syz-executor280[10257]: segfault at 0 ip 0000000000000000 sp 0000000020000008 error 14 Code: Bad RIP value. syz-executor280[10263]: segfault at 0 ip 0000000000000000 sp 0000000020000008 error 14 Code: Bad RIP value. INFO: task kworker/u4:2:8317 blocked for more than 140 seconds. Not tainted 4.19.211-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:2 D26864 8317 2 0x80000000 Workqueue: writeback wb_workfn (flush-7:0) Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1016 [inline] __mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078 f2fs_balance_fs+0x709/0xd80 fs/f2fs/segment.c:512 f2fs_write_inode+0x500/0x600 fs/f2fs/inode.c:630 write_inode fs/fs-writeback.c:1244 [inline] __writeback_single_inode+0x733/0x11d0 fs/fs-writeback.c:1442 writeback_sb_inodes+0x537/0xef0 fs/fs-writeback.c:1647 __writeback_inodes_wb+0xc6/0x280 fs/fs-writeback.c:1716 wb_writeback+0x841/0xcc0 fs/fs-writeback.c:1822 wb_check_old_data_flush fs/fs-writeback.c:1924 [inline] wb_do_writeback fs/fs-writeback.c:1977 [inline] wb_workfn+0x8ba/0x1250 fs/fs-writeback.c:2006 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Showing all locks held in the system: 1 lock held by khungtaskd/1571: #0: 00000000829e72c7 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7853: #0: 000000009f998f2f (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 3 locks held by syz-executor280/8149: 4 locks held by kworker/u4:2/8317: #0: 00000000b3c347d9 ((wq_completion)"writeback"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 000000002299b0b2 ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 #2: 000000003d610b4d (&type->s_umount_key#47){.+.+}, at: trylock_super+0x1d/0x100 fs/super.c:412 #3: 00000000c0721fe5 (&sbi->gc_mutex){+.+.}, at: f2fs_balance_fs+0x709/0xd80 fs/f2fs/segment.c:512 2 locks held by syz-executor280/10264: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1571 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 10263 Comm: syz-executor280 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50 kernel/kcov.c:97 Code: ff 48 89 df e8 11 dd 35 00 e9 ab fe ff ff 4c 89 ef e8 04 dd 35 00 e9 23 fe ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <48> 8b 34 24 65 48 8b 04 25 c0 df 01 00 65 8b 15 cc 59 9f 7e 81 e2 RSP: 0018:ffff8880ba107af8 EFLAGS: 00000002 RAX: 0000000080010004 RBX: 0000000000010004 RCX: ffffffff83771e23 RDX: 0000000000010004 RSI: ffff88809c676000 RDI: 0000000000000005 RBP: ffffffff88b3e120 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000005 R11: ffffffff8c66505b R12: 0000000000000001 R13: ffffffff88b3e0e0 R14: 000000000001e728 R15: ffff8880b028a640 FS: 0000000000000000(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3e96e00000 CR3: 00000000aad53000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: check_preemption_disabled+0x3c/0x280 lib/smp_processor_id.c:25 rcu_lockdep_current_cpu_online kernel/rcu/tree.c:1078 [inline] rcu_lockdep_current_cpu_online+0xb2/0x1b0 kernel/rcu/tree.c:1068 rcu_read_lock_held+0xc3/0x110 kernel/rcu/update.c:285 test_idle_cores kernel/sched/fair.c:6041 [inline] select_idle_core kernel/sched/fair.c:6090 [inline] select_idle_sibling kernel/sched/fair.c:6241 [inline] select_idle_sibling+0x1b1/0xae0 kernel/sched/fair.c:6208 select_task_rq_fair+0x6df/0x2750 