this answers the whole question. Thanks a lot. closing
** Changed in: qemu
Status: New => Invalid
--
You received this bug notification because you are a member of qemu-
devel-ml, which is subscribed to QEMU.
https://bugs.launchpad.net/bugs/1860759
Title:
[REGRESSION] option `-snapshot` ignored with blockdev
Status in QEMU:
Invalid
Bug description:
After upgrade of qemu 3.1.0 → 4.2.0 I found that running with libvirt doesn't
honor `-snapshot` option anymore. I.e. disk images get modified.
Using `-hda` option honors `-snapshot`
So I made a test case without libvirt. Testcase using 4.2.0:
> qemu -hda tmp-16G.img -cdrom regular-rescue-latest-x86_64.iso -m 2G
This works fine and tmp-16G.img stays unmodified.
But:
> /usr/bin/qemu-system-x86_64 -name guest=test-linux,debug-threads=on -S
-machine pc-i440fx-3.1,accel=kvm,usb=off,vmport=off,dump-guest-core=off -cpu
Broadwell-noTSX,vme=on,ss=on,f16c=on,rdrand=on,hypervisor=on,arat=on,tsc-adjust=on,xsaveopt=on,pdpe1gb=on,abm=on
-m 2048 -overcommit mem-lock=off -smp 3,sockets=3,cores=1,threads=1 -uuid
d32a9191-f51d-4fae-a419-b73d85b49198 -no-user-config -nodefaults -rtc
base=utc,driftfix=slew -global kvm-pit.lost_tick_policy=delay -no-hpet
-no-shutdown -global PIIX4_PM.disable_s3=1 -global PIIX4_PM.disable_s4=1 -boot
strict=on -device ich9-usb-ehci1,id=usb,bus=pci.0,addr=0x5.0x7 -device
ich9-usb-uhci1,masterbus=usb.0,firstport=0,bus=pci.0,multifunction=on,addr=0x5
-device ich9-usb-uhci2,masterbus=usb.0,firstport=2,bus=pci.0,addr=0x5.0x1
-device ich9-usb-uhci3,masterbus=usb.0,firstport=4,bus=pci.0,addr=0x5.0x2
-blockdev
\{\"driver\":\"file\",\"filename\":\"/tmp/regular-rescue-latest-x86_64.iso\",\"node-name\":\"libvirt-2-storage\",\"auto-read-only\":true,\"discard\":\"unmap\"}
-blockdev
\{\"node-name\":\"libvirt-2-format\",\"read-only\":true,\"driver\":\"raw\",\"file\":\"libvirt-2-storage\"}
-device ide-cd,bus=ide.0,unit=0,drive=libvirt-2-format,id=ide0-0-0,bootindex=1
-blockdev
\{\"driver\":\"file\",\"filename\":\"/tmp/tmp-2G.img\",\"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.0,addr=0x7,drive=libvirt-1-format,id=virtio-disk0
-netdev user,id=hostnet0 -device
e1000,netdev=hostnet0,id=net0,mac=52:54:00:ab:d8:29,bus=pci.0,addr=0x3 -chardev
pty,id=charserial0 -device isa-serial,chardev=charserial0,id=serial0 -device
qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vram64_size_mb=0,vgamem_mb=16,max_outputs=1,bus=pci.0,addr=0x2
-device intel-hda,id=sound0,bus=pci.0,addr=0x4 -device
hda-duplex,id=sound0-codec0,bus=sound0.0,cad=0 -device
virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x6 -snapshot -sandbox
on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny -msg
timestamp=on
This modifies tmp-16G.img.
To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1860759/+subscriptions
