================================================================== BUG: KCSAN: data-race in _prb_read_valid / prb_reserve write to 0xffffffff86ac8578 of 8 bytes by interrupt on cpu 0: prb_reserve+0x769/0xbb0 kernel/printk/printk_ringbuffer.c:1541 log_store kernel/printk/printk.c:506 [inline] log_output kernel/printk/printk.c:1935 [inline] vprintk_store+0x3c1/0x620 kernel/printk/printk.c:1986 vprintk_emit+0xd6/0x370 kernel/printk/printk.c:2011 dev_vprintk_emit+0x1c6/0x1ea drivers/base/core.c:4128 dev_printk_emit+0x6a/0x8c drivers/base/core.c:4139 __dev_printk+0xfa/0x103 drivers/base/core.c:4151 dev_printk+0x73/0x9b drivers/base/core.c:4168 scsi_print_command+0x4dc/0x560 drivers/scsi/scsi_logging.c:221 scsi_io_completion_action drivers/scsi/scsi_lib.c:820 [inline] scsi_io_completion+0xee7/0xfb0 drivers/scsi/scsi_lib.c:984 scsi_finish_command+0x26c/0x2b0 drivers/scsi/scsi.c:214 scsi_softirq_done+0xdf/0x440 drivers/scsi/scsi_lib.c:1443 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 read to 0xffffffff86ac8578 of 8 bytes by task 8002 on cpu 1: desc_read kernel/printk/printk_ringbuffer.c:480 [inline] desc_read_finalized_seq kernel/printk/printk_ringbuffer.c:1756 [inline] prb_read kernel/printk/printk_ringbuffer.c:1804 [inline] _prb_read_valid+0x1c9/0x8f0 kernel/printk/printk_ringbuffer.c:1884 prb_read_valid+0x39/0x60 kernel/printk/printk_ringbuffer.c:1933 do_syslog+0xe18/0x1400 kernel/printk/printk.c:1611 kmsg_read+0x7a/0xa0 fs/proc/kmsg.c:40 pde_read fs/proc/inode.c:321 [inline] proc_reg_read+0xe1/0x1b0 fs/proc/inode.c:331 vfs_read+0x154/0x5c0 fs/read_write.c:494 ksys_read+0xce/0x180 fs/read_write.c:634 __do_sys_read fs/read_write.c:644 [inline] __se_sys_read fs/read_write.c:642 [inline] __x64_sys_read+0x3e/0x50 fs/read_write.c:642 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 8002 Comm: in:imklog Not tainted 5.10.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================