RE: External snapshots and using qemu without libvirt
Thanks for your suggestion. I had gotten the command line from the libvirt log
file, but I ran the ps fax check as a comparison. There was no meaningful
difference between what was in the log file and on the command line.
So I looked at other options and tried a bunch of -display options. Many of
them don't work with the version of qemu that comes installed on RHEL 8, qemu
gtk, etc. didn't work.
I am able to get a spice server up and connect to it. But the spice-screen
remains black. If I kill the qemu process it disconnects, so it's definitely
the correct spice server. ANyone see that issue before? (If I put on "-vnc
:0" the vnc client will tell me "client has not initialized the display (yet)")
Jim
-Original Message-
From: Qemu-discuss On Behalf
Of Simon Becherer
Sent: Monday, September 13, 2021 8:20 AM
To: qemu-discuss@nongnu.org
Subject: Re: External snapshots and using qemu without libvirt
Am 13.09.21 um 16:34 schrieb Leek, Jim:
> I'm still messing about with qemu snapshots. I have internal snapshots
> working OK. But I read this in the RHEL documentation: "Important: Red Hat
> recommends the use of external snapshots." Then on a later page I found this:
> "However, external snapshots are currently not fully implemented on Red Hat
> Enterprise Linux 7, and are not available when using virt-manager."Ha!
>
> Maybe external snapshots will work if I run qemu without libvirt? But
> I'm having trouble getting that to work as well. I found this page
> and followed the instructions:
> https://developers.redhat.com/blog/2020/03/06/configure-and-run-a-qemu
> -based-vm-outside-of-libvirt (although he talks about
> qemu-system-x86_64 and I'm using qemu-kvm, but I hope that doesn't
> make any difference.)
>
> But I can't get it to work. I've tried a number of modifications, and the
> command line below launches the VM, but I can't access it. No screen pops
> up, and I can't get there via ssh. If I take off the last lines about the
> display it will say I can use VNC ::1:5900, but when I connect there it with
> a VNC client it just says "guest has not initialized display yet."
>
> Anybody have any ideas on any of this?
> Thanks
>
> Here's the command line I've tried. The removing the last 2 arguments does
> change the display behavior, but not to any particular benefit:
> #! /bin/sh
> export LC_ALL=C
> export PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin
> export HOME=/var/lib/libvirt/qemu/domain-6-centos8_3
> export
> XDG_DATA_HOME=/var/lib/libvirt/qemu/domain-6-centos8_3/.local/share
> export XDG_CACHE_HOME=/var/lib/libvirt/qemu/domain-6-centos8_3/.cache
> export
> XDG_CONFIG_HOME=/var/lib/libvirt/qemu/domain-6-centos8_3/.config
> export QEMU_AUDIO_DRV=spice
> /usr/libexec/qemu-kvm \
> -name guest=centos8_3,debug-threads=on \ -S \ -enable-fips \ -machine
> pc-q35-rhel8.2.0,accel=kvm,usb=off,vmport=off,dump-guest-core=off \
> -cpu
> Skylake-Server-IBRS,ss=on,vmx=on,pdcm=on,hypervisor=on,tsc-adjust=on,c
> lflushopt=on,umip=on,pku=on,md-clear=on,stibp=on,arch-capabilities=on,
> ssbd=on,xsaves=on,ibpb=on,ibrs=on,amd-stibp=on,amd-ssbd=on,skip-l1dfl-
