I have strange kernel panic Kernel 3.13.3 vanilla root is mounted via 9p virtfs (readonly). virsh --version 1.2.1 qemu --version QEMU emulator version 1.7.0, Copyright (c) 2003-2008 Fabrice Bellard systemd version 210 Domain config: <domain type='kvm'> <name>build</name> <uuid>328891df-b3c3-aee9-eb5d-00007e7934f7</uuid> <memory unit='MiB'>512</memory> <currentMemory unit='MiB'>512</currentMemory> <vcpu placement='static'>2</vcpu> <resource> <partition>/machine</partition> </resource> <os> <type arch='x86_64' machine='pc-1.0'>hvm</type> <boot dev='hd'/> <kernel>/boot/vmlinuz-3.13.3</kernel> <initrd>/boot/initrd-3.13.3</initrd> <cmdline>ro root=virtfs:root console=tty0 console=ttyS0,115200n8 </cmdline> </os> <features> <acpi/> <apic/> <pae/> </features> <clock offset='utc'/> <on_poweroff>destroy</on_poweroff> <on_reboot>destroy</on_reboot> <on_crash>destroy</on_crash> <devices> <emulator>/usr/bin/qemu-system-x86_64</emulator> <filesystem type='mount' accessmode='squash'> <driver type='path' wrpolicy='immediate'/> <source dir='/home/vtolstov/devel/vtolstov/lb/fs/x86_64'/> <target dir='root'/> <readonly/> </filesystem> <filesystem type='mount' accessmode='squash'> <driver type='path' wrpolicy='immediate'/> <source dir='/home/vtolstov/devel/vtolstov/lb/fs/var/log'/> <target dir='var/log'/> </filesystem> <filesystem type='mount' accessmode='squash'> <driver type='path' wrpolicy='immediate'/> <source dir='/home/vtolstov/devel/vtolstov/lb/fs/var/cache/paludis'/> <target dir='var/cache/paludis'/> </filesystem> <filesystem type='mount' accessmode='squash'> <driver type='path' wrpolicy='immediate'/> <source dir='/home/vtolstov/devel/vtolstov/lb/fs/var/db/paludis'/> <target dir='var/db/paludis'/> </filesystem> <controller type='virtio-serial' index='0'> <alias name='virtio-serial0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/> </controller> <controller type='pci' index='0' model='pci-root'> <alias name='pci0'/> </controller> <controller type='ide' index='0'> <alias name='ide0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/> </controller> <interface type='network'> <mac address='52:54:00:00:02:4c'/> <source network='mighost'/> <model type='virtio'/> <alias name='net0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> </interface> <serial type='pty'> <source path='/dev/pts/8'/> <target port='0'/> <alias name='serial0'/> </serial> <console type='pty' tty='/dev/pts/8'> <source path='/dev/pts/8'/> <target type='serial' port='0'/> <alias name='serial0'/> </console> <channel type='spicevmc'> <target type='virtio' name='com.redhat.spice.0'/> <alias name='channel0'/> <address type='virtio-serial' controller='0' bus='0' port='1'/> </channel> <channel type='unix'> <source mode='bind' path='/var/lib/libvirt/qemu/build.agent'/> <target type='virtio' name='org.mighost.agent.0'/> <alias name='channel1'/> <address type='virtio-serial' controller='0' bus='0' port='2'/> </channel> <input type='mouse' bus='ps2'/> <graphics type='vnc' port='5905' autoport='yes' listen='0.0.0.0'> <listen type='address' address='0.0.0.0'/> </graphics> <video> <model type='vga' vram='9216' heads='1'/> <alias name='video0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/> </video> <memballoon model='virtio'> <alias name='balloon0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/> </memballoon> </devices> <seclabel type='none'/> </domain> Sometimes i get error like: [ OK ] Reached target Initrd File Systems. Starting dracut mount hook... [ 14.326081] FDC 0 is a S82078B [ 14.644148] PANIC: double fault, error_code: 0x0 [ 14.640174] PANIC: double fault, error_code: 0x0 [ 14.640174] CPU: 0 PID: 130 Comm: systemd-udevd Not tainted 3.13.3 #2 [ 14.640174] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 