EXT4-fs (loop7): unmounting filesystem 00000000-0000-0000-0000-000000000000.
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BUG: KCSAN: data-race in __find_get_block / has_bh_in_lru

read-write to 0xffff888237c2ba28 of 8 bytes by task 10117 on cpu 0:
 bh_lru_install fs/buffer.c:1337 [inline]
 __find_get_block+0x42e/0x890 fs/buffer.c:1400
 bdev_getblk+0x30/0x3b0 fs/buffer.c:1425
 ext4_sb_breadahead_unmovable+0x44/0x190 fs/ext4/super.c:271
 ext4_group_desc_init+0x59f/0x12c0 fs/ext4/super.c:4869
 __ext4_fill_super fs/ext4/super.c:5331 [inline]
 ext4_fill_super+0x21d1/0x3630 fs/ext4/super.c:5722
 get_tree_bdev_flags+0x29f/0x310 fs/super.c:1636
 get_tree_bdev+0x1f/0x30 fs/super.c:1659
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5754
 vfs_get_tree+0x56/0x1e0 fs/super.c:1814
 do_new_mount+0x227/0x690 fs/namespace.c:3560
 path_mount+0x49b/0xb30 fs/namespace.c:3887
 do_mount fs/namespace.c:3900 [inline]
 __do_sys_mount fs/namespace.c:4111 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:4088
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4088
 x64_sys_call+0x2c84/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c2ba28 of 8 bytes by task 8349 on cpu 1:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1521
 smp_call_function_many_cond+0x305/0xbb0 kernel/smp.c:838
 on_each_cpu_cond_mask+0x3c/0x90 kernel/smp.c:1052
 on_each_cpu_cond include/linux/smp.h:105 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1530
 kill_bdev block/bdev.c:90 [inline]
 blkdev_flush_mapping+0x9b/0x1a0 block/bdev.c:670
 blkdev_put_whole block/bdev.c:677 [inline]
 bdev_release+0x2f9/0x420 block/bdev.c:1102
 blkdev_release+0x15/0x20 block/fops.c:660
 __fput+0x2ac/0x640 fs/file_table.c:464
 ____fput+0x1c/0x30 fs/file_table.c:492
 task_work_run+0x13a/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xa8/0x120 kernel/entry/common.c:218
 do_syscall_64+0xd6/0x1c0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000000 -> 0xffff888106710208

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 8349 Comm: syz-executor Not tainted 6.14.0-rc7-syzkaller-00050-gfc444ada1310 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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