[RFC,V6,06/14] x86/hyperv: Mark Hyper-V vp assist page unencrypted in SEV-SNP enlightened guest

Message ID 20230515165917.1306922-7-ltykernel@gmail.com
State New
Headers
Series x86/hyperv/sev: Add AMD sev-snp enlightened guest support on hyperv |

Commit Message

Tianyu Lan May 15, 2023, 4:59 p.m. UTC
  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(+)
  

Patch

diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index a5f9474f08e1..9f3e2d71d015 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);
 	}