qemu, kernel breaks

Message

akam · Post by **akam** » Tue Mar 15, 2011 8:18 pm

hello, in a few weeks my virtual machine server (qemu+libvirt) regularly breaks down with such a record in the logs:

Mar 15 17:58:04 mainhost kernel: [65866.976982] BUG: unable to handle kernel NULL pointer dereference at           (null)                                    
Mar 15 17:58:04 mainhost kernel: [65866.977422] IP: [<ffffffff8100efbe>] 0xffffffff8100efbe                                                                  
Mar 15 17:58:04 mainhost kernel: [65866.977663] PGD 7387b7067 PUD 81b723067 PMD 0.                                                                           
Mar 15 17:58:04 mainhost kernel: [65866.977902] Oops: 0000 [#1] SMP.                                                                                         
Mar 15 17:58:04 mainhost kernel: [65866.978128] last sysfs file: /sys/devices/system/cpu/cpu3/topology/thread_siblings                                       
Mar 15 17:58:04 mainhost kernel: [65866.978572] CPU 1.                                                                                                       
Mar 15 17:58:04 mainhost kernel: [65866.978577] Modules linked in: nfs lockd nfs_acl auth_rpcgss sunrpc ebtable_nat ebtables coretemp bridge stp llc xt_state
Mar 15 17:58:04 mainhost kernel: [65866.979737].                                                                                                             
Mar 15 17:58:04 mainhost kernel: [65866.979959] Pid: 3369, comm: qemu-system-x86 Not tainted 2.6.37-gentoo-r2 #2 Intel S5000VSA/S5000VSA                     
Mar 15 17:58:04 mainhost kernel: [65866.980085] RIP: 0010:[<ffffffff8100efbe>]  [<ffffffff8100efbe>] 0xffffffff8100efbe                                      
Mar 15 17:58:04 mainhost kernel: [65866.980085] RSP: 0018:ffff880738767a48  EFLAGS: 00010246                                                                 
Mar 15 17:58:04 mainhost kernel: [65866.980085] RAX: 0000000000000000 RBX: fffffffffffff001 RCX: ffff88081cbeb948                                            
Mar 15 17:58:04 mainhost kernel: [65866.980085] RDX: 0000000000000022 RSI: fffffffffffff001 RDI: ffff88081cbeb000                                            
Mar 15 17:58:04 mainhost kernel: [65866.980085] RBP: 0000000000000001 R08: 00000000000fee01 R09: 0000000000000022                                            
Mar 15 17:58:04 mainhost kernel: [65866.980085] R10: 0000008000000000 R11: ffffea0000000000 R12: ffff880818d83490                                            
Mar 15 17:58:04 mainhost kernel: [65866.980085] R13: 00000000155e5000 R14: 0000000000000000 R15: 0000000000000100                                            
Mar 15 17:58:04 mainhost kernel: [65866.980085] FS:  00007f5f25e4e700(0000) GS:ffff88009f680000(0000) knlGS:fffff80001175000                                 
Mar 15 17:58:04 mainhost kernel: [65866.980085] CS:  0010 DS: 002b ES: 002b CR0: 000000008005003b                                                            
Mar 15 17:58:04 mainhost kernel: [65866.980085] CR2: 0000000000000000 CR3: 0000000806be9000 CR4: 00000000000426e0                                            
Mar 15 17:58:04 mainhost kernel: [65866.980085] DR0: 0000000000000045 DR1: 0000000000000000 DR2: 0000000000000000                                            
Mar 15 17:58:04 mainhost kernel: [65866.980085] DR3: 0000000000000005 DR6: 00000000ffff0ff0 DR7: 0000000000000400                                            
Mar 15 17:58:04 mainhost kernel: [65866.980085] Process qemu-system-x86 (pid: 3369, threadinfo ffff880738766000, task ffff8808203ac360)                      
Mar 15 17:58:04 mainhost kernel: [65866.980085] Stack:                                                                                                       
Mar 15 17:58:04 mainhost kernel: [65866.980085]  0000000000000000 ffff8806a30f3ff8 ffff880753980000 ffffffff8100f06f                                         
Mar 15 17:58:04 mainhost kernel: [65866.980085]  0000000000000ff8 ffff8807705d6b40 0000000000000ff8 ffffffff810123f0                                         
Mar 15 17:58:04 mainhost kernel: [65866.980085]  0000000000000000 0000000000000000 0000000000000000 0000000000000000                                         
Mar 15 17:58:04 mainhost kernel: [65866.980085] Call Trace:                                                                                                  
Mar 15 17:58:04 mainhost kernel: [65866.980085]  [<ffffffff8100f06f>] ? 0xffffffff8100f06f                                                                   
Mar 15 17:58:04 mainhost kernel: [65866.980085]  [<ffffffff810123f0>] ? 0xffffffff810123f0                                                                   
Mar 15 17:58:04 mainhost kernel: [65866.980085]  [<ffffffff8100f744>] ? 0xffffffff8100f744                                                                   
Mar 15 17:58:04 mainhost kernel: [65866.980085]  [<ffffffff8100ffaf>] ? 0xffffffff8100ffaf                                                                   
Mar 15 17:58:04 mainhost kernel: [65866.980085]  [<ffffffff810011f1>] ? 0xffffffff810011f1                                                                   
Mar 15 17:58:04 mainhost kernel: [65866.980085]  [<ffffffff810142fc>] ? 0xffffffff810142fc                                                                   
Mar 15 17:58:04 mainhost kernel: [65866.980085]  [<ffffffff8100834d>] ? 0xffffffff8100834d                                                                   
Mar 15 17:58:04 mainhost kernel: [65866.980085]  [<ffffffff81011af6>] ? 0xffffffff81011af6                                                                   
Mar 15 17:58:04 mainhost kernel: [65866.980085]  [<ffffffff8100c5a7>] ? 0xffffffff8100c5a7                                                                   
Mar 15 17:58:04 mainhost kernel: [65866.980085]  [<ffffffff81003a85>] ? 0xffffffff81003a85                                                                   
Mar 15 17:58:04 mainhost kernel: [65866.980085]  [<ffffffff810e19b0>] ? 0xffffffff810e19b0                                                                   
Mar 15 17:58:04 mainhost kernel: [65866.980085]  [<ffffffff81078cd8>] ? 0xffffffff81078cd8                                                                   
Mar 15 17:58:04 mainhost kernel: [65866.980085]  [<ffffffff810e1a39>] ? 0xffffffff810e1a39                                                                   
Mar 15 17:58:04 mainhost kernel: [65866.980085]  [<ffffffff810267fb>] ? 0xffffffff810267fb                                                                   
Mar 15 17:58:04 mainhost kernel: [65866.980085] Code: 8b 47 50 8d 50 01 85 c0 89 57 50 75 07 41 58 e9 32 ff ff ff 5f c3 55 89 d5 53 48 89 f3 48 83 ec 08 e8 d
Mar 15 17:58:04 mainhost kernel: [65866.980085] RIP  [<ffffffff8100efbe>] 0xffffffff8100efbe                                                                 
Mar 15 17:58:04 mainhost kernel: [65866.980085]  RSP <ffff880738767a48>                                                                                      
Mar 15 17:58:04 mainhost kernel: [65866.980085] CR2: 0000000000000000                                                                                        
Mar 15 17:58:04 mainhost kernel: [65866.990753] ---[ end trace d147f74976c2654d ]---