> vmentry=on,pschange-mc-no=on \ -m 24000 \ -overcommit mem-lock=off \
> -smp 2,sockets=2,cores=1,threads=1 \ -uuid
> 8dd20f24-3e31-464c-956e-67d3d9f2a83c \ -no-user-config \ -rtc
> base=utc,driftfix=slew \ -global kvm-pit.lost_tick_policy=delay \
> -no-hpet \ -no-shutdown \ -global ICH9-LPC.disable_s3=1 \ -global
> ICH9-LPC.disable_s4=1 \ -boot strict=on \ -device
> pcie-root-port,port=0x10,chassis=1,id=pci.1,bus=pcie.0,multifunction=o
> n,addr=0x2 \ -device
> pcie-root-port,port=0x11,chassis=2,id=pci.2,bus=pcie.0,addr=0x2.0x1 \
> -device
> pcie-root-port,port=0x12,chassis=3,id=pci.3,bus=pcie.0,addr=0x2.0x2 \
> -device
> pcie-root-port,port=0x13,chassis=4,id=pci.4,bus=pcie.0,addr=0x2.0x3 \
> -device
> pcie-root-port,port=0x14,chassis=5,id=pci.5,bus=pcie.0,addr=0x2.0x4 \
> -device
> pcie-root-port,port=0x15,chassis=6,id=pci.6,bus=pcie.0,addr=0x2.0x5 \
> -device
> pcie-root-port,port=0x16,chassis=7,id=pci.7,bus=pcie.0,addr=0x2.0x6 \
> -device
> pcie-root-port,port=0x17,chassis=8,id=pci.8,bus=pcie.0,addr=0x2.0x7 \
> -device pcie-pci-bridge,id=pci.9,bus=pci.1,addr=0x0 \ -device
> qemu-xhci,p2=15,p3=15,id=usb,bus=pci.2,addr=0x0 \ -device
> virtio-serial-pci,id=virtio-serial0,bus=pci.3,addr=0x0 \ -blockdev
> '{"driver":"file","filename":"/home/leek2/qemu/rhel8_1-clone-1.qcow2",
> "node-name":"libvirt-1-storage","auto-read-only":true,"discard":"unmap
> "}' \ -blockdev
> '{"node-name":"libvirt-1-format","read-only":false,"driver":"qcow2","f
> ile":"libvirt-1-storage","backing":null}' \ -device
> virtio-blk-pci,scsi=off,bus=pci.4,addr=0x0,drive=libvirt-1-format,id=v
> irtio-disk0,bootindex=1 \ -device
> virtio-net-pci,netdev=hostnet0,id=net0,mac=6c:2b:59:e9:44:49,bus=pci.7
> ,addr=0x0 \ -netdev bridge,id=hostnet0,br=virbr0 \ -chardev
> spicevmc,id=charchannel0,name=vdagent \
Re: External snapshots and using qemu without libvirt
Am 13.09.21 um 16:34 schrieb Leek, Jim:
> I'm still messing about with qemu snapshots. I have internal snapshots
> working OK. But I read this in the RHEL documentation: "Important: Red Hat
> recommends the use of external snapshots." Then on a later page I found this:
> "However, external snapshots are currently not fully implemented on Red Hat
> Enterprise Linux 7, and are not available when using virt-manager."Ha!
>
> Maybe external snapshots will work if I run qemu without libvirt? But I'm
> having trouble getting that to work as well. I found this page and followed
> the instructions:
> https://developers.redhat.com/blog/2020/03/06/configure-and-run-a-qemu-based-vm-outside-of-libvirt
> (although he talks about qemu-system-x86_64 and I'm using qemu-kvm, but I
> hope that doesn't make any difference.)
>
> But I can't get it to work. I've tried a number of modifications, and the
> command line below launches the VM, but I can't access it. No screen pops
> up, and I can't get there via ssh. If I take off the last lines about the
> display it will say I can use VNC ::1:5900, but when I connect there it with
> a VNC client it just says "guest has not initialized display yet."
>
> Anybody have any ideas on any of this?
