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BUG: KCSAN: data-race in __mark_inode_dirty / __writeback_single_inode

read-write to 0xffff8881004c4900 of 8 bytes by task 28 on cpu 1:
 __writeback_single_inode+0x201/0x870 fs/fs-writeback.c:1687
 writeback_sb_inodes+0x559/0xb20 fs/fs-writeback.c:1947
 __writeback_inodes_wb+0x9a/0x1a0 fs/fs-writeback.c:2018
 wb_writeback+0x270/0x720 fs/fs-writeback.c:2129
 wb_check_background_flush fs/fs-writeback.c:2199 [inline]
 wb_do_writeback fs/fs-writeback.c:2287 [inline]
 wb_workfn+0x67f/0x940 fs/fs-writeback.c:2314
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3312
 worker_thread+0x526/0x730 kernel/workqueue.c:3393
 kthread+0x1d1/0x210 kernel/kthread.c:389
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffff8881004c4900 of 8 bytes by task 55 on cpu 0:
 __mark_inode_dirty+0x19f/0x7e0 fs/fs-writeback.c:2508
 mark_buffer_dirty+0x165/0x250 fs/buffer.c:1211
 __ext4_handle_dirty_metadata+0x1fa/0x470 fs/ext4/ext4_jbd2.c:384
 ext4_do_update_inode fs/ext4/inode.c:5084 [inline]
 ext4_mark_iloc_dirty+0xaa4/0xe10 fs/ext4/inode.c:5702
 __ext4_mark_inode_dirty+0x314/0x440 fs/ext4/inode.c:5906
 __ext4_ext_dirty+0xbf/0x130 fs/ext4/extents.c:202
 ext4_convert_unwritten_extents_endio fs/ext4/extents.c:3748 [inline]
 ext4_ext_handle_unwritten_extents fs/ext4/extents.c:3873 [inline]
 ext4_ext_map_blocks+0x1ee6/0x33b0 fs/ext4/extents.c:4209
 ext4_map_blocks+0x72a/0xf50 fs/ext4/inode.c:623
 ext4_convert_unwritten_extents+0x16c/0x2c0 fs/ext4/extents.c:4846
 ext4_convert_unwritten_io_end_vec+0xa2/0x110 fs/ext4/extents.c:4885
 ext4_end_io_end fs/ext4/page-io.c:185 [inline]
 ext4_do_flush_completed_IO fs/ext4/page-io.c:258 [inline]
 ext4_end_io_rsv_work+0x17d/0x370 fs/ext4/page-io.c:272
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3312
 worker_thread+0x526/0x730 kernel/workqueue.c:3393
 kthread+0x1d1/0x210 kernel/kthread.c:389
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

value changed: 0x0000000000020084 -> 0x0000000000000004

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 55 Comm: kworker/u8:4 Not tainted 6.10.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work
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