EXT4-fs (loop1): 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 0xffff888237d26f50 of 8 bytes by task 4125 on cpu 1:
 bh_lru_install fs/buffer.c:1345 [inline]
 find_get_block_common+0x4f0/0x960 fs/buffer.c:1410
 __find_get_block_nonatomic fs/buffer.c:1429 [inline]
 bdev_getblk+0x83/0x3b0 fs/buffer.c:1453
 __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_discard_group_preallocations+0x7b/0x8c0 fs/ext4/mballoc.c:5492
 ext4_mb_discard_preallocations fs/ext4/mballoc.c:6093 [inline]
 ext4_mb_discard_preallocations_should_retry+0xec/0x3b0 fs/ext4/mballoc.c:6114
 ext4_mb_new_blocks+0x1ca7/0x2080 fs/ext4/mballoc.c:6313
 ext4_new_meta_blocks+0xc3/0x1b0 fs/ext4/balloc.c:750
 ext4_ext_grow_indepth fs/ext4/extents.c:1330 [inline]
 ext4_ext_create_new_leaf fs/ext4/extents.c:1434 [inline]
 ext4_ext_insert_extent+0x9ec/0x29b0 fs/ext4/extents.c:2117
 ext4_split_extent_at+0x623/0x990 fs/ext4/extents.c:3255
 ext4_split_extent+0x1af/0x3b0 fs/ext4/extents.c:3406
 ext4_split_convert_extents fs/ext4/extents.c:3743 [inline]
 ext4_ext_handle_unwritten_extents fs/ext4/extents.c:3915 [inline]
 ext4_ext_map_blocks+0xb58/0x38a0 fs/ext4/extents.c:4274
 ext4_map_create_blocks fs/ext4/inode.c:609 [inline]
 ext4_map_blocks+0x5ee/0xd00 fs/ext4/inode.c:811
 mpage_map_one_extent fs/ext4/inode.c:2374 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2468 [inline]
 ext4_do_writepages+0x15e1/0x2750 fs/ext4/inode.c:2931
 ext4_writepages+0x176/0x300 fs/ext4/inode.c:3025
 do_writepages+0x1c6/0x310 mm/page-writeback.c:2634
 filemap_fdatawrite_wbc mm/filemap.c:386 [inline]
 __filemap_fdatawrite_range mm/filemap.c:419 [inline]
 file_write_and_wait_range+0x156/0x2c0 mm/filemap.c:794
 generic_buffers_fsync_noflush+0x45/0x120 fs/buffer.c:609
 ext4_fsync_nojournal fs/ext4/fsync.c:88 [inline]
 ext4_sync_file+0x1ab/0x690 fs/ext4/fsync.c:147
 vfs_fsync_range+0x10a/0x130 fs/sync.c:187
 generic_write_sync include/linux/fs.h:3042 [inline]
 ext4_buffered_write_iter+0x34f/0x3c0 fs/ext4/file.c:305
 ext4_file_write_iter+0x383/0xf00 fs/ext4/file.c:-1
 iter_file_splice_write+0x669/0x9e0 fs/splice.c:738
 do_splice_from fs/splice.c:935 [inline]
 direct_splice_actor+0x156/0x2a0 fs/splice.c:1158
 splice_direct_to_actor+0x312/0x680 fs/splice.c:1102
 do_splice_direct_actor fs/splice.c:1201 [inline]
 do_splice_direct+0xda/0x150 fs/splice.c:1227
 vfs_copy_file_range+0x978/0xf30 fs/read_write.c:1627
 __do_sys_copy_file_range fs/read_write.c:1677 [inline]
 __se_sys_copy_file_range+0x269/0x3b0 fs/read_write.c:1644
 __x64_sys_copy_file_range+0x78/0x90 fs/read_write.c:1644
 x64_sys_call+0x2c34/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:327
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237d26f50 of 8 bytes by task 3306 on cpu 0:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1551
 smp_call_function_many_cond+0x2a6/0xc60 kernel/smp.c:821
 on_each_cpu_cond_mask+0x3c/0x80 kernel/smp.c:1044
 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:712
 blkdev_put_whole block/bdev.c:719 [inline]
 bdev_release+0x2bf/0x3d0 block/bdev.c:1144
 blkdev_release+0x15/0x20 block/fops.c:699
 __fput+0x29b/0x650 fs/file_table.c:468
 ____fput+0x1c/0x30 fs/file_table.c:496
 task_work_run+0x12e/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xe4/0x100 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x1d6/0x200 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff88811a0af8f0 -> 0xffff88811a219000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3306 Comm: syz-executor Not tainted 6.17.0-rc1-syzkaller-00111-g24ea63ea3877 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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