On Wed, Jul 13, 2016 at 01:00:28PM -0700, Ed Swierk wrote: > On Wed, Jul 13, 2016 at 10:36 AM, Jason Gunthorpe > <jguntho...@obsidianresearch.com> wrote: > > I think your bios is broken? > > The BIOS is broken in many ways. I already have to pass > memmap=256M$0x80000000, otherwise PCIe extended config space > (MMCONFIG) is inaccessible. Also I found memmap=0x7000$0x7a7d0000 > works around "APEI: Can not request [mem 0x7a7d0018-0x7a7d0067] for > APEI ERST registers", as the BIOS seems to be mistakenly reserving > 0x7b7d0000-7b7d7000 instead.
Is it is possible whatever causes the 'reserve RAM buffer' behavior in the kernel is wonky with your BIOS? That seems to be a special Linux action.. Could it be Xen related? The Xen hypervisor replaces the physical ram map for the dom0 guest, which is why you get these sorts of prints: Xen: [mem 0x0000000000000000-0x000000000005ffff] usable and not: [ 0.000000] BIOS-e820: [mem 0x0000000000000000-0x0000000000057fff] usable Jason