> Thanks
>
> Here's the command line I've tried. The removing the last 2 arguments does
> change the display behavior, but not to any particular benefit:
> #! /bin/sh
> export LC_ALL=C
> export PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin
> export HOME=/var/lib/libvirt/qemu/domain-6-centos8_3
> export XDG_DATA_HOME=/var/lib/libvirt/qemu/domain-6-centos8_3/.local/share
> export XDG_CACHE_HOME=/var/lib/libvirt/qemu/domain-6-centos8_3/.cache
> export XDG_CONFIG_HOME=/var/lib/libvirt/qemu/domain-6-centos8_3/.config
> export QEMU_AUDIO_DRV=spice
> /usr/libexec/qemu-kvm \
> -name guest=centos8_3,debug-threads=on \
> -S \
> -enable-fips \
> -machine pc-q35-rhel8.2.0,accel=kvm,usb=off,vmport=off,dump-guest-core=off \
> -cpu
> Skylake-Server-IBRS,ss=on,vmx=on,pdcm=on,hypervisor=on,tsc-adjust=on,clflushopt=on,umip=on,pku=on,md-clear=on,stibp=on,arch-capabilities=on,ssbd=on,xsaves=on,ibpb=on,ibrs=on,amd-stibp=on,amd-ssbd=on,skip-l1dfl-vmentry=on,pschange-mc-no=on
> \
> -m 24000 \
> -overcommit mem-lock=off \
> -smp 2,sockets=2,cores=1,threads=1 \
> -uuid 8dd20f24-3e31-464c-956e-67d3d9f2a83c \
> -no-user-config \
> -rtc base=utc,driftfix=slew \
> -global kvm-pit.lost_tick_policy=delay \
> -no-hpet \
> -no-shutdown \
> -global ICH9-LPC.disable_s3=1 \
> -global ICH9-LPC.disable_s4=1 \
> -boot strict=on \
> -device
> pcie-root-port,port=0x10,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x2
> \
> -device pcie-root-port,port=0x11,chassis=2,id=pci.2,bus=pcie.0,addr=0x2.0x1 \
> -device pcie-root-port,port=0x12,chassis=3,id=pci.3,bus=pcie.0,addr=0x2.0x2 \
> -device pcie-root-port,port=0x13,chassis=4,id=pci.4,bus=pcie.0,addr=0x2.0x3 \
> -device pcie-root-port,port=0x14,chassis=5,id=pci.5,bus=pcie.0,addr=0x2.0x4 \
> -device pcie-root-port,port=0x15,chassis=6,id=pci.6,bus=pcie.0,addr=0x2.0x5 \
> -device pcie-root-port,port=0x16,chassis=7,id=pci.7,bus=pcie.0,addr=0x2.0x6 \
> -device pcie-root-port,port=0x17,chassis=8,id=pci.8,bus=pcie.0,addr=0x2.0x7 \
> -device pcie-pci-bridge,id=pci.9,bus=pci.1,addr=0x0 \
> -device qemu-xhci,p2=15,p3=15,id=usb,bus=pci.2,addr=0x0 \
> -device virtio-serial-pci,id=virtio-serial0,bus=pci.3,addr=0x0 \
> -blockdev
> '{"driver":"file","filename":"/home/leek2/qemu/rhel8_1-clone-1.qcow2","node-name":"libvirt-1-storage","auto-read-only":true,"discard":"unmap"}'
> \
> -blockdev
> '{"node-name":"libvirt-1-format","read-only":false,"driver":"qcow2","file":"libvirt-1-storage","backing":null}'
> \
> -device
> virtio-blk-pci,scsi=off,bus=pci.4,addr=0x0,drive=libvirt-1-format,id=virtio-disk0,bootindex=1
> \
> -device
> virtio-net-pci,netdev=hostnet0,id=net0,mac=6c:2b:59:e9:44:49,bus=pci.7,addr=0x0
> \
> -netdev bridge,id=hostnet0,br=virbr0 \
> -chardev spicevmc,id=charchannel0,name=vdagent \
> -device
> virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel0,id=channel0,name=com.redhat.spice.0
> \
> -device virtio-balloon-pci,id=balloon0,bus=pci.5,addr=0x0 \
> -object rng-random,id=objrng0,filename=/dev/urandom \
> -device virtio-rng-pci,rng=objrng0,id=rng0,bus=pci.6,addr=0x0 \
> -msg timestamp=on \
> -device
> qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vram64_size_mb=0,vgamem_mb=16,max_outputs=1,bus=pcie.0,addr=0x1
> \
> -spice
> port=5900,addr=127.0.0.1,disable-ticketing,image-compression=off,seamless-migration=on
>
Without checking all of your config:
> -spice
> port=5900,addr=127.0.0.1,disable-ticketing,image-compression=off,seamless-migration=on
should be: disable-ticketing=on
i would suggest you fire up your quemu with libvirt and then check the
generated startline
with
ps fax |grep qemu
regards,
simoN
--
www.becherer.de
signature.asc
Description: OpenPGP digital signature
External snapshots and using qemu without libvirt
I'm still messing about with qemu snapshots. I have internal snapshots working
OK. But I read this in the RHEL documentation: "Important: Red Hat recommends
the use of external snapshots." Then on a later page I found this: "However,
external snapshots are currently not fully implemented on Red Hat Enterprise
Linux 7, and are not available when using virt-manager."Ha!
