WARNING: CPU: 1 PID: 13341 at kernel/fork.c:672 __mmdrop+0x25e/0x320 kernel/fork.c:672 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 13341 Comm: syz-executor.0 Not tainted 5.2.0-rc3-next-20190607 #11 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 panic+0x2cb/0x744 kernel/panic.c:219 __warn.cold+0x20/0x4d kernel/panic.c:576 report_bug+0x263/0x2b0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:179 [inline] fixup_bug arch/x86/kernel/traps.c:174 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:291 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:986 RIP: 0010:__mmdrop+0x25e/0x320 kernel/fork.c:672 Code: f8 5c 67 00 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 38 a7 2e 00 4c 89 ef e8 20 02 2b 00 eb d2 e8 29 a7 2e 00 0f 0b e8 22 a7 2e 00 <0f> 0b e9 fa fd ff ff e8 16 a7 2e 00 0f 0b e9 2b fe ff ff e8 0a a7 RSP: 0018:ffff8880583bfa80 EFLAGS: 00010202 RAX: ffff88805c288680 RBX: ffff88805c288680 RCX: ffffffff81a81165 RDX: 0000000000000003 RSI: ffffffff8142369e RDI: ffff88805c288aa8 RBP: ffff8880583bfaa8 R08: 0000000000200000 R09: 00000000000079fc R10: 00000000000f3f88 R11: 000000000001e7ec R12: ffff8880907b2f00 R13: ffff8880907b2f5c R14: ffff88805a2e1a50 R15: 0000000000000002 mmdrop include/linux/sched/mm.h:49 [inline] mmu_notifier_unregister+0x368/0x440 mm/mmu_notifier.c:376 vhost_dev_cleanup+0x82b/0xc60 drivers/vhost/vhost.c:963 vhost_vsock_dev_release+0x324/0x470 drivers/vhost/vsock.c:628 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 get_signal+0x2007/0x2490 kernel/signal.c:2522 do_signal+0x87/0x1990 arch/x86/kernel/signal.c:815 exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x58e/0x680 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459279 Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f260e2f7c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: fffffffffffffff2 RBX: 0000000000000003 RCX: 0000000000459279 RDX: 00000000200003c0 RSI: 000000004004af61 RDI: 0000000000000003 RBP: 000000000075c100 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f260e2f86d4 R13: 00000000004c41bb R14: 00000000004d7e48 R15: 00000000ffffffff Kernel Offset: disabled Rebooting in 86400 seconds..