Re: [PATCH] x86/HyperV: correct hv_hcall_page for xen.efi build

[Wei Liu <wl@xxxxxxx>]

On Fri, May 01, 2020 at 01:19:39PM +0100, Andrew Cooper wrote:
> On 01/05/2020 13:17, Wei Liu wrote:
> > On Thu, Apr 30, 2020 at 12:24:15PM +0200, Jan Beulich wrote:
> >> Along the lines of what the not reverted part of 3c4b2eef4941 ("x86:
> >> refine link time stub area related assertion") did, we need to transform
> >> the absolute HV_HCALL_PAGE into the image base relative hv_hcall_page
> >> (or else there'd be no need for two distinct symbols). Otherwise
> >> mkreloc, as used for generating the base relocations of xen.efi, will
> >> spit out warnings like "Difference at .text:0009b74f is 0xc0000000
> >> (expected 0x40000000)". As long as the offending relocations are PC
> >> relative ones, the generated binary is correct afaict, but if there ever
> >> was the absolute address stored, xen.efi would miss a fixup for it.
> >>
> >> Reported-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> >> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
> > Acked-by: Wei Liu <wl@xxxxxxx>
> >
> >> ---
> >> Build tested only (and generated binary inspected) - Wei, please check
> >> that this doesn't break things.
> >>
> > I don't have time to verify this in next couple of weeks, but I will
> > surely notice if there is a breakage.
> 
> FWIW, the resulting assembly is identical, so it surely will be as fine
> as it was previously.

Thanks. That should be okay.

Wei.

> 
> ~Andrew