workqueue: Failed to create a rescuer kthread for wq "kcopyd": -EINTR ================================================================== BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:82 [inline] BUG: KASAN: null-ptr-deref in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] BUG: KASAN: null-ptr-deref in dm_kcopyd_client_destroy+0xae/0x480 drivers/md/dm-kcopyd.c:980 Read of size 4 at addr 0000000000000174 by task syz.0.0/5356 CPU: 0 UID: 0 PID: 5356 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 kasan_report+0x117/0x150 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x264/0x2c0 mm/kasan/generic.c:200 instrument_atomic_read include/linux/instrumented.h:82 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] dm_kcopyd_client_destroy+0xae/0x480 drivers/md/dm-kcopyd.c:980 __destroy+0x172/0x2f0 drivers/md/dm-cache-target.c:1973 cache_create drivers/md/dm-cache-target.c:2604 [inline] cache_ctr+0x1674/0x2bf0 drivers/md/dm-cache-target.c:2649 dm_table_add_target+0x58d/0xc70 drivers/md/dm-table.c:749 populate_table drivers/md/dm-ioctl.c:1602 [inline] table_load+0x325/0x8a0 drivers/md/dm-ioctl.c:1645 ctl_ioctl drivers/md/dm-ioctl.c:2221 [inline] dm_ctl_ioctl+0x9ec/0xe10 drivers/md/dm-ioctl.c:2243 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd6cdb9f559 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd6c9fd3fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fd6cde26270 RCX: 00007fd6cdb9f559 RDX: 00002000000005c0 RSI: 00000000c138fd09 RDI: 0000000000000005 RBP: 00007fd6cdc36b20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd6cde26308 R14: 00007fd6cde26270 R15: 00007fff20db9288 ==================================================================