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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 18846 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_get_inode_loc+0x303/0x930 fs/ext4/inode.c:4835
 ext4_get_inode_loc fs/ext4/inode.c:4963 [inline]
 ext4_reserve_inode_write+0xd7/0x250 fs/ext4/inode.c:6287
 __ext4_mark_inode_dirty+0x8c/0x3f0 fs/ext4/inode.c:6465
 ext4_dirty_inode+0x92/0xc0 fs/ext4/inode.c:6502
 __mark_inode_dirty+0x162/0x740 fs/fs-writeback.c:2595
 generic_update_time fs/inode.c:2158 [inline]
 inode_update_time fs/inode.c:2171 [inline]
 touch_atime+0x229/0x340 fs/inode.c:2243
 file_accessed include/linux/fs.h:2256 [inline]
 ext4_file_mmap_prepare+0x13a/0x1a0 fs/ext4/file.c:828
 vfs_mmap_prepare include/linux/fs.h:2060 [inline]
 call_mmap_prepare mm/vma.c:2637 [inline]
 __mmap_region mm/vma.c:2736 [inline]
 mmap_region+0xc1a/0x1d20 mm/vma.c:2830
 do_mmap+0x9b2/0xbd0 mm/mmap.c:558
 vm_mmap_pgoff+0x183/0x2d0 mm/util.c:581
 ksys_mmap_pgoff+0x267/0x310 mm/mmap.c:604
 x64_sys_call+0x16bb/0x3000 arch/x86/include/generated/asm/syscalls_64.h:10
 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 12970 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
 invalidate_bdev+0x42/0x70 block/bdev.c:100
 ext4_put_super+0x624/0x7d0 fs/ext4/super.c:1348
 generic_shutdown_super+0xe6/0x210 fs/super.c:643
 kill_block_super+0x2a/0x70 fs/super.c:1722
 ext4_kill_sb+0x42/0x80 fs/ext4/super.c:7444
 deactivate_locked_super+0x75/0x1c0 fs/super.c:474
 deactivate_super+0x97/0xa0 fs/super.c:507
 cleanup_mnt+0x2bb/0x330 fs/namespace.c:1318
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1325
 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: 0x0000000000000000 -> 0xffff888107566208

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 12970 Comm: syz-executor Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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