In what may be the reason? This is a bug or error settings?

Code: Select all

mainhost log # uname -a
Linux mainhost 2.6.37-gentoo-r2 #2 SMP Mon Mar 14 22:53:20 MSK 2011 x86_64 Intel(R) Xeon(R) CPU E5405 @ 2.00GHz GenuineIntel GNU/Linux

mainhost log # emerge qemu-kvm libvirt -pv
[ebuild   R   ] app-emulation/qemu-kvm-0.13.0-r2  USE="aio ncurses ssl -alsa -bluetooth -brltty -curl -esd -fdt -hardened -jpeg -png -pulseaudio -qemu-ifup -sasl -sdl -static -vde" QEMU_SOFTMMU_TARGETS="arm cris i386 m68k microblaze mips mips64 mips64el mipsel ppc ppc64 ppcemb sh4 sh4eb sparc sparc64 x86_64" QEMU_USER_TARGETS="alpha arm armeb cris i386 m68k microblaze mips mipsel ppc ppc64 ppc64abi32 sh4 sh4eb sparc sparc32plus sparc64 x86_64" 0 kB
[ebuild   R   ] app-emulation/libvirt-0.8.8-r1  USE="json libvirtd lvm network nfs nls qemu virt-network -avahi -caps -debug -iscsi -lxc -macvtap -numa -openvz -parted -pcap -phyp -policykit -python -sasl (-selinux) -udev -uml -virtualbox -xen" 0 kB                                                                 

mainhost log # ps ax|grep qemu
 2957 ?        Sl    12:28 /usr/bin/qemu-system-x86_64 --enable-kvm -S -M pc-0.12 -enable-kvm -m 512 -smp 1,sockets=1,cores=1,threads=1 -name dc1 -uuid f090bfc9-1cab-e4e9-51ea-80c9cc775bff -nodefconfig -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/dc1.monitor,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=localtime -boot order=c,menu=off -drive file=/dev/vm-storage/dc1,if=none,id=drive-ide0-0-0,format=raw -device ide-drive,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0 -drive if=none,media=cdrom,id=drive-ide0-1-0,readonly=on,format=raw -device ide-drive,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0 -netdev tap,fd=13,id=hostnet0 -device rtl8139,netdev=hostnet0,id=net0,mac=52:54:00:7e:a1:a7,bus=pci.0,addr=0x4 -usb -device usb-tablet,id=input0 -vnc 0.0.0.0:0,password -vga cirrus -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3
 2982 ?        Rl    10:34 /usr/bin/qemu-system-x86_64 --enable-kvm -S -M pc-0.12 -enable-kvm -m 1024 -smp 1,sockets=1,cores=1,threads=1 -name transarchive -uuid b96a3481-1ad6-9329-387e-a1504a17d0ee -nodefconfig -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/transarchive.monitor,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=localtime -boot order=c,menu=off -drive file=/dev/vm-storage/transarchive,if=none,id=drive-ide0-0-0,format=raw -device ide-drive,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0 -drive if=none,media=cdrom,id=drive-ide0-1-0,readonly=on,format=raw -device ide-drive,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0 -netdev tap,fd=13,id=hostnet0,vhost=on,vhostfd=17 -device virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:a9:f8:06,bus=pci.0,addr=0x3 -usb -device usb-tablet,id=input0 -vnc 0.0.0.0:3,password -vga std -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x4

(sorry for my bad english)

Post by Hu » Wed Mar 16, 2011 2:06 am

akam wrote:
Code: Select all
Mar 15 17:58:04 mainhost kernel: [65866.976982] BUG: unable to handle kernel NULL pointer dereference at           (null)
In what may be the reason? This is a bug or error settings?

This is a bug, as noted by the first line of output you pasted. No configuration error should ever result in a kernel NULL pointer dereference.

The call trace does not seem very useful. Can you rebuild the kernel with appropriate debugging information and retry? You might also be able to determine the addresses for the existing crash by cross-referencing them with the System.map.

qemu, kernel breaks

qemu, kernel breaks

Re: qemu, kernel breaks