On Sun, May 30, 2021 at 11:06:18AM -0400, Tianyu Lan wrote: > From: Tianyu Lan <Tianyu.Lan@xxxxxxxxxxxxx> > > Hyper-V exposes GHCB page via SEV ES GHCB MSR for SNP guest > to communicate with hypervisor. Map GHCB page for all > cpus to read/write MSR register and submit hvcall request > via GHCB. > > Signed-off-by: Tianyu Lan <Tianyu.Lan@xxxxxxxxxxxxx> > --- > arch/x86/hyperv/hv_init.c | 60 ++++++++++++++++++++++++++++++--- > arch/x86/include/asm/mshyperv.h | 2 ++ > include/asm-generic/mshyperv.h | 2 ++ > 3 files changed, 60 insertions(+), 4 deletions(-) > > diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c > index bb0ae4b5c00f..dc74d01cb859 100644 > --- a/arch/x86/hyperv/hv_init.c > +++ b/arch/x86/hyperv/hv_init.c > @@ -60,6 +60,9 @@ static int hv_cpu_init(unsigned int cpu) > struct hv_vp_assist_page **hvp = &hv_vp_assist_page[smp_processor_id()]; > void **input_arg; > struct page *pg; > + u64 ghcb_gpa; > + void *ghcb_va; > + void **ghcb_base; Any reason you can't reuse the SEV-ES support code in the Linux kernel? It already has code to setup GHCBs for all vCPUs. I see that you don't need #VC handling in your SNP VMs because of the paravisor running underneath it, but just re-using the GHCB setup code shouldn't be too hard. Regards, Joerg
