Re: [PATCH] x86/boot/64: Initialize 5-level paging variables earlier

From: Kirill A. Shutemov
Date: Tue Oct 13 2020 - 04:20:51 EST


On Tue, Oct 13, 2020 at 10:11:17AM +0200, Borislav Petkov wrote:
> On Mon, Oct 12, 2020 at 11:35:01AM -0400, Arvind Sankar wrote:
> > > qemu supports it. -cpu "qemu64,+la57"
> >
> > Thanks! On QEMU, it does crash without this patch.
>
> Works fine here. I gave this to qemu:
>
> -cpu qemu64,+la57,vendor=GenuineIntel
>
> it said:
>
> qemu-system-x86_64: warning: host doesn't support requested feature: CPUID.07H:ECX.la57 [bit 16]
>
> because host is AMD, probably, and I have
>
> CONFIG_X86_5LEVEL=y
>
> enabled for the guest kernel and tip:x86/seves booted fine.
>
> What am I missing?

With TCG or KVM? I use -machine "type=q35,accel=tcg".

--
Kirill A. Shutemov