Only first 4 disks can be emulated as IDE disks by QEMU. Specifically,
CDROM must be one of those first 4 disks, otherwise it will be
ignored. This is especially important if one wants to boot the VM from
that CDROM.
Since xvdd normally is a kernel-related volume (boot image, modules) it
makes perfect sense to re-use it for CDROM. It is either set for kernel
volume (in which case, VM should boot from it and not the CDROM), or
(possibly bootable) CDROM.
This needs to be done in two places:
- BlockExtension for dynamic attach
- libvirt xen.xml - for before-boot attach
In theory the latter would be enough, but it would be quite confusing
that device will get different options depending on when it's attached
(in addition to whether the kernel is set - introduced here).
This all also means, xvdd not always is a "system disk". Adjust listing
connected disks accordingly.
Libvirt XML syntax require lowercase utc as 'basis' attribute.
This option is used only if 'timezone' property is set. And apparently
libvirt prior to 4.1.0 didn't support it for Xen at all. Which means the
setting is ignore prior to Qubes R4.1.
If kernel package ships default-kernelopts-common.txt file, use that
instead of hardcoded Linux-specific options.
For Linux kernel it may include xen_scrub_pages=0 option, but only if
initrd shipped with this kernel re-enable this option later.
QubesOS/qubes-issues#4839QubesOS/qubes-issues#4736
Use maxmem=0 for disabling dynamic memory balance, instead of cryptic
service.meminfo-writer feature. Under the hood, meminfo-writer service
is also set based on maxmem property (directly in qubesdb, not
vm.features dict).
Having this as a property (not "feature"), allow to have sensible
handling of default value. Specifically, disable it automatically if
otherwise it would crash a VM. This is the case for:
- domain with PCI devices (PoD is not supported by Xen then)
- domain without balloon driver and/or meminfo-writer service
The check for the latter is heuristic (assume presence of 'qrexec' also
can indicate balloon driver support), but it is true for currently
supported systems.
This also allows more reliable control of libvirt config: do not set
memory != maxmem, unless qmemman is enabled.
memory != maxmem only makes sense if qmemman for given domain is
enabled. Besides wasting some domain resources for extra page tables
etc, for HVM domains this is harmful, because maxmem-memory difference
is made of Popupate-on-Demand pool, which - when depleted - will kill
the domain. This means domain without balloon driver will die as soon
as will try to use more than initial memory - but without balloon driver
it sees maxmem memory and doesn't know about the lower limit.
FixesQubesOS/qubes-issues#4135
Add 'no-default-kernelopts' feature to skip default hardcoded
Linux-specific kernelopts.
This is especially useful for non-Linux VMs (including Mirage OS).
FixesQubesOS/qubes-issues#4468
When dom0 do not provide the kernel, it should also not set kernel
command line in libvirt config. Otherwise qemu in stubdom fails to start
because it get -append option without -kernel, which is illegal
configuration.
FixesQubesOS/qubes-issues#3339
Add property for IPv6 address ('ip6'). Build default value similarly to
IPv4 - common prefix + QID or Disp ID (for DispVMs).
This all is disabled unless 'ipv6' feature is enabled. It is inherited
from netvm (not template).
Even when enabled, VM may decide to not use it - or simply not support
it.
QubesOS/qubes-issues#718
In contrast to the cirrus card emulation the vga card supports more
video modes. Since the qemu gui-agent bug [1] is now fixed we can switch
back to use it.
[1]: QubesOS/qubes-linux-utils@f14637a615
Linux kernel bug cause hypercall fails from HVM userspace (see
referenced issue). As a simple workaround, do not advertise SMAP to VMs
- but still use it as hypervisor level.
FixesQubesOS/qubes-issues#2881
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
Implement required event handlers according to documentation in
qubes.devices.
A modification of qubes.devices.DeviceInfo is needed to allow dynamic,
read-only properties.
QubesOS/qubes-issues#2257
Add 'backenddomain' element when source (not target) domain is not dom0.
Fix XML elemenet name. Actually set volume.domain when listing
VM-exposed devices.
QubesOS/qubes-issues#2256
Allow device plugin to list attached and available devices. Enforce
at API level every device being exposed by some domain.
This commit only changes devices API, but not update existing users
(pci) yet.
QubesOS/qubes-issues#2257
