File 0060-cpu-i386-populate-CPUID-0x8000_001F.patch of Package qemu-linux-user.9686

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File 0060-cpu-i386-populate-CPUID-0x8000_001F.patch of Package qemu-linux-user.9686 (Revision b9fbe18333659bc1e0f571a87abf1a80)

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From c67ef2f30b04823ca206320bbce0efb220a1889d Mon Sep 17 00:00:00 2001
From: Brijesh Singh <brijesh.singh@amd.com>
Date: Thu, 8 Mar 2018 06:48:58 -0600
Subject: [PATCH] cpu/i386: populate CPUID 0x8000_001F when SEV is active

When SEV is enabled, CPUID 0x8000_001F should provide additional
information regarding the feature (such as which page table bit is used
to mark the pages as encrypted etc).

The details for memory encryption CPUID is available in AMD APM
(https://support.amd.com/TechDocs/24594.pdf) Section E.4.17

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit 6cb8f2a663a47c6e0da17fc4fb9e06abfda2bd48)
[BR: FATE#322124]
Signed-off-by: Bruce Rogers <brogers@suse.com>
---
 target/i386/cpu.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 1acf300cf8..4cc30bc0df 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -24,6 +24,7 @@
 #include "sysemu/kvm.h"
 #include "sysemu/cpus.h"
 #include "kvm_i386.h"
+#include "sev_i386.h"
 
 #include "qemu/error-report.h"
 #include "qemu/option.h"
@@ -3578,6 +3579,13 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
         *ecx = 0;
         *edx = 0;
         break;
+    case 0x8000001F:
+        *eax = sev_enabled() ? 0x2 : 0;
+        *ebx = sev_get_cbit_position();
+        *ebx |= sev_get_reduced_phys_bits() << 6;
+        *ecx = 0;
+        *edx = 0;
+        break;
     default:
         /* reserved values: zero */
         *eax = 0;
@@ -4000,6 +4008,11 @@ static void x86_cpu_expand_features(X86CPU *cpu, Error **errp)
         if (env->features[FEAT_8000_0001_ECX] & CPUID_EXT3_SVM) {
             x86_cpu_adjust_level(cpu, &env->cpuid_min_xlevel, 0x8000000A);
         }
+
+        /* SEV requires CPUID[0x8000001F] */
+        if (sev_enabled()) {
+            x86_cpu_adjust_level(cpu, &env->cpuid_min_xlevel, 0x8000001F);
+        }
     }
 
     /* Set cpuid_*level* based on cpuid_min_*level, if not explicitly set */

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File 0060-cpu-i386-populate-CPUID-0x8000_001F.patch of Package qemu-linux-user.9686 (Revision b9fbe18333659bc1e0f571a87abf1a80)

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