On 20/11/2017 09:55, Juergen Gross wrote: > On 20/11/17 10:51, Roger Pau Monné wrote: >> Adding xen-devel, dropped it on my reply. >> >> Replying from my phone, sorry for the formatting. >> >> >> El 20 nov. 2017 9:35, "Juergen Gross" <jgr...@suse.com >> <mailto:jgr...@suse.com>> escribió: >> >> For PVH domains loading of the ACPI RSDP table is done via >> allocating >> a domain loader segment after having loaded the kernel. This >> leads to >> the RSDP table being loaded at an arbitrary guest address instead of >> the architectural correct address just below 1MB. >> >> >> AFAIK this is only true for legacy BIOS boot, when using UEFI the >> RSDP can be anywhere in memory, hence grub2 must already have an >> alternative way of finding the RSDP apart from scanning the low 1MB. > The problem isn't grub2, but the loaded linux kernel. Without this > patch Linux won't find the RSDP when booted in a PVH domain via grub2. > > I could modify grub2 even further to move the RSDP to the correct > address, but I think doing it correctly on Xen side is the better > option.
Why? The PVH info block contains a pointer directly to the RSDP, and Linux should be following this rather than scanning for it using the legacy method. ~Andrew _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org https://lists.xen.org/xen-devel
