Re: [PATCH v2 08/12] x86/sev: Park APs on AP Jump Table with GHCB protocol version 2

Joerg Roedel
2022-01-27T09:01:41Z

On Fri, Nov 12, 2021 at 05:33:05PM +0100, Borislav Petkov wrote:
> On Mon, Sep 13, 2021 at 05:55:59PM +0200, Joerg Roedel wrote:
> > + "ljmpl *%0" : :
> > + "m" (real_mode_header->sev_real_ap_park_asm),
> > + "b" (sev_es_jump_table_pa >> 4));
>
> In any case, this asm needs comments: why those regs, why
> sev_es_jump_table_pa >> 4 in rbx (I found later in the patch why) and so
> on.

Turned out the jump_table_pa is not used in asm code anymore. It was a
left-over from a previous version of the patch, it is removed now.

> > +SYM_INNER_LABEL(sev_ap_park_paging_off, SYM_L_GLOBAL)
>
> Global symbol but used only in this file. .L-prefix then?

It needs to be a global symbol so the pa_ variant can be generated.

Regards,

--
Jörg Rödel
jroedel@suse.de

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