================================================================== BUG: KCSAN: data-race in __delayacct_blkio_end / __delayacct_blkio_start write to 0xffff88810159b8c8 of 8 bytes by task 10177 on cpu 0: __delayacct_blkio_start+0x35/0x40 kernel/delayacct.c:61 delayacct_blkio_start include/linux/delayacct.h:119 [inline] __schedule+0x18c/0x550 kernel/sched/core.c:4485 schedule+0x7f/0xb0 kernel/sched/core.c:4601 io_schedule+0x3b/0x50 kernel/sched/core.c:6295 bit_wait_io+0x8/0x40 kernel/sched/wait_bit.c:209 __wait_on_bit kernel/sched/wait_bit.c:49 [inline] out_of_line_wait_on_bit+0xb6/0x110 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] __wait_on_buffer fs/buffer.c:122 [inline] wait_on_buffer include/linux/buffer_head.h:354 [inline] __bread_slow fs/buffer.c:1210 [inline] __bread_gfp+0x18b/0x210 fs/buffer.c:1402 sb_bread include/linux/buffer_head.h:301 [inline] fat__get_entry fs/fat/dir.c:100 [inline] fat_get_entry+0x47c/0x5f0 fs/fat/dir.c:128 fat_get_short_entry fs/fat/dir.c:873 [inline] fat_subdirs+0x10c/0x1b0 fs/fat/dir.c:939 fat_read_root fs/fat/inode.c:1412 [inline] fat_fill_super+0x2607/0x2a00 fs/fat/inode.c:1862 msdos_fill_super+0x29/0x30 fs/fat/namei_msdos.c:653 mount_bdev+0x1e2/0x280 fs/super.c:1419 msdos_mount+0x2d/0x40 fs/fat/namei_msdos.c:660 legacy_get_tree+0x70/0xc0 fs/fs_context.c:592 vfs_get_tree+0x4a/0x190 fs/super.c:1549 do_new_mount fs/namespace.c:2875 [inline] path_mount+0x119d/0x1c10 fs/namespace.c:3205 do_mount fs/namespace.c:3218 [inline] __do_sys_mount fs/namespace.c:3426 [inline] __se_sys_mount+0x23d/0x2e0 fs/namespace.c:3403 __x64_sys_mount+0x63/0x70 fs/namespace.c:3403 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff88810159b8c8 of 8 bytes by interrupt on cpu 1: delayacct_end kernel/delayacct.c:48 [inline] __delayacct_blkio_end+0x70/0xf0 kernel/delayacct.c:82 delayacct_blkio_end include/linux/delayacct.h:125 [inline] try_to_wake_up+0x107/0x470 kernel/sched/core.c:2892 autoremove_wake_function+0xc/0x50 kernel/sched/wait.c:389 __wake_up_common+0xbc/0x130 kernel/sched/wait.c:93 __wake_up_common_lock kernel/sched/wait.c:123 [inline] __wake_up+0x80/0xc0 kernel/sched/wait.c:142 __wake_up_bit kernel/sched/wait_bit.c:126 [inline] wake_up_bit+0x72/0x90 kernel/sched/wait_bit.c:149 unlock_buffer fs/buffer.c:77 [inline] __end_buffer_read_notouch fs/buffer.c:150 [inline] end_buffer_read_sync+0x64/0x70 fs/buffer.c:159 end_bio_bh_io_sync+0x6f/0x90 fs/buffer.c:3005 bio_endio+0x28b/0x350 block/bio.c:1450 req_bio_endio block/blk-core.c:263 [inline] blk_update_request+0x4d5/0xb00 block/blk-core.c:1467 blk_mq_end_request+0x22/0x50 block/blk-mq.c:562 lo_complete_rq+0xca/0x180 drivers/block/loop.c:501 blk_done_softirq+0x145/0x190 block/blk-mq.c:586 __do_softirq+0x12c/0x2b1 kernel/softirq.c:298 run_ksoftirqd+0x13/0x20 kernel/softirq.c:653 smpboot_thread_fn+0x34f/0x520 kernel/smpboot.c:165 kthread+0x1fa/0x220 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.10.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================