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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 11505 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_unmovable include/linux/buffer_head.h:369 [inline]
 ext4_getblk+0x1b6/0x510 fs/ext4/inode.c:999
 ext4_bread+0x28/0x110 fs/ext4/inode.c:1047
 ext4_quota_write+0x167/0x360 fs/ext4/super.c:7350
 qtree_write_dquot+0x149/0x300 fs/quota/quota_tree.c:462
 v2_write_dquot+0xda/0x140 fs/quota/quota_v2.c:372
 dquot_commit+0x21c/0x260 fs/quota/dquot.c:515
 ext4_write_dquot+0x126/0x1d0 fs/ext4/super.c:6962
 ext4_mark_dquot_dirty+0x95/0xd0 fs/ext4/super.c:7039
 mark_dquot_dirty fs/quota/dquot.c:373 [inline]
 mark_all_dquot_dirty fs/quota/dquot.c:413 [inline]
 __dquot_alloc_space+0x7d0/0x8a0 fs/quota/dquot.c:1743
 dquot_alloc_space_nodirty include/linux/quotaops.h:299 [inline]
 dquot_alloc_space include/linux/quotaops.h:312 [inline]
 dquot_alloc_block include/linux/quotaops.h:336 [inline]
 ext4_mb_new_blocks+0x91b/0x2080 fs/ext4/mballoc.c:6283
 ext4_ext_map_blocks+0xff5/0x38a0 fs/ext4/extents.c:4383
 ext4_map_create_blocks fs/ext4/inode.c:613 [inline]
 ext4_map_blocks+0x626/0xd20 fs/ext4/inode.c:816
 _ext4_get_block+0x10a/0x350 fs/ext4/inode.c:916
 ext4_get_block_unwritten+0x2a/0xb0 fs/ext4/inode.c:949
 ext4_block_write_begin+0x650/0xcf0 fs/ext4/inode.c:1203
 ext4_write_begin+0x636/0xe90 fs/ext4/ext4_jbd2.h:-1
 ext4_da_write_begin+0x1f0/0x6b0 fs/ext4/inode.c:3130
 generic_perform_write+0x184/0x490 mm/filemap.c:4314
 ext4_buffered_write_iter+0x1ee/0x3c0 fs/ext4/file.c:299
 ext4_file_write_iter+0x387/0xf60 fs/ext4/file.c:-1
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x52a/0x960 fs/read_write.c:686
 ksys_pwrite64 fs/read_write.c:793 [inline]
 __do_sys_pwrite64 fs/read_write.c:801 [inline]
 __se_sys_pwrite64 fs/read_write.c:798 [inline]
 __x64_sys_pwrite64+0xfd/0x150 fs/read_write.c:798
 x64_sys_call+0x9f7/0x3000 arch/x86/include/generated/asm/syscalls_64.h:19
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xca/0x2b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237d27550 of 8 bytes by task 11144 on cpu 0:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1551
 smp_call_function_many_cond+0x2a9/0xc40 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+0x131/0x1a0 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+0x1fe/0x740 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+0x1e1/0x2b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff88811aa29208 -> 0xffff88811aa29478

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 11144 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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