I see kernel 3.15 is now out, so I retested with 3.15 guest and host. I'm still getting exactly the same guest kernel panic: a divide error in kvm_unlock_kick with -cpu host, but not with -cpu qemu64: divide error: 0000 [#1] PREEMPT SMP Modules linked in: CPU: 1 PID: 781 Comm: mkdir Not tainted 3.15.0-guest #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS Bochs 01/01/2011 task: ffff88007cbf6180 ti: ffff880000088000 task.ti: ffff880000088000 RIP: 0010:[<ffffffff8102d1e0>] [<ffffffff8102d1e0>] kvm_unlock_kick+0x63/0x6b RSP: 0000:ffff88007fc83d38 EFLAGS: 00010046 RAX: 0000000000000005 RBX: 0000000000000000 RCX: 0000000000000002 RDX: 0000000000000002 RSI: ffff88007fd11d80 RDI: ffffffff81994840 RBP: ffff88007fd11d80 R08: 0000000000000000 R09: ffffffff81994840 R10: ffff88007c480c88 R11: 0000000000000005 R12: 000000000000cec0 R13: ffff88007d38332a R14: 0000000000000002 R15: ffff88007d382d00 FS: 00007fdabf7fd700(0000) GS:ffff88007fc80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd0643f6509 CR3: 000000007c028000 CR4: 00000000000406e0 Stack: 0000000000011d80 0000000000000002 ffff88007fd11d80 ffffffff8156f83f ffffffff810dba53 0000000000000046 ffff88007fd00000 ffff88007d3bbe70 ffffffff81845da8 0000000000000003 0000000000000000 0000000000000000 Call Trace: <IRQ> [<ffffffff8156f83f>] ? _raw_spin_unlock+0x32/0x55 [<ffffffff810dba53>] ? try_to_wake_up+0x1ed/0x20f [<ffffffff810e78b8>] ? autoremove_wake_function+0x9/0x2a [<ffffffff810e739a>] ? __wake_up_common+0x47/0x73 [<ffffffff810e7547>] ? __wake_up+0x33/0x44 [<ffffffff8110f10b>] ? irq_work_run+0x72/0x8f [<ffffffff81006079>] ? smp_irq_work_interrupt+0x26/0x2b [<ffffffff8157185d>] ? irq_work_interrupt+0x6d/0x80 [<ffffffff810dba64>] ? try_to_wake_up+0x1fe/0x20f [<ffffffff8102ad01>] ? native_apic_msr_read+0x6/0x4e [<ffffffff8156f89f>] ? _raw_spin_unlock_irqrestore+0x3d/0x65 [<ffffffff810f2de3>] ? rcu_process_callbacks+0x15e/0x47d [<ffffffff810cccf3>] ? execute_in_process_context+0x55/0x55 [<ffffffff810bdb98>] ? __do_softirq+0xe0/0x1e6 [<ffffffff810bde23>] ? irq_exit+0x3c/0x81 [<ffffffff810270e4>] ? smp_apic_timer_interrupt+0x3b/0x46 [<ffffffff8157135d>] ? apic_timer_interrupt+0x6d/0x80 <EOI> Code: 0c c5 c0 b8 87 81 49 8d 04 0c 48 8b 30 48 39 ee 75 ca 8a 40 08 38 d8 75 c3 48 c7 c0 22 b0 00 00 31 db 0f b7 0c 08 b8 05 00 00 00 <0f> 01 c1 5b 5d 41 5c c3 4c 8d 54 24 08 48 83 e4 f0 b9 0a 00 00 RIP [<ffffffff8102d1e0>] kvm_unlock_kick+0x63/0x6b RSP <ffff88007fc83d38> ---[ end trace 949b1bf47cc57d09 ]--- Kernel panic - not syncing: Fatal exception in interrupt Shutting down cpus with NMI Kernel Offset: 0x0 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffff9fffffff) ---[ end Kernel panic - not syncing: Fatal exception in interrupt I'm at a complete loss as to what to do next to debug this. Any help would be extremely gratefully received! I've put 3.15 host and guest configs here: http://cdw.me.uk/tmp/3.15-guest-config.txt http://cdw.me.uk/tmp/3.15-host-config.txt dmesg just after boot here: http://cdw.me.uk/tmp/3.15-guest-dmesg.txt http://cdw.me.uk/tmp/3.15-host-dmesg.txt and /proc/cpuinfo from both host and guest here: http://cdw.me.uk/tmp/3.15-guest-cpuinfo.txt http://cdw.me.uk/tmp/3.15-host-cpuinfo.txt The qemu command line was qemu-system-x86 -enable-kvm -cpu host -machine q35 -m 2048 -name omega \ -smp sockets=1,cores=4 -pidfile /run/omega.pid -runas nobody \ -serial stdio -vga none -vnc none -kernel /boot/vmlinuz-guest \ -append "console=ttyS0 root=/dev/vda" \ -drive file=/dev/guest/omega,cache=none,format=raw,if=virtio \ -device virtio-rng-pci \ -device virtio-net-pci,netdev=nic,mac=02:14:72:3c:69:54 \ -netdev tap,id=nic,fd=3,vhost=on 3<>/dev/tapNNN but removing the -machine q35 and -device virtio-rng-pci doesn't affect the crash. Dropping to -smp 1, running with -cpu qemu64, or compiling the guest kernel without paravirtualised spinlock support does remove the panic, albeit at the cost of performance. Best wishes, Chris. _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
