On Thu, Jan 03, 2019 at 01:02:47AM +0100, Hans van Kranenburg wrote: > In december, Xen PVH support has been committed in grub master: > https://www.mail-archive.com/grub-devel@gnu.org/msg28125.html > > The last pieces needed in the Linux kernel to boot PVH with grub2 landed > in Linux 4.20. I asked our kernel team to carry those patches on top of > the Linux 4.19 kernel that is going to ship in Buster, and that wish was > granted: > > https://salsa.debian.org/kernel-team/linux/commit/4d63e6ccbbd6081068633b1147e0f77a59379795 > > Please see the commit message in there for an explanation why having the > possibility to boot PVH+grub in Debian Buster out of the box would be great. > > So here's the question: Do you want to help completing the puzzle and > getting a PVH capable grub2 boot image in the grub-xen-* packages in Buster?
I think I'm OK with cherry-picking the relevant patch stack. Presumably this would need to be in new grub-xen-pvh-bin / grub-xen-pvh binary packages, as is usual for separate platform builds? > Now, I create a grub.cfg file and then... > > ./grub-mkstandalone --grub-mkimage=./grub-mkimage -o > grub-i386-xen_pvh.bin -O i386-xen_pvh -d grub-core/ > boot/grub/grub.cfg=grub.cfg > > ...I end up with something that I can use as kernel image for the Xen > PVH virtual machine. Can you elaborate on what you mean by "use as kernel image for the Xen PVH virtual machine"? In other words, what does the process of installing a boot loader in a PVH guest look like? The current code in upstream grub-install essentially just does a grub-mkimage but doesn't have any platform-dependent install steps. If you run upstream grub-install, are you then just supposed to write 'kernel = "/boot/grub/i386-xen_pvh/core.elf"' in your guest configuration file? In PVH mode, is the file name referenced via "kernel" loaded from the dom0's filesystem or the domU's? (Compare https://salsa.debian.org/grub-team/grub/blob/master/debian/patches/grub-install-pvxen-paths.patch which we carry for PV guests, although I gather PVH is sufficiently different that the same approach probably doesn't work.) -- Colin Watson [cjwat...@debian.org]
