================================================================== BUG: KCSAN: data-race in blk_mq_dispatch_rq_list / blk_mq_do_dispatch_sched read-write to 0xffff888100cc98f8 of 4 bytes by task 9141 on cpu 0: blk_mq_update_dispatch_busy block/blk-mq.c:1912 [inline] blk_mq_dispatch_rq_list+0x11d3/0x1390 block/blk-mq.c:2152 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:173 [inline] blk_mq_do_dispatch_sched+0x4de/0x820 block/blk-mq-sched.c:187 __blk_mq_sched_dispatch_requests+0x1c1/0x260 blk_mq_sched_dispatch_requests+0x93/0x100 block/blk-mq-sched.c:339 __blk_mq_run_hw_queue+0x8b/0x150 block/blk-mq.c:2174 __blk_mq_delay_run_hw_queue+0xb3/0x2f0 block/blk-mq.c:2250 blk_mq_run_hw_queue+0x1c2/0x350 block/blk-mq.c:2298 blk_mq_get_tag+0x479/0x590 block/blk-mq-tag.c:163 __blk_mq_alloc_requests+0x5a8/0x6d0 block/blk-mq.c:526 blk_mq_get_new_requests block/blk-mq.c:2878 [inline] blk_mq_submit_bio+0x4ad/0xea0 block/blk-mq.c:2973 __submit_bio+0xd2/0x150 block/blk-core.c:602 __submit_bio_noacct_mq block/blk-core.c:679 [inline] submit_bio_noacct_nocheck+0x41c/0x480 block/blk-core.c:696 submit_bio_noacct+0x7f1/0xa50 block/blk-core.c:802 submit_bio+0x101/0x110 block/blk-core.c:838 ext4_io_submit fs/ext4/page-io.c:378 [inline] io_submit_add_bh fs/ext4/page-io.c:420 [inline] ext4_bio_write_page+0x88f/0xf10 fs/ext4/page-io.c:564 mpage_submit_page fs/ext4/inode.c:2129 [inline] mpage_map_and_submit_buffers fs/ext4/inode.c:2374 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2513 [inline] ext4_do_writepages+0x138c/0x2140 fs/ext4/inode.c:2877 ext4_writepages+0x127/0x250 fs/ext4/inode.c:2965 do_writepages+0x1c7/0x330 mm/page-writeback.c:2581 filemap_fdatawrite_wbc+0xdb/0xf0 mm/filemap.c:388 __filemap_fdatawrite_range mm/filemap.c:421 [inline] __filemap_fdatawrite mm/filemap.c:427 [inline] filemap_flush+0x95/0xc0 mm/filemap.c:454 ext4_alloc_da_blocks+0x50/0x130 fs/ext4/inode.c:3219 ext4_release_file+0x5f/0x1c0 fs/ext4/file.c:158 __fput+0x245/0x570 fs/file_table.c:320 ____fput+0x15/0x20 fs/file_table.c:348 task_work_run+0x123/0x160 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0x5a6/0x1690 kernel/exit.c:867 do_group_exit+0x101/0x150 kernel/exit.c:1012 get_signal+0xea9/0xfe0 kernel/signal.c:2859 arch_do_signal_or_restart+0x89/0x2b0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop+0x6d/0xe0 kernel/entry/common.c:168 exit_to_user_mode_prepare+0x6a/0xa0 kernel/entry/common.c:203 irqentry_exit_to_user_mode+0x9/0x20 kernel/entry/common.c:309 irqentry_exit+0x12/0x40 kernel/entry/common.c:412 exc_general_protection+0x339/0x4c0 arch/x86/kernel/traps.c:728 asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:564 read to 0xffff888100cc98f8 of 4 bytes by task 41 on cpu 1: __blk_mq_do_dispatch_sched block/blk-mq-sched.c:100 [inline] blk_mq_do_dispatch_sched+0xc8/0x820 block/blk-mq-sched.c:187 __blk_mq_sched_dispatch_requests+0x1c1/0x260 blk_mq_sched_dispatch_requests+0x93/0x100 block/blk-mq-sched.c:339 __blk_mq_run_hw_queue+0x8b/0x150 block/blk-mq.c:2174 blk_mq_run_work_fn+0x41/0x50 block/blk-mq.c:2473 process_one_work+0x3e6/0x750 kernel/workqueue.c:2289 worker_thread+0x5ef/0xa10 kernel/workqueue.c:2436 kthread+0x1ac/0x1e0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 value changed: 0x00000007 -> 0x00000008 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 41 Comm: kworker/1:1H Not tainted 6.2.0-rc8-syzkaller-00083-g3ac88fa4605e-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 Workqueue: kblockd blk_mq_run_work_fn ==================================================================