swap.c:737
 populate_vma_page_range mm/gup.c:1862 [inline]
 __mm_populate+0x24b/0x3a0 mm/gup.c:1963
 mm_populate include/linux/mm.h:3478 [inline]
 vm_mmap_pgoff+0x232/0x2e0 mm/util.c:586
 ksys_mmap_pgoff+0x268/0x310 mm/mmap.c:604
 x64_sys_call+0x14a3/0x3000 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: 0xffff8881005f0520 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 4607 Comm: +}[@ Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
==================================================================