Re: [Qemu-devel] E5-2620v2 - emulation stop error

[Andrey Korolyov]

On Thu, Mar 26, 2015 at 5:47 AM, Bandan Das <address@hidden> wrote:
> Hi Andrey,
>
> Andrey Korolyov <address@hidden> writes:
>
>> On Mon, Mar 16, 2015 at 10:17 PM, Andrey Korolyov <address@hidden> wrote:
>>> For now, it looks like bug have a mixed Murphy-Heisenberg nature, as
>>> it appearance is very rare (compared to the number of actual launches)
>>> and most probably bounded to the physical characteristics of my
>>> production nodes. As soon as I reach any reproducible path for a
>>> regular workstation environment, I`ll let everyone know. Also I am
>>> starting to think that issue can belong to the particular motherboard
>>> firmware revision, despite fact that the CPU microcode is the same
>>> everywhere.
>
> I will take the risk and say this - "could it be a processor bug ?" :)
>
>>
>> Hello everyone, I`ve managed to reproduce this issue
>> *deterministically* with latest seabios with smp fix and 3.18.3. The
>> error occuring just *once* per vm until hypervisor reboots, at least
>> in my setup, this is definitely crazy...
>>
>> - launch two VMs (Centos 7 in my case),
>> - wait a little while they are booting,
>> - attach serial console (I am using virsh list for this exact purpose),
>> - issue acpi reboot or reset, does not matter,
>> - VM always hangs at boot, most times with sgabios initialization
>> string printed out [1], but sometimes it hangs a bit later [2],
>> - no matter how many times I try to relaunch the QEMU afterwards, the
>> issue does not appear on VM which experienced problem once;
>> - trace and sample args can be seen in [3] and [4] respectively.
>
> My system is a Dell R720 dual socket which has 2620v2s. I tried your
> setup but couldn't reproduce (my qemu cmdline isn't exactly the same
> as yours), although, if you could simplify your command line a bit,
> I can try again.
>
> Bandan
>
>> 1)
>> Google, Inc.
>> Serial Graphics Adapter 06/11/14
>> SGABIOS $Id: sgabios.S 8 2010-04-22 00:03:40Z nlaredo $
>> (address@hidden) Wed Jun 11 05:57:34 UTC 2014
>> Term: 211x62
>> 4 0
>>
>> 2)
>> Google, Inc.
>> Serial Graphics Adapter 06/11/14
>> SGABIOS $Id: sgabios.S 8 2010-04-22 00:03:40Z nlaredo $
>> (address@hidden) Wed Jun 11 05:57:34 UTC 2014
>> Term: 211x62
>> 4 0
>> [...empty screen...]
>> SeaBIOS (version 1.8.1-20150325_230423-testnode)
>> Machine UUID 3c78721f-7317-4f85-bcbe-f5ad46d293a1
>>
>>
>> iPXE (http://ipxe.org) 00:02.0 C100 PCI2.10 PnP PMM+3FF95BA0+3FEF5BA0 C10
>>
>> 3)
>>
>> KVM internal error. Suberror: 2
>> extra data[0]: 800000ef
>> extra data[1]: 80000b0d
>> EAX=00000000 EBX=00000000 ECX=00000000 EDX=00000000
>> ESI=00000000 EDI=00000000 EBP=00000000 ESP=00006d2c
>> EIP=0000d331 EFL=00010202 [-------] CPL=0 II=0 A20=1 SMM=0 HLT=0
>> ES =0000 00000000 0000ffff 00009300
>> CS =f000 000f0000 0000ffff 00009b00
>> SS =0000 00000000 0000ffff 00009300
>> DS =0000 00000000 0000ffff 00009300
>> FS =0000 00000000 0000ffff 00009300
>> GS =0000 00000000 0000ffff 00009300
>> LDT=0000 00000000 0000ffff 00008200
>> TR =0000 00000000 0000ffff 00008b00
>> GDT=     000f6cb0 00000037
>> IDT=     00000000 000003ff
>> CR0=00000010 CR2=00000000 CR3=00000000 CR4=00000000
>> DR0=0000000000000000 DR1=0000000000000000 DR2=0000000000000000
>> DR3=0000000000000000
>> DR6=00000000ffff0ff0 DR7=0000000000000400
>> EFER=0000000000000000
>> Code=66 c3 cd 02 cb cd 10 cb cd 13 cb cd 15 cb cd 16 cb cd 18 cb <cd>
>> 19 cb cd 1c cb cd 4a cb fa fc 66 ba 47 d3 0f 00 e9 ad fe f3 90 f0 0f
>> ba 2d d4 fe fb 3f
>>
>> 4)
>> /usr/bin/qemu-system-x86_64 -name centos71 -S -machine
>> pc-i440fx-2.1,accel=kvm,usb=off -cpu SandyBridge,+kvm_pv_eoi -bios
>> /usr/share/seabios/bios.bin -m 1024 -realtime mlock=off -smp
>> 12,sockets=1,cores=12,threads=12 -uuid
>> 3c78721f-7317-4f85-bcbe-f5ad46d293a1 -nographic -no-user-config
>> -nodefaults -device sga -chardev
>> socket,id=charmonitor,path=/var/lib/libvirt/qemu/centos71.monitor,server,nowait
>> -mon chardev=charmonitor,id=monitor,mode=control -rtc
>> base=utc,driftfix=slew -global kvm-pit.lost_tick_policy=discard
>> -no-hpet -no-shutdown -global PIIX4_PM.disable_s3=1 -global
>> PIIX4_PM.disable_s4=1 -boot strict=on -device
>> nec-usb-xhci,id=usb,bus=pci.0,addr=0x3 -device
>> virtio-serial-pci,id=virtio-serial0,bus=pci.0,addr=0x4 -drive
>> file=rbd:dev-rack2/centos7-1.raw:id=qemukvm:key=XXXXXXXXXXXXXXXXXXXXXXXXXX:auth_supported=cephx\;none:mon_host=10.6.0.1\:6789\;10.6.0.3\:6789\;10.6.0.4\:6789,if=none,id=drive-virtio-disk0,format=raw,cache=writeback,aio=native
>> -device 
>> virtio-blk-pci,scsi=off,bus=pci.0,addr=0x5,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1
>> -chardev pty,id=charserial0 -device
>> isa-serial,chardev=charserial0,id=serial0 -chardev
>> socket,id=charchannel0,path=/var/lib/libvirt/qemu/centos71.sock,server,nowait
>> -device 
>> virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=org.qemu.guest_agent.1
>> -msg timestamp=on

Hehe, 2.2 works just perfectly but 2.1 isn`t. I`ll bisect the issue in
a next couple of days and post the right commit (but as can remember
none of commits b/w 2.1 and 2.2 can fix simular issue by a purpose).
I`ve attached a reference xml to simplify playing with libvirt if
anyone willing to do so.

centos71.xml
Description: Text Data