Use the right cow image and apply the second layer to provide read-write
access. The correct setup is:
- base image + base cow -> read-only snapshot (base changes "cached"
until committed)
- read-only snapshot + VM cow -> read-write snapshot (changes discarded
after VM shutdown)
This way, even VM without Qubes-specific startup scripts will can
benefit from Template VMs, while VMs with Qubes-specific startup scripts
may still see original root.img content (for possible signature
verification, when storage domain got implemented).
QubesOS/qubes-issues#2256
tar can't write archive with _contents_ of block device. We need this to
backup LVM-based disk images. To avoid dumping image to a file first,
create a simple tar archiver just for this purpose.
Python is not the fastest possible technology, it's 3 times slower than
equivalent written in C. But it's much easier to read, much less
error-prone, and still process 1GB image under 1s (CPU time, leaving
along actual disk reads). So, it's acceptable.
To ease all this, rework restore workflow: first create QubesVM objects,
and all their files (as for fresh VM), then override them with data
from backup - possibly redirecting some files to new location. This
allows generic code to create LVM volumes and then only restore its
content.
First part - handling firewall.xml and rules formatting.
Specification on https://qubes-os.org/doc/vm-interface/
TODO (for dom0):
- plug into QubesVM object
- expose rules in QubesDB (including reloading)
- drop old functions (vm.get_firewall_conf etc)
QubesOS/qubes-issues#1815
* core3-devices:
Fix core2migration and tests for new devices API
tests: more qubes.devices tests
qubes/ext/pci: implement pci-no-strict-reset/BDF feature
qubes/tools: allow calling qvm-device as qvm-devclass (like qvm-pci)
qubes: make pylint happy
qubes/tools: add qvm-device tool (and tests)
tests: load qubes.tests.tools.qvm_ls
tests: PCI devices tests
tests: add context manager to catch stdout
qubes/ext/pci: move PCI devices handling to an extension
qubes/devices: use more detailed exceptions than just KeyError
qubes/devices: allow non-persistent attach
qubes/storage: misc fixes for VM-exposed block devices handling
qubes: new devices API
FixesQubesOS/qubes-issues#2257
Instead of old per-VM flag 'pci_strictreset', now implement this as
per-device flag using features. To not fail on particular device
assignment set 'pci-no-strict-reset/DEVICE-BDF' to True. For
example 'pci-no-strict-reset/00:1b.0'.
QubesOS/qubes-issues#2257