syzbot

EXT4-fs (loop2): unmounting filesystem 00000000-0000-0000-0000-000000000000.
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BUG: KCSAN: data-race in __lru_add_drain_all / folio_add_lru

read-write to 0xffff888237d25ea8 of 1 bytes by task 5843 on cpu 1:
 folio_batch_add include/linux/pagevec.h:77 [inline]
 __folio_batch_add_and_move mm/swap.c:194 [inline]
 folio_add_lru+0xa5/0x1f0 mm/swap.c:510
 filemap_add_folio+0x129/0x1b0 mm/filemap.c:985
 do_read_cache_folio+0xd4/0x5b0 mm/filemap.c:3924
 read_cache_folio+0x3c/0x50 mm/filemap.c:3989
 read_mapping_folio include/linux/pagemap.h:991 [inline]
 read_part_sector+0x6f/0x150 block/partitions/core.c:722
 read_lba+0x100/0x1e0 block/partitions/efi.c:248
 alloc_read_gpt_header block/partitions/efi.c:316 [inline]
 is_gpt_valid+0x76/0x3e0 block/partitions/efi.c:343
 find_valid_gpt block/partitions/efi.c:618 [inline]
 efi_partition+0x181/0x1400 block/partitions/efi.c:720
 check_partition block/partitions/core.c:141 [inline]
 blk_add_partitions block/partitions/core.c:589 [inline]
 bdev_disk_changed+0x4b6/0xcb0 block/partitions/core.c:693
 loop_reread_partitions drivers/block/loop.c:439 [inline]
 loop_set_status+0x541/0x5f0 drivers/block/loop.c:1265
 loop_set_status64 drivers/block/loop.c:1361 [inline]
 lo_ioctl+0x68f/0x1350 drivers/block/loop.c:1547
 blkdev_ioctl+0x352/0x440 block/ioctl.c:705
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:598 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:584
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:584
 x64_sys_call+0x1816/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:17
 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 0xffff888237d25ea8 of 1 bytes by task 4119 on cpu 0:
 folio_batch_count include/linux/pagevec.h:56 [inline]
 cpu_needs_drain mm/swap.c:778 [inline]
 __lru_add_drain_all+0x12b/0x3f0 mm/swap.c:872
 lru_add_drain_all+0x10/0x20 mm/swap.c:888
 invalidate_bdev+0x47/0x70 block/bdev.c:101
 ext4_put_super+0x624/0x7d0 fs/ext4/super.c:1339
 generic_shutdown_super+0xe3/0x210 fs/super.c:643
 kill_block_super+0x2a/0x70 fs/super.c:1766
 ext4_kill_sb+0x42/0x80 fs/ext4/super.c:7391
 deactivate_locked_super+0x72/0x1c0 fs/super.c:474
 deactivate_super+0x97/0xa0 fs/super.c:507
 cleanup_mnt+0x269/0x2e0 fs/namespace.c:1378
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1385
 task_work_run+0x131/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xe4/0x100 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x1d6/0x200 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x02 -> 0x04

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 4119 Comm: syz-executor Tainted: G        W           6.16.0-syzkaller-12063-g37816488247d #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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