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 0xffff888237d27550 of 8 bytes by task 4370 on cpu 1:
 bh_lru_install fs/buffer.c:1345 [inline]
 find_get_block_common+0x498/0x8e0 fs/buffer.c:1410
 bdev_getblk+0x4d/0x3f0 include/linux/gfp.h:-1
 __getblk include/linux/buffer_head.h:380 [inline]
 sb_getblk include/linux/buffer_head.h:386 [inline]
 ext4_read_block_bitmap_nowait+0x168/0x680 fs/ext4/balloc.c:488
 ext4_read_block_bitmap+0x1e/0x70 fs/ext4/balloc.c:600
 ext4_mb_mark_context+0x99/0x930 fs/ext4/mballoc.c:4097
 ext4_mb_mark_diskspace_used+0x1e5/0x3b0 fs/ext4/mballoc.c:4233
 ext4_mb_new_blocks+0xa6d/0x2080 fs/ext4/mballoc.c:6335
 ext4_new_meta_blocks+0x102/0x1f0 fs/ext4/balloc.c:750
 ext4_xattr_block_set+0x13ab/0x1a60 fs/ext4/xattr.c:2123
 ext4_xattr_set_handle+0xb26/0xf80 fs/ext4/xattr.c:2457
 ext4_initxattrs+0x62/0xc0 fs/ext4/xattr_security.c:44
 security_inode_init_security+0x249/0x320 security/security.c:1344
 ext4_init_security+0x34/0x50 fs/ext4/xattr_security.c:58
 __ext4_new_inode+0x2149/0x2330 fs/ext4/ialloc.c:1324
 ext4_ext_migrate+0x401/0x9b0 fs/ext4/migrate.c:456
 __ext4_ioctl fs/ext4/ioctl.c:1688 [inline]
 ext4_ioctl+0x152d/0x3170 fs/ext4/ioctl.c:1917
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xce/0x140 fs/ioctl.c:583
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:583
 x64_sys_call+0x14b0/0x3000 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc0/0x2a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237d27550 of 8 bytes by task 3327 on cpu 0:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1551
 smp_call_function_many_cond+0x2a9/0xc30 kernel/smp.c:821
 on_each_cpu_cond_mask+0x3c/0x80 kernel/smp.c:1043
 on_each_cpu_cond include/linux/smp.h:105 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1560
 kill_bdev block/bdev.c:90 [inline]
 blkdev_flush_mapping+0x9a/0x1a0 block/bdev.c:729
 blkdev_put_whole block/bdev.c:736 [inline]
 bdev_release+0x2bf/0x3d0 block/bdev.c:1161
 blkdev_release+0x15/0x20 block/fops.c:706
 __fput+0x29b/0x650 fs/file_table.c:468
 ____fput+0x1c/0x30 fs/file_table.c:496
 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:44 [inline]
 exit_to_user_mode_loop+0x1f7/0x6f0 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x1d3/0x2a0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff888125e5c618 -> 0xffff888125e5c270

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3327 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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