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BUG: KCSAN: data-race in __find_get_block / has_bh_in_lru

read-write to 0xffff888237c26b70 of 8 bytes by task 7888 on cpu 0:
 bh_lru_install fs/buffer.c:1337 [inline]
 __find_get_block+0x432/0x880 fs/buffer.c:1400
 bdev_getblk+0x33/0x3b0 fs/buffer.c:1425
 getblk_unmovable include/linux/buffer_head.h:368 [inline]
 ext4_getblk+0x1b6/0x510 fs/ext4/inode.c:868
 ext4_bread_batch+0x5c/0x320 fs/ext4/inode.c:937
 ext4_xattr_inode_read+0x11a/0x2f0 fs/ext4/xattr.c:394
 ext4_xattr_inode_get+0xee/0x240 fs/ext4/xattr.c:547
 ext4_xattr_move_to_block fs/ext4/xattr.c:2632 [inline]
 ext4_xattr_make_inode_space fs/ext4/xattr.c:2734 [inline]
 ext4_expand_extra_isize_ea+0x8b2/0x11f0 fs/ext4/xattr.c:2822
 __ext4_expand_extra_isize+0x246/0x280 fs/ext4/inode.c:5950
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5993 [inline]
 __ext4_mark_inode_dirty+0x29d/0x3f0 fs/ext4/inode.c:6071
 __ext4_unlink+0x46c/0x630 fs/ext4/namei.c:3282
 ext4_unlink+0x100/0x2b0 fs/ext4/namei.c:3312
 vfs_unlink+0x269/0x420 fs/namei.c:4579
 do_unlinkat+0x28e/0x4c0 fs/namei.c:4643
 __do_sys_unlink fs/namei.c:4689 [inline]
 __se_sys_unlink fs/namei.c:4687 [inline]
 __x64_sys_unlink+0x2e/0x40 fs/namei.c:4687
 x64_sys_call+0x22a6/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:88
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c26b70 of 8 bytes by task 3304 on cpu 1:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1521
 smp_call_function_many_cond+0x394/0xb20 kernel/smp.c:838
 on_each_cpu_cond_mask+0x3c/0x80 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+0x9a/0x1a0 block/bdev.c:674
 blkdev_put_whole block/bdev.c:681 [inline]
 bdev_release+0x2bf/0x3d0 block/bdev.c:1106
 blkdev_release+0x15/0x20 block/fops.c:660
 __fput+0x298/0x650 fs/file_table.c:465
 ____fput+0x1c/0x30 fs/file_table.c:493
 task_work_run+0x12e/0x1a0 kernel/task_work.c:227
 resume_user_mode_work+0x6a/0x70 include/linux/resume_user_mode.h:50
 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+0x77/0xb0 kernel/entry/common.c:218
 do_syscall_64+0xdd/0x1a0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff8881061a2bc8 -> 0xffff8881061a0ea0

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3304 Comm: syz-executor Not tainted 6.15.0-rc3-syzkaller-00094-g02ddfb981de8 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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