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BUG: KCSAN: data-race in find_get_block_common / has_bh_in_lru

read-write to 0xffff888237d27760 of 8 bytes by task 3021 on cpu 1:
 bh_lru_install fs/buffer.c:1342 [inline]
 find_get_block_common+0x459/0x8a0 fs/buffer.c:1407
 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_get_inode_loc+0x303/0x930 fs/ext4/inode.c:4802
 ext4_get_inode_loc+0x66/0xe0 fs/ext4/inode.c:4930
 ext4_xattr_ibody_get+0x92/0x2d0 fs/ext4/xattr.c:648
 ext4_xattr_get+0xdc/0x470 fs/ext4/xattr.c:709
 ext4_get_acl+0x84/0x480 fs/ext4/acl.c:165
 __get_acl+0x17b/0x3a0 fs/posix_acl.c:159
 get_inode_acl+0x24/0x30 fs/posix_acl.c:184
 check_acl+0x3a/0x140 fs/namei.c:385
 acl_permission_check fs/namei.c:471 [inline]
 generic_permission+0x370/0x470 fs/namei.c:524
 do_inode_permission fs/namei.c:585 [inline]
 inode_permission+0x17a/0x3b0 fs/namei.c:648
 may_open+0x255/0x350 fs/namei.c:4254
 do_open fs/namei.c:4675 [inline]
 path_openat+0x1a59/0x2050 fs/namei.c:4836
 do_file_open+0x16c/0x290 fs/namei.c:4865
 do_sys_openat2+0x94/0x130 fs/open.c:1366
 do_sys_open fs/open.c:1372 [inline]
 __do_sys_openat fs/open.c:1388 [inline]
 __se_sys_openat fs/open.c:1383 [inline]
 __x64_sys_openat+0xf2/0x120 fs/open.c:1383
 x64_sys_call+0x1e39/0x3020 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237d27760 of 8 bytes by task 4321 on cpu 0:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1548
 smp_call_function_many_cond+0x2c1/0xc30 kernel/smp.c:821
 on_each_cpu_cond_mask+0x3c/0x80 kernel/smp.c:1043
 on_each_cpu_cond include/linux/smp.h:106 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1557
 kill_bdev block/bdev.c:90 [inline]
 blkdev_flush_mapping+0x9a/0x1a0 block/bdev.c:728
 blkdev_put_whole block/bdev.c:735 [inline]
 bdev_release+0x2bf/0x3d0 block/bdev.c:1160
 blkdev_release+0x15/0x20 block/fops.c:705
 __fput+0x29b/0x650 fs/file_table.c:469
 ____fput+0x1c/0x30 fs/file_table.c:497
 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:67 [inline]
 exit_to_user_mode_loop+0x1f4/0x6f0 kernel/entry/common.c:98
 __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 include/linux/entry-common.h:325 [inline]
 do_syscall_64+0x249/0x370 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff888107a41c98 -> 0xffff888100421138

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 4321 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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