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Blame SOURCES/kvm-target-i386-kvm_cpu_fill_host-No-need-to-check-xleve.patch

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From f51c618ce3598d9a6a3256e4dd2b9dd3164fbc81 Mon Sep 17 00:00:00 2001
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From: Eduardo Habkost <ehabkost@redhat.com>
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Date: Thu, 23 Feb 2017 14:29:36 +0100
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Subject: [PATCH 06/17] target-i386: kvm_cpu_fill_host(): No need to check
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 xlevel2
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RH-Author: Eduardo Habkost <ehabkost@redhat.com>
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Message-id: <20170223142945.17790-6-ehabkost@redhat.com>
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Patchwork-id: 74036
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O-Subject: [RHEL-7.4 qemu-kvm PATCH v2 05/14] target-i386: kvm_cpu_fill_host(): No need to check xlevel2
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Bugzilla: 1382122
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RH-Acked-by: Paolo Bonzini <pbonzini@redhat.com>
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RH-Acked-by: Igor Mammedov <imammedo@redhat.com>
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RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
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There's no need to check CPU xlevel2 before calling
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kvm_arch_get_supported_cpuid(s, 0xC0000001, 0, R_EDX), because:
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 * The kernel won't return any entry for 0xC0000000 if host CPU vendor
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   is not Centaur (See kvm_dev_ioctl_get_supported_cpuid() on the kernel
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   code)
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 * Similarly, the kernel won't return any entry for 0xC0000001 if
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   CPUID[0xC0000000].EAX is < 0xC0000001
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 * kvm_arch_get_supported_cpuid() will return 0 if no entry is returned
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   by the kernel for the requested leaf
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For similar reasons, we can simply set x86_cpu_def->xlevel2 directly
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instead of making it conditional, because it will be set to 0 CPU vendor
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is not Centaur.
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This will simplify the kvm_cpu_fill_host() code a little.
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Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
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[Remove unparseable comment. - Paolo]
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Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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(cherry picked from commit 803a932706e3ba335d4c98f3577a05cb000f1699)
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Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
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Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
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---
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 target-i386/cpu.c | 11 ++++-------
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 1 file changed, 4 insertions(+), 7 deletions(-)
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diff --git a/target-i386/cpu.c b/target-i386/cpu.c
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index a10055b..02bd038 100644
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--- a/target-i386/cpu.c
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+++ b/target-i386/cpu.c
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@@ -1285,13 +1285,10 @@ static void kvm_cpu_fill_host(x86_def_t *x86_cpu_def)
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     cpu_x86_fill_model_id(x86_cpu_def->model_id);
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     /* Call Centaur's CPUID instruction. */
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-    eax = kvm_arch_get_supported_cpuid(s, 0xC0000000, 0, R_EAX);
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-    if (eax >= 0xC0000001) {
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-        /* Support VIA max extended level */
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-        x86_cpu_def->xlevel2 = eax;
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-        x86_cpu_def->features[FEAT_C000_0001_EDX] =
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-                kvm_arch_get_supported_cpuid(s, 0xC0000001, 0, R_EDX);
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-    }
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+    x86_cpu_def->xlevel2 =
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+        kvm_arch_get_supported_cpuid(s, 0xC0000000, 0, R_EAX);
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+    x86_cpu_def->features[FEAT_C000_0001_EDX] =
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+        kvm_arch_get_supported_cpuid(s, 0xC0000001, 0, R_EDX);
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     /* Other KVM-specific feature fields: */
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     x86_cpu_def->features[FEAT_SVM] =
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-- 
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1.8.3.1
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