Maybe external snapshots will work if I run qemu without libvirt? But I'm
having trouble getting that to work as well. I found this page and followed
the instructions:
https://developers.redhat.com/blog/2020/03/06/configure-and-run-a-qemu-based-vm-outside-of-libvirt
(although he talks about qemu-system-x86_64 and I'm using qemu-kvm, but I hope
that doesn't make any difference.)
But I can't get it to work. I've tried a number of modifications, and the
command line below launches the VM, but I can't access it. No screen pops up,
and I can't get there via ssh. If I take off the last lines about the display
it will say I can use VNC ::1:5900, but when I connect there it with a VNC
client it just says "guest has not initialized display yet."
Anybody have any ideas on any of this?
Thanks
Here's the command line I've tried. The removing the last 2 arguments does
change the display behavior, but not to any particular benefit:
#! /bin/sh
export LC_ALL=C
export PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin
export HOME=/var/lib/libvirt/qemu/domain-6-centos8_3
export XDG_DATA_HOME=/var/lib/libvirt/qemu/domain-6-centos8_3/.local/share
export XDG_CACHE_HOME=/var/lib/libvirt/qemu/domain-6-centos8_3/.cache
export XDG_CONFIG_HOME=/var/lib/libvirt/qemu/domain-6-centos8_3/.config
export QEMU_AUDIO_DRV=spice
/usr/libexec/qemu-kvm \
-name guest=centos8_3,debug-threads=on \
-S \
-enable-fips \
-machine pc-q35-rhel8.2.0,accel=kvm,usb=off,vmport=off,dump-guest-core=off \
-cpu
Skylake-Server-IBRS,ss=on,vmx=on,pdcm=on,hypervisor=on,tsc-adjust=on,clflushopt=on,umip=on,pku=on,md-clear=on,stibp=on,arch-capabilities=on,ssbd=on,xsaves=on,ibpb=on,ibrs=on,amd-stibp=on,amd-ssbd=on,skip-l1dfl-vmentry=on,pschange-mc-no=on
\
-m 24000 \
-overcommit mem-lock=off \
-smp 2,sockets=2,cores=1,threads=1 \
-uuid 8dd20f24-3e31-464c-956e-67d3d9f2a83c \
-no-user-config \
-rtc base=utc,driftfix=slew \
-global kvm-pit.lost_tick_policy=delay \
-no-hpet \
-no-shutdown \
-global ICH9-LPC.disable_s3=1 \
-global ICH9-LPC.disable_s4=1 \
-boot strict=on \
-device
pcie-root-port,port=0x10,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x2
\
-device pcie-root-port,port=0x11,chassis=2,id=pci.2,bus=pcie.0,addr=0x2.0x1 \
-device pcie-root-port,port=0x12,chassis=3,id=pci.3,bus=pcie.0,addr=0x2.0x2 \
-device pcie-root-port,port=0x13,chassis=4,id=pci.4,bus=pcie.0,addr=0x2.0x3 \
-device pcie-root-port,port=0x14,chassis=5,id=pci.5,bus=pcie.0,addr=0x2.0x4 \
-device pcie-root-port,port=0x15,chassis=6,id=pci.6,bus=pcie.0,addr=0x2.0x5 \
-device pcie-root-port,port=0x16,chassis=7,id=pci.7,bus=pcie.0,addr=0x2.0x6 \
-device pcie-root-port,port=0x17,chassis=8,id=pci.8,bus=pcie.0,addr=0x2.0x7 \
-device pcie-pci-bridge,id=pci.9,bus=pci.1,addr=0x0 \
