[PATCH 3/9] x86/hyperv: Mark Hyper-V vp assist page unencrypted in SEV-SNP enlightened guest

Tianyu Lan
2023-06-01T15:16:51Z

From: Tianyu Lan <tiala@microsoft.com>

hv vp assist page needs to be shared between SEV-SNP guest and Hyper-V.
So mark the page unencrypted in the SEV-SNP guest.

Signed-off-by: Tianyu Lan <tiala@microsoft.com>
---
arch/x86/hyperv/hv_init.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index b4a2327c823b..331b855314b7 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -18,6 +18,7 @@
#include <asm/hyperv-tlfs.h>
#include <asm/mshyperv.h>
#include <asm/idtentry.h>
+#include <asm/set_memory.h>
#include <linux/kexec.h>
#include <linux/version.h>
#include <linux/vmalloc.h>
@@ -113,6 +114,11 @@ static int hv_cpu_init(unsigned int cpu)

}
if (!WARN_ON(!(*hvp))) {
+ if (hv_isolation_type_en_snp()) {
+ WARN_ON_ONCE(set_memory_decrypted((unsigned long)(*hvp), 1));
+ memset(*hvp, 0, PAGE_SIZE);
+ }
+
msr.enable = 1;
wrmsrl(HV_X64_MSR_VP_ASSIST_PAGE, msr.as_uint64);
}
--
2.25.1