14.640174] task: ffff88001faf0000 ti: ffff88001faee000 task.ti: ffff88001faee000 [ 14.640174] RIP: 0010:[<ffffffff81109df8>] [<ffffffff81109df8>] file_read_actor+0x58/0x160 [ 14.640174] RSP: 0018:ffff88001faefd60 EFLAGS: 00010206 [ 14.640174] RAX: 0000000000000000 RBX: ffff88001faefe10 RCX: 000000000000100f [ 14.640174] RDX: 0000000000000000 RSI: ffffea000070ebc0 RDI: 00007f94d60b3037 [ 14.640174] RBP: ffff88001faefd90 R08: 0000000000000002 R09: ffffea000070ebdc [ 14.640174] R10: 0000000000000023 R11: 0000000000000000 R12: 0000000000001000 [ 14.640174] R13: 000000000001f000 R14: ffff88001f9d5e00 R15: 0000000000001000 [ 14.640174] FS: 00007f94d60dc7c0(0000) GS:ffff88001f400000(0000) knlGS:0000000000000000 [ 14.640174] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 14.640174] CR2: 0000000000000000 CR3: 000000001fad9000 CR4: 00000000000006f0 [ 14.640174] Stack: [ 14.640174] ffff88001faefd70 ffff88001e025280 0000000000000021 0000000000001000 [ 14.640174] ffff88001f9d5e00 ffffea000070ebc0 ffff88001faefe58 ffffffff8110a1ca [ 14.640174] ffff88001f9d5e10 ffff88001faefe90 ffff88001faefea0 0000000000000000 [ 14.640174] Call Trace: [ 14.640174] [<ffffffff8110a1ca>] generic_file_aio_read+0x2ca/0x700 [ 14.640174] [<ffffffff811a11f6>] blkdev_aio_read+0x46/0x70 [ 14.640174] [<ffffffff8116c355>] do_sync_read+0x55/0x90 [ 14.640174] [<ffffffff8116c9e0>] vfs_read+0x90/0x160 [ 14.640174] [<ffffffff8116d4e4>] SyS_read+0x44/0xa0 [ 14.640174] [<ffffffff816ab07d>] system_call_fastpath+0x1a/0x1f [ 14.640174] Code: 38 31 c0 66 66 90 c6 01 00 66 66 90 85 c0 0f 85 bf 00 00 00 49 63 fc 48 8d 7c 39 ff 48 31 f9 48 f7 c1 00 f0 ff ff 74 11 66 66 90 <c6> 07 00 66 66 90 85 c0 0f 85 c6 00 00 00 65 ff 04 25 e0 c7 00 [ 14.640174] Kernel panic - not syncing: Machine halted. [ 14.644148] CPU: 1 PID: 126 Comm: systemd-udevd Not tainted 3.13.3 #2 [ 14.644148] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 14.644148] task: ffff88001fa42f80 ti: ffff88001fa84000 task.ti: ffff88001fa84000 [ 14.644148] RIP: 0010:[<ffffffff81109df8>] [<ffffffff81109df8>] file_read_actor+0x58/0x160 [ 14.644148] RSP: 0018:ffff88001fa85d60 EFLAGS: 00010206 [ 14.644148] RAX: 0000000000000000 RBX: ffff88001fa85e10 RCX: 000000000000100f [ 14.644148] RDX: 0000000000000000 RSI: ffffea0000708340 RDI: 00007f94d60cb037 [ 14.644148] RBP: ffff88001fa85d90 R08: 0000000000000002 R09: ffffea000070835c [ 14.644148] R10: 000000000000003b R11: 0000000000000001 R12: 0000000000001000 [ 14.644148] R13: 0000000000007000 R14: ffff88001f9d3900 R15: 0000000000001000 [ 14.640174] Shutting down cpus with NMI [ 14.644148] FS: 00007f94d60dc7c0(0000) GS:ffff88001f500000(0000) knlGS:0000000000000000 [ 14.644148] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 14.644148] CR2: 0000000000000000 CR3: 000000001fa67000 CR4: 00000000000006e0 [ 14.644148] Stack: [ 14.644148] ffff88001fa85d70 ffff88001e2522c0 0000000000000039 0000000000001000 [ 14.644148] ffff88001f9d3900 ffffea0000708340 ffff88001fa85e58 ffffffff8110a1ca [ 14.644148] ffff88001f9d3910 ffff88001fa85e90 ffff88001fa85ea0 0000000000000000 [ 14.644148] Call Trace: [ 14.644148] [<ffffffff8110a1ca>] generic_file_aio_read+0x2ca/0x700 [ 14.644148] [<ffffffff811a11f6>] blkdev_aio_read+0x46/0x70 [ 14.644148] [<ffffffff8116c355>] do_sync_read+0x55/0x90 [ 14.644148] [<ffffffff8116c9e0>] vfs_read+0x90/0x160 [ 14.644148] [<ffffffff8116d4e4>] SyS_read+0x44/0xa0 [ 14.644148] [<ffffffff816ab07d>] system_call_fastpath+0x1a/0x1f [ 14.644148] Code: 38 31 c0 66 66 90 c6 01 00 66 66 90 85 c0 0f 85 bf 00 00 00 49 63 fc 48 8d 7c 39 ff 48 31 f9 48 f7 c1 00 f0 ff ff 74 11 66 66 90 <c6> 07 00 66 66 90 85 c0 0f 85 c6 00 00 00 65 ff 04 25 e0 c7 00 -- Vasiliy Tolstov, e-mail: v.tolstov(a)selfip.ru jabber: vase(a)selfip.ru