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BUG: KCSAN: data-race in blk_mq_dispatch_rq_list / blk_mq_do_dispatch_sched

write to 0xffff888101b57af8 of 4 bytes by task 25842 on cpu 1:
 blk_mq_update_dispatch_busy block/blk-mq.c:1912 [inline]
 blk_mq_dispatch_rq_list+0xf6e/0x1390 block/blk-mq.c:2155
 __blk_mq_sched_dispatch_requests+0x1ab/0x260 block/blk-mq-sched.c:306
 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+0x3b8/0x480 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+0x8a/0xa0 fs/ext4/page-io.c:378
 ext4_do_writepages+0xb3a/0x2140 fs/ext4/inode.c:2897
 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 0xffff888101b57af8 of 4 bytes by task 25707 on cpu 0:
 __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_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

value changed: 0x00000009 -> 0x00000007

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 25707 Comm: syz-executor.2 Not tainted 6.2.0-rc7-syzkaller-00018-g0983f6bf2bfc-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023
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