File 0074-cpu-i386-populate-CPUID-0x8000_001F.patch of Package qemu

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File 0074-cpu-i386-populate-CPUID-0x8000_001F.patch of Package qemu (Revision 08acdc2fe7a9ecf7efb70cf7d4b7d845)

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From 28839121aa98b7e126a7770200041203acd077bb Mon Sep 17 00:00:00 2001
From: Brijesh Singh <brijesh.singh@amd.com>
Date: Thu, 15 Feb 2018 09:03:25 -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>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
[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 70c8ae82d5..a7e27f3bbf 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -23,6 +23,7 @@
 #include "exec/exec-all.h"
 #include "sysemu/kvm.h"
 #include "sysemu/cpus.h"
+#include "sysemu/sev.h"
 #include "kvm_i386.h"
 
 #include "qemu/error-report.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 0074-cpu-i386-populate-CPUID-0x8000_001F.patch of Package qemu (Revision 08acdc2fe7a9ecf7efb70cf7d4b7d845)

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