Re: [tip:x86/boot] x86/boot/compressed/64: Handle 5-level paging boot if kernel is above 4G

From: Andrei Vagin
Date: Tue Feb 13 2018 - 11:54:06 EST


On Tue, Feb 13, 2018 at 12:02:49PM +0300, Kirill A. Shutemov wrote:
> On Tue, Feb 13, 2018 at 12:41:22AM -0800, Andrei Vagin wrote:
> > On Tue, Feb 13, 2018 at 11:08:16AM +0300, Kirill A. Shutemov wrote:
> > > On Mon, Feb 12, 2018 at 10:51:56PM -0800, Andrei Vagin wrote:
> > > > Hi Kirill,
> > > >
> > > > Something is wrong in this patch.
>
> Could you please check if this makes a difference?

The kernel booted with this patch. Thanks!
https://travis-ci.org/avagin/linux/jobs/341030882

>
> diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
> index 70b30f2bc9e0..99a0e7993252 100644
> --- a/arch/x86/boot/compressed/head_64.S
> +++ b/arch/x86/boot/compressed/head_64.S
> @@ -332,7 +332,7 @@ ENTRY(startup_64)
>
> /* Make sure we have GDT with 32-bit code segment */
> leaq gdt(%rip), %rax
> - movl %eax, gdt64+2(%rip)
> + movq %rax, gdt64+2(%rip)
> lgdt gdt64(%rip)
>
> /*
> --
> Kirill A. Shutemov