kernel/sched/fair.c:6479 select_task_rq kernel/sched/core.c:1532 [inline] try_to_wake_up+0x4cd/0x1050 kernel/sched/core.c:2037 hrtimer_wakeup+0x43/0x60 kernel/time/hrtimer.c:1713 __run_hrtimer kernel/time/hrtimer.c:1465 [inline] __hrtimer_run_queues+0x3f6/0xe60 kernel/time/hrtimer.c:1527 hrtimer_interrupt+0x326/0x9e0 kernel/time/hrtimer.c:1585 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1071 [inline] smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1096 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:789 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa3/0xe0 kernel/locking/spinlock.c:184 Code: 48 c7 c0 88 82 f1 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 2f 48 83 3d 7c 31 d8 01 00 74 15 48 89 df 57 9d <0f> 1f 44 00 00 eb b2 e8 fb eb e6 f8 eb c0 0f 0b 0f 0b 48 c7 c7 88 RSP: 0018:ffff8880aa756a48 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff13e3051 RBX: 0000000000000286 RCX: 1ffff110138ced15 RDX: dffffc0000000000 RSI: ffff88809c6768b0 RDI: 0000000000000286 RBP: ffff8880ad843bb0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000286 R14: 000000000000006c R15: ffff8880ad843be8 spin_unlock_irqrestore include/linux/spinlock.h:384 [inline] virtscsi_kick_cmd+0xbd/0x120 drivers/scsi/virtio_scsi.c:478 virtscsi_queuecommand+0x6af/0xf70 drivers/scsi/virtio_scsi.c:569 scsi_dispatch_cmd+0x394/0xc00 drivers/scsi/scsi_lib.c:1837 scsi_queue_rq+0x1477/0x1aa0 drivers/scsi/scsi_lib.c:2140 blk_mq_dispatch_rq_list+0xca7/0x1980 block/blk-mq.c:1203 blk_mq_do_dispatch_sched+0x187/0x400 block/blk-mq-sched.c:117 blk_mq_sched_dispatch_requests+0x38c/0x5b0 block/blk-mq-sched.c:213 __blk_mq_run_hw_queue+0x185/0x290 block/blk-mq.c:1324 __blk_mq_delay_run_hw_queue+0x4d8/0x5a0 block/blk-mq.c:1392 blk_mq_run_hw_queue+0x16b/0x2f0 block/blk-mq.c:1429 blk_mq_sched_insert_requests+0x203/0x2d0 block/blk-mq-sched.c:432 blk_mq_flush_plug_list+0x6a6/0xb00 block/blk-mq.c:1679 blk_flush_plug_list+0x2fb/0x8e0 block/blk-core.c:3705 blk_mq_make_request+0xf10/0x1c00 block/blk-mq.c:1908 generic_make_request+0x613/0xdf0 block/blk-core.c:2467 submit_bio+0xb1/0x430 block/blk-core.c:2576 ext4_io_submit+0x181/0x210 fs/ext4/page-io.c:356 ext4_writepages+0x17bf/0x37f0 fs/ext4/inode.c:2910 do_writepages+0xe5/0x290 mm/page-writeback.c:2344 __filemap_fdatawrite_range+0x27d/0x350 mm/filemap.c:446 ext4_alloc_da_blocks+0x207/0x360 fs/ext4/inode.c:3273 ext4_release_file+0x1ed/0x340 fs/ext4/file.c:89 __fput+0x2ce/0x890 fs/file_table.c:278 task_work_run+0x148/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xbf3/0x2be0 kernel/exit.c:870 do_group_exit+0x125/0x310 kernel/exit.c:967 get_signal+0x3f2/0x1f70 kernel/signal.c:2589 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:799 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163 prepare_exit_to_usermode+0x277/0x2d0 arch/x86/entry/common.c:198 retint_user+0x8/0x18 RIP: 0033: (null) Code: Bad RIP value. RSP: 002b:0000000020000008 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007f3e9b3a0599 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000080000 RBP: 00007ffdab407ed0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000000f4240 R13: 00007ffdab407ec0 R14: 00007ffdab407eb0 R15: 0000000000000003 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.101 msecs