Balloon driver scrub memory page before giving it back to the
hypervisor. Normally this is a good thing, to avoid leaking VM's memory
data into Xen and other domains. But during initial startup when maxmem
is bigger than initial memory, on HVM and PVH, Populate-on-Demand (PoD) is in use.
This means every page on initial balloon down needs to be first mapped
by Xen into VM's memory (as it wasn't populated before - and in fact
didn't have any data), scrubbed by the kernel and then given back to
Xen. This is great waste of time. Such operation with default settings
(initial memory 400M, maxmem 4000M) can take few seconds, delaying every
VM startup (including DispVM). In extreme situation, when running inside
nested virtualization, the effect is much worse.
Avoid this problem by disabling memory scrubbing during initial boot,
and re-enable it as soon as user space kicks in - in initramfs, before
mounting root filesystem, to be sure it's enabled before memory contains
any kind of secrets.
This commit handle only one case - when kernel in managed by the VM
itself. It is critical to enable initramfs module whenever
xen_scrub_pages=0 kernel option is given, so make them depend on the
same condition and ship them in the same package.
FixesQubesOS/qubes-issues#1963
Don't rely on python -> python2 symlink and default %{python_*} macros.
Add explicit BR: gcc (default build env for fc29 doesn't have it
anymore).
QubesOS/qubes-issues#4223
When root device is available read-write (TemplateVM/StandaloneVM), its
mounted directly, instead of using device-mapper layer. But
/dev/mapper/dmroot still needs to exists (it is pointed from
/etc/fstab), otherwise various tools, including grub-mkconfig get
confused.
Create a symlink using udev rule. It is already done in initramfs, and
in case of Fedora that udev rule/symlink survive switching to
non-initramfs udev, but not on Debian. So, add appropriate udev rules
file.
FixesQubesOS/qubes-issues#3178
This package is responsible for kernel modules and initramfs additions
needed in Qubes VM. When installed, it is possible to switch the VM to
use PV Grub and load the kernel from inside of VM. This greatly ease
installing custom kernel modules.
Changes:
- make qubes_cow_setup.sh working with both dracut and initramfs-tools
- add initramfs-tools configuration/scripts (including
qubes_cow_setup.sh)
- modify DESTDIR to handle multiple binary packages out of single
source
QubesOS/qubes-issues#1354
When PV Grub will be used, VM initramfs should not contain /lib/modules
mounting code, as the VM root.img will already contains kernel modules.
Make it possible by splitting the module.
QubesOS/qubes-issues#1354
This is preparation for pvgrub support, where all VM kernel files will
be installed inside of VM instead of dom0.
But also the same could be used to prepare VM kernel image from any dom0
kernel.
We have no control over package installation, so it can happen to be
before qubes-release got installed. Simply enable both dom0 and VM
services - they contains relevant start conditions.