-device qemu-xhci,p2=15,p3=15,id=usb,bus=pci.2,addr=0x0 \
-device virtio-serial-pci,id=virtio-serial0,bus=pci.3,addr=0x0 \
-blockdev
'{"driver":"file","filename":"/home/leek2/qemu/rhel8_1-clone-1.qcow2","node-name":"libvirt-1-storage","auto-read-only":true,"discard":"unmap"}'
\
-blockdev
'{"node-name":"libvirt-1-format","read-only":false,"driver":"qcow2","file":"libvirt-1-storage","backing":null}'
\
-device
virtio-blk-pci,scsi=off,bus=pci.4,addr=0x0,drive=libvirt-1-format,id=virtio-disk0,bootindex=1
\
-device
virtio-net-pci,netdev=hostnet0,id=net0,mac=6c:2b:59:e9:44:49,bus=pci.7,addr=0x0
\
-netdev bridge,id=hostnet0,br=virbr0 \
-chardev spicevmc,id=charchannel0,name=vdagent \
-device
virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel0,id=channel0,name=com.redhat.spice.0
\
-device virtio-balloon-pci,id=balloon0,bus=pci.5,addr=0x0 \
-object rng-random,id=objrng0,filename=/dev/urandom \
-device virtio-rng-pci,rng=objrng0,id=rng0,bus=pci.6,addr=0x0 \
-msg timestamp=on \
-device
qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vram64_size_mb=0,vgamem_mb=16,max_outputs=1,bus=pcie.0,addr=0x1
\
-spice
port=5900,addr=127.0.0.1,disable-ticketing,image-compression=off,seamless-migration=on
Problem with init debugging under QEMU ARM
Dear QEMU community, I'm now trying to fix bug in glibc which became apparent on qemu 6.0.0. The error is caused by glibc commit: bca0f5cbc9257c13322b99e55235c4f21ba0bd82 https://sourceware.org/git/?p=glibc.git;a=blobdiff;f=sysdeps/arm/dl-machine.h;h=eb13cb8b57496a0ec175c54a495f7e78db978fb7;hp=ff5e09e207f7986b1506b8895ae6c2aff032a380;hb=bca0f5cbc9257c13322b99e55235c4f21ba0bd82;hpb=34b4624b04fc8f038b2c329ca7560197320615b4 (reverting it causes the board to boot again) Other components: binutils_2.37 gcc_11.2 Yocto poky: SHA1: 1e2e9a84d6dd81d7f6dd69c0d119d0149d10ade1 Qemu start line (the problem is visible on 5.2.0 and 6.0.0): qemu-system-arm -device virtio-net-device,netdev=net0,mac=52:54:00:12:34:02 -netdev tap,id=net0,ifnam e=tap0,script=no,downscript=no -object rng-random,filename=/dev/urandom,id=rng0 -device virtio-rng-pci,rng=rng0 -drive id=disk0,file=y2038-image-devel-qemuarm.ext4,if=none,format =raw -device virtio-blk-device,drive=disk0 -device qemu-xhci -device usb-tablet -device usb-kbd -machine virt,highmem=off -cpu cortex-a15 -smp 4 -m 256 -serial mon:stdio -serial null -nographic -device VGA,edid=on -kernel zImage--5.10.62+git0+bce2813b16_machine-r0-qemuarm-20210910095636.bin -append 'root=/dev/vda rw mem=256M ip=192.168.7.2::192.168.7.1:255.255.255.0 console=ttyAMA0 console=hvc0 vmalloc=256 It has been tested with Cortex-A9 (Vexpress A9 2 core board) and Cortex-A15. I've also tested the v5.1, v5.10 and v5.14 kernels. The error is persistent. I do add -s and -S