================================================================== BUG: KCSAN: data-race in __bio_queue_enter / blk_mq_unfreeze_queue read-write to 0xffff88810145231c of 4 bytes by task 1828 on cpu 0: __blk_mq_unfreeze_queue block/blk-mq.c:225 [inline] blk_mq_unfreeze_queue+0x34/0xb0 block/blk-mq.c:236 __loop_clr_fd+0x244/0x3c0 drivers/block/loop.c:1167 loop_clr_fd drivers/block/loop.c:1252 [inline] lo_ioctl+0xd8c/0x1290 drivers/block/loop.c:1558 blkdev_ioctl+0x20e/0x440 block/ioctl.c:614 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:856 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffff88810145231c of 4 bytes by task 2013 on cpu 1: __bio_queue_enter+0x1fa/0x510 block/blk-core.c:339 bio_queue_enter block/blk.h:76 [inline] blk_mq_get_new_requests block/blk-mq.c:2709 [inline] blk_mq_submit_bio+0x351/0xe90 block/blk-mq.c:2811 __submit_bio block/blk-core.c:595 [inline] __submit_bio_noacct_mq block/blk-core.c:672 [inline] submit_bio_noacct_nocheck+0x83d/0xaa0 block/blk-core.c:689 submit_bio_noacct+0x696/0x800 block/blk-core.c:796 submit_bio+0xfb/0x110 mpage_bio_submit fs/mpage.c:64 [inline] mpage_readahead+0x359/0x3a0 fs/mpage.c:364 blkdev_readahead+0x18/0x20 block/fops.c:386 read_pages+0xa5/0x790 mm/readahead.c:158 page_cache_ra_unbounded+0x2a8/0x2e0 mm/readahead.c:263 do_page_cache_ra mm/readahead.c:293 [inline] force_page_cache_ra+0x1c6/0x200 mm/readahead.c:324 page_cache_sync_ra+0xc8/0xf0 mm/readahead.c:695 page_cache_sync_readahead include/linux/pagemap.h:1215 [inline] filemap_get_pages mm/filemap.c:2566 [inline] filemap_read+0x3ef/0x1430 mm/filemap.c:2660 blkdev_read_iter+0x2c6/0x370 block/fops.c:598 call_read_iter include/linux/fs.h:2181 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x3a5/0x560 fs/read_write.c:470 ksys_read+0xe8/0x1a0 fs/read_write.c:607 __do_sys_read fs/read_write.c:617 [inline] __se_sys_read fs/read_write.c:615 [inline] __x64_sys_read+0x3e/0x50 fs/read_write.c:615 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0x00000001 -> 0x00000000 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 2013 Comm: udevd Not tainted 6.0.0-rc2-syzkaller-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 ================================================================== I/O error, dev loop3, sector 24 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2 I/O error, dev loop3, sector 24 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 I/O error, dev loop3, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2 Buffer I/O error on dev loop0, logical block 0, async page read loop0: unable to read partition table loop5: unable to read partition table loop5: partition table beyond EOD, truncated blk_print_req_error: 122 callbacks suppressed I/O error, dev loop4, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2 I/O error, dev loop5, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2 I/O error, dev loop5, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 I/O error, dev loop4, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 I/O error, dev loop3, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2 loop3: unable to read partition table Buffer I/O error on dev loop2, logical block 0, async page read Buffer I/O error on dev loop1, logical block 0, async page read loop2: unable to read partition table loop2: unable to read partition table loop2: partition table beyond EOD, truncated loop2: unable to read partition table