watchdog: BUG: soft lockup - CPU#1 stuck for 123s! [syz-executor.4:442] Modules linked in: irq event stamp: 10991676 hardirqs last enabled at (10991675): [] trace_hardirqs_on_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:41 hardirqs last disabled at (10991676): [] trace_hardirqs_off_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:42 softirqs last enabled at (10991674): [] __do_softirq+0x673/0x950 kernel/softirq.c:319 softirqs last disabled at (10991667): [] invoke_softirq kernel/softirq.c:373 [inline] softirqs last disabled at (10991667): [] irq_exit+0x178/0x1a0 kernel/softirq.c:413 CPU: 1 PID: 442 Comm: syz-executor.4 Not tainted 5.6.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline] RIP: 0010:csd_lock_wait kernel/smp.c:109 [inline] RIP: 0010:smp_call_function_single+0x2cf/0x3a0 kernel/smp.c:311 Code: 5f 5d c3 e8 53 62 0a 00 48 8b 54 24 08 4c 89 f9 8b 7c 24 14 48 8d 74 24 40 e8 cd f9 ff ff 41 89 c4 eb 07 e8 33 62 0a 00 f3 90 <8b> 5c 24 58 31 ff 83 e3 01 89 de e8 c1 63 0a 00 85 db 75 e5 e8 18 RSP: 0018:ffff8881ab86f7a0 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13 RAX: ffff8881ab859880 RBX: 0000000000000001 RCX: ffffffff8134f3bf RDX: 0000000000000000 RSI: ffffffff8134f3ad RDI: 0000000000000005 RBP: ffff8881ab86f880 R08: ffff8881ab859880 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000001 R14: ffff8881d27ec040 R15: ffff8881db333e00 FS: 0000000000000000(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c42017dc80 CR3: 0000000007021000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: smp_call_function_many_cond+0x25e/0x900 kernel/smp.c:439 flush_tlb_others arch/x86/include/asm/paravirt.h:68 [inline] flush_tlb_mm_range+0x1e8/0x3e0 arch/x86/mm/tlb.c:798 tlb_flush arch/x86/include/asm/tlb.h:24 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:424 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:414 [inline] tlb_flush_mmu+0x274/0x630 mm/mmu_gather.c:248 tlb_finish_mmu+0x93/0x420 mm/mmu_gather.c:328 exit_mmap+0x298/0x4d0 mm/mmap.c:3128 __mmput kernel/fork.c:1082 [inline] mmput+0xce/0x3d0 kernel/fork.c:1103 exit_mm kernel/exit.c:485 [inline] do_exit+0xa83/0x2c80 kernel/exit.c:788 do_group_exit+0x125/0x340 kernel/exit.c:899 get_signal+0x480/0x2470 kernel/signal.c:2739 do_signal+0x88/0x1490 arch/x86/kernel/signal.c:813 exit_to_usermode_loop+0x1a2/0x200 arch/x86/entry/common.c:160 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_64+0x4e0/0x5a0 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45acf0 Code: Bad RIP value. RSP: 002b:00007ffd95eeeb38 EFLAGS: 00000246 ORIG_RAX: 0000000000000023 RAX: fffffffffffffdfc RBX: 00000000000800c8 RCX: 000000000045acf0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007ffd95eeeb40 RBP: 0000000000000299 R08: 0000000000000001 R09: 000000000128c940 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd95eeeb90 R14: 00000000000800c8 R15: 00007ffd95eeeba0 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.6.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:line6_midibuf_read+0x52f/0xa30 sound/usb/line6/midibuf.c:228 Code: 85 17 04 00 00 48 8b 44 24 10 88 18 e8 2a f7 84 fc 48 8d 7d 18 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 <84> c0 74 08 3c 03 0f 8e 61 04 00 00 c7 45 18 00 00 00 00 e8 f9 f6 RSP: 0018:ffff8881db2099e0 EFLAGS: 00000806 RAX: 0000000000000000 RBX: 00000000000000fb RCX: ffffc90000022000 RDX: 1ffff1103964e117 RSI: ffffffff84ba5eb6 RDI: ffff8881cb2708b8 RBP: ffff8881cb2708a0 R08: ffffffff8702cc40 R09: ffffed103964e241 R10: ffffed103964e240 R11: ffff8881cb271200 R12: 0000000000000001 R13: 0000000000000014 R14: 00000000000003ec R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8881db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000748000 CR3: 00000001ab844000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: line6_data_received+0x318/0x520 sound/usb/line6/driver.c:305 __usb_hcd_giveback_urb+0x29a/0x550 drivers/usb/core/hcd.c:1650 usb_hcd_giveback_urb+0x368/0x420 drivers/usb/core/hcd.c:1716 dummy_timer+0x1258/0x32ae drivers/usb/gadget/udc/dummy_hcd.c:1966 call_timer_fn+0x195/0x6f0 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0x5f9/0x1500 kernel/time/timer.c:1786 __do_softirq+0x21e/0x950 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x178/0x1a0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:546 [inline] smp_apic_timer_interrupt+0x141/0x540 arch/x86/kernel/apic/apic.c:1146 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:default_idle+0x28/0x300 arch/x86/kernel/process.c:696 Code: cc cc 41 56 41 55 65 44 8b 2d 44 77 72 7a 41 54 55 53 0f 1f 44 00 00 e8 b6 62 b5 fb e9 07 00 00 00 0f 00 2d ea 0c 53 00 fb f4 <65> 44 8b 2d 20 77 72 7a 0f 1f 44 00 00 5b 5d 41 5c 41 5d 41 5e c3 RSP: 0018:ffffffff87007d80 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000007 RBX: ffffffff8702cc40 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000006 RDI: ffffffff8702d48c RBP: fffffbfff0e05988 R08: ffffffff8702cc40 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff87e607c0 R15: 0000000000000000 cpuidle_idle_call kernel/sched/idle.c:154 [inline] do_idle+0x3e0/0x500 kernel/sched/idle.c:269 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:361 start_kernel+0xe16/0xe5a init/main.c:998 secondary_startup_64+0xb6/0xc0 arch/x86/kernel/head_64.S:242