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

read-write to 0xffff888237d277e0 of 8 bytes by task 23656 on cpu 1:
 bh_lru_install fs/buffer.c:1230 [inline]
 find_get_block_common+0x45c/0x870 fs/buffer.c:1295
 bdev_getblk+0x4c/0x3c0 include/linux/gfp.h:-1
 __getblk include/linux/buffer_head.h:378 [inline]
 sb_getblk include/linux/buffer_head.h:384 [inline]
 __ext4_get_inode_loc+0x311/0x930 fs/ext4/inode.c:4921
 ext4_get_inode_loc fs/ext4/inode.c:5049 [inline]
 ext4_reserve_inode_write+0xd7/0x250 fs/ext4/inode.c:6506
 __ext4_mark_inode_dirty+0x8c/0x410 fs/ext4/inode.c:6694
 ext4_dirty_inode+0x92/0xc0 fs/ext4/inode.c:6731
 __mark_inode_dirty+0x164/0x700 fs/fs-writeback.c:2729
 generic_update_time fs/inode.c:2253 [inline]
 touch_atime+0x213/0x300 fs/inode.c:2328
 file_accessed include/linux/fs.h:2278 [inline]
 ext4_file_mmap_prepare+0x13a/0x1a0 fs/ext4/file.c:901
 vfs_mmap_prepare include/linux/fs.h:2070 [inline]
 call_mmap_prepare mm/vma.c:2734 [inline]
 __mmap_region mm/vma.c:2820 [inline]
 mmap_region+0xec3/0x2090 mm/vma.c:2921
 do_mmap+0xa20/0xc70 mm/mmap.c:573
 vm_mmap_pgoff+0x183/0x2d0 mm/util.c:581
 ksys_mmap_pgoff+0x250/0x310 mm/mmap.c:619
 x64_sys_call+0x23b3/0x2550 arch/x86/include/generated/asm/syscalls_64.h:10
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237d277e0 of 8 bytes by task 14525 on cpu 0:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1436
 smp_call_function_many_cond+0x2d1/0xbc0 kernel/smp.c:936
 on_each_cpu_cond_mask+0x35/0x50 kernel/smp.c:1169
 on_each_cpu_cond include/linux/smp.h:105 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1445
 kill_bdev block/bdev.c:89 [inline]
 blkdev_flush_mapping+0x94/0x1a0 block/bdev.c:757
 blkdev_put_whole block/bdev.c:764 [inline]
 bdev_release+0x2c1/0x3d0 block/bdev.c:1189
 blkdev_release+0x15/0x20 block/fops.c:682
 __fput+0x29e/0x630 fs/file_table.c:512
 ____fput+0x1c/0x30 fs/file_table.c:540
 task_work_run+0x130/0x1a0 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x1e4/0x8c0 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:336 [inline]
 do_syscall_64+0x212/0x360 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000000 -> 0xffff888106c0a120

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 14525 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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