when starting qemu-system-arm. I can use gdb to debug the kernel without issues. Unfortunately, I'm not able to debug /sbin/init after switching contex to user space. Moreover, gdbserver cannot be used as the error (and kernel OOPs) is caused when early code from ld-linux.so.3 (the _dl_start function) is executed. Any hints on how to debug it? Inspecting assembler is one (awkward) option (some results presented below). I can also inspect the VMA of the code just before starting the /sbin/init process. Unfortunately, when I try to break on user space code it is not very helpful (as -S -s are supposed to be used with kernel). Some info with the eligible code (_dl_start function): -- I think that the problem may be with having the negative value calculated. The relevant snipet: 116c: bf00nop 116e: bf00nop 1170: bf00nop 1172: f8df 3508 ldr.w r3, [pc, #1288] ; 167c <_dl_start+0x520> 1176: f8df 1508 ldr.w r1, [pc, #1288] ; 1680 <_dl_start+0x524> 117a: 447badd r3, pc 117c: 4479add r1, pc 117e: f8c3 1598 str.w r1, [r3, #1432] ; 0x598 1182: bf00nop 1184: bf00nop 1186: bf00nop 1188: bf00nop 118a: bf00nop 118c: bf00nop 118e: f8df 24f4 ldr.w r2, [pc, #1268] ; 1684 <_dl_start+0x528> 1192: f8d3 5598 ldr.w r5, [r3, #1432] ; 0x598 1196: 447aadd r2, pc 1198: 442aadd r2, r5 119a: 1a52subsr2, r2, r1 119c: f8c3 25a0 str.w r2, [r3, #1440] ; 0x5a0 11a0: 6813ldr r3, [r2, #0] 167c: 0002be92.word 0x0002be92 1680: ee80.word 0xee80 The r1 gets the 0xee80 (negative offset) value. It is then added to pc and used to calculate r2. For working code (aforementioned patch reverted) - there are NO such large values (like aforementioned 0xee80). The arithmetic is done on 1690: 0020.word 0x0020 1694: 0002be7e.word 0x0002be7e which seems to work. Maybe I'm missing some flag when I do start qemu-system-arm? Thanks in advance for help and hints. -- Best regards, Łukasz Majewski pgpvwrDDsaHaf.pgp Description: OpenPGP digital signature
Re: TPM Module
On 9/13/21 4:25 AM, ToddAndMargo wrote: Hi All, Fedora 34 qemu-kvm-5.2.0-8.fc34.x86_64 I need a TPM module for Windows 11 Many thanks, -T Found it in the virtual machine manager. It was right under my nose!
Re: qemu-qvm: need an 8th gen CPU
On 9/13/21 2:53 AM, ToddAndMargo wrote: Hi All, I need an 8th gen CPU to get Windows 11 to upgrade properly. Which one of qemu-kvm's cpu's is 8th gen? Many thanks, -T Ooops, forgot Fedora 34 qemu-kvm-5.2.0-8.fc34.x86_64
TPM Module
Hi All, Fedora 34 qemu-kvm-5.2.0-8.fc34.x86_64 I need a TPM module for Windows 11 Many thanks, -T
qemu-qvm: need an 8th gen CPU
Hi All, I need an 8th gen CPU to get Windows 11 to upgrade properly. Which one of qemu-kvm's cpu's is 8th gen? Many thanks, -T -- A computer without Microsoft is like a chocolate cake without the mustard
