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But the fact that it supports both interfaces > means that the GHCB page based logic is pulled into the early startup > code where PA to VA conversions are problematic, given that it runs from > the 1:1 mapping of memory. > > So keep snp_cpuid() itself in the startup code, but factor out the > hypervisor calls via a callback, so that the GHCB page handling can be > moved out. > > Code refactoring only - no functional change intended. > > Signed-off-by: Ard Biesheuvel Reviewed-by: Tom Lendacky Just a minor comment below... > --- > arch/x86/boot/startup/sev-shared.c | 60 ++++---------------- > arch/x86/coco/sev/vc-shared.c | 49 +++++++++++++++- > arch/x86/include/asm/sev.h | 3 +- > 3 files changed, 61 insertions(+), 51 deletions(-) > > diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h > index 89075ff19afa..2cabf617de3c 100644 > --- a/arch/x86/include/asm/sev.h > +++ b/arch/x86/include/asm/sev.h > @@ -552,7 +552,8 @@ struct cpuid_leaf { > u32 edx; > }; > > -int snp_cpuid(struct ghcb *ghcb, struct es_em_ctxt *ctxt, struct cpuid_leaf *leaf); > +int snp_cpuid(void (*cpuid_hv)(void *ctx, struct cpuid_leaf *), You use cpuid_fn elsewhere in the patch. I'm ok with either one, but they should match name-wise. Also, you should provide an argument name for the leaf pointer or no argument name for the void pointer (throughout). Thanks, Tom > + void *ctx, struct cpuid_leaf *leaf); > > void __noreturn sev_es_terminate(unsigned int set, unsigned int reason); > enum es_result sev_es_ghcb_hv_call(struct ghcb *ghcb,