watchdog: BUG: soft lockup - CPU#0 stuck for 31s! [syz-executor.1:24476] Modules linked in: irq event stamp: 52229231 hardirqs last enabled at (52229230): [] restore_regs_and_return_to_kernel+0x0/0x2a hardirqs last disabled at (52229231): [] apic_timer_interrupt+0x8e/0xa0 arch/x86/entry/entry_64.S:793 softirqs last enabled at (9196): [] __do_softirq+0x68b/0x9ff kernel/softirq.c:314 softirqs last disabled at (52229227): [] invoke_softirq kernel/softirq.c:368 [inline] softirqs last disabled at (52229227): [] irq_exit+0x193/0x240 kernel/softirq.c:409 CPU: 0 PID: 24476 Comm: syz-executor.1 Not tainted 4.14.232-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff88803e84a580 task.stack: ffff8880b4b70000 RIP: 0010:ffs arch/x86/include/asm/bitops.h:427 [inline] RIP: 0010:__do_softirq+0x215/0x9ff kernel/softirq.c:276 RSP: 0018:ffff8880ba407f30 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff10 RAX: 1ffffffff11e125b RBX: ffff88803e84a580 RCX: 1ffff11007d095c5 RDX: 0000000000000000 RSI: ffff88803e84ae08 RDI: ffff88803e84ae04 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 00000000000000b1 R13: 00000000000000b1 R14: 0000000000000000 R15: dffffc0000000000 FS: 00007f83ef979700(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000092d3f000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: invoke_softirq kernel/softirq.c:368 [inline] irq_exit+0x193/0x240 kernel/softirq.c:409 exiting_irq arch/x86/include/asm/apic.h:638 [inline] do_IRQ+0x112/0x1d0 arch/x86/kernel/irq.c:242 common_interrupt+0x93/0x93 arch/x86/entry/entry_64.S:576 RIP: 0010:__srcu_read_lock+0x6e/0x90 kernel/rcu/srcutree.c:383 RSP: 0018:ffff8880b4b77ad8 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff4e RAX: 0000000000000001 RBX: ffff8880465d81e0 RCX: 0000000000000001 RDX: 0000607f4589d8c0 RSI: 00000000ffffffff RDI: ffff8880465d83e0 RBP: ffff8880b4b77c40 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: ffff88803e84a580 R12: 0000000000000001 R13: ffff8880465d8568 R14: dffffc0000000000 R15: ffff88809eee0f00 srcu_read_lock include/linux/srcu.h:159 [inline] vcpu_run arch/x86/kvm/x86.c:7395 [inline] kvm_arch_vcpu_ioctl_run+0x13b4/0x5ae0 arch/x86/kvm/x86.c:7531 kvm_vcpu_ioctl+0x3de/0xc50 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2661 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x4665f9 RSP: 002b:00007f83ef979188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005 RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffc9e064fbf R14: 00007f83ef979300 R15: 0000000000022000 Code: 48 c7 c0 d8 92 f0 88 48 c1 e8 03 42 80 3c 38 00 0f 85 38 07 00 00 48 83 3d d0 90 90 01 00 0f 84 8e 06 00 00 fb 66 0f 1f 44 00 00 ff ff ff ff 48 c7 c3 c0 90 e0 88 0f bc 44 24 04 89 c6 83 c6 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 22 Comm: kworker/u4:1 Not tainted 4.14.232-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-8:0) task: ffff8880b55ec5c0 task.stack: ffff8880b55f8000 RIP: 0010:__read_once_size include/linux/compiler.h:183 [inline] RIP: 0010:csd_lock_wait kernel/smp.c:108 [inline] RIP: 0010:smp_call_function_single+0x181/0x370 kernel/smp.c:302 RSP: 0018:ffff8880b55feea0 EFLAGS: 00000297 RAX: ffff8880b55ec5c0 RBX: 1ffff11016abfdd8 RCX: 1ffff11016abd9e6 RDX: 0000000000000000 RSI: ffff8880b55ecf10 RDI: 0000000000000286 RBP: ffff8880b55fef50 R08: ffffffff8b994620 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff8880b55ff008 R14: 0000000000000001 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000541198 CR3: 0000000008e6a000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: smp_call_function_many+0x60f/0x7a0 kernel/smp.c:434 flush_tlb_others arch/x86/include/asm/paravirt.h:309 [inline] flush_tlb_mm_range+0x158/0x2f0 arch/x86/mm/tlb.c:709 flush_tlb_page arch/x86/include/asm/tlbflush.h:573 [inline] ptep_clear_flush+0xde/0x110 mm/pgtable-generic.c:87 page_mkclean_one+0x237/0x540 mm/rmap.c:915 rmap_walk_file+0x37c/0x810 mm/rmap.c:1829 rmap_walk+0xc4/0x150 mm/rmap.c:1847 page_mkclean+0x148/0x180 mm/rmap.c:981 clear_page_dirty_for_io+0x1a6/0xb80 mm/page-writeback.c:2704 mpage_submit_page+0x6e/0x220 fs/ext4/inode.c:2214 mpage_process_page_bufs+0x425/0x520 fs/ext4/inode.c:2344 mpage_prepare_extent_to_map+0x43e/0xa10 fs/ext4/inode.c:2716 ext4_writepages+0xf88/0x32a0 fs/ext4/inode.c:2863 do_writepages+0xc3/0x240 mm/page-writeback.c:2361 __writeback_single_inode+0xda/0x1010 fs/fs-writeback.c:1377 writeback_sb_inodes+0x48b/0xd30 fs/fs-writeback.c:1639 __writeback_inodes_wb+0xbf/0x230 fs/fs-writeback.c:1708 wb_writeback+0x710/0xb80 fs/fs-writeback.c:1814 wb_check_old_data_flush fs/fs-writeback.c:1927 [inline] wb_do_writeback fs/fs-writeback.c:1951 [inline] wb_workfn+0x708/0xf50 fs/fs-writeback.c:1980 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Code: c3 08 00 48 8b 54 24 10 4c 89 e9 8b 7c 24 1c 48 8d 74 24 40 e8 71 fa ff ff 41 89 c4 8b 44 24 58 a8 01 74 0f e8 e1 c2 08 00 f3 90 <8b> 44 24 58 a8 01 75 f1 e8 d2 c2 08 00 e8 cd c2 08 00 bf 01 00