Blame SOURCES/kvm-i386-Disable-OSPKE-on-Cascadelake-Server.patch

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From b082e420af608c6b060e29e392e0a7fa0655298d Mon Sep 17 00:00:00 2001
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From: Eduardo Habkost <ehabkost@redhat.com>
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Date: Thu, 3 Oct 2019 22:12:16 +0200
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Subject: [PATCH 2/4] i386: Disable OSPKE on Cascadelake-Server
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RH-Author: Eduardo Habkost <ehabkost@redhat.com>
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Message-id: <20191003221217.8527-3-ehabkost@redhat.com>
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Patchwork-id: 90953
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O-Subject: [RHEL-7.8 qemu-kvm PATCH 2/3] i386: Disable OSPKE on Cascadelake-Server
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Bugzilla: 1638471
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RH-Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
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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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This is a partial cherry pick of upstream commit:
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commit bb4928c7cafe50ab2137a0034e350ef1bfa044d9
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Author: Eduardo Habkost <ehabkost@redhat.com>
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Date:   Tue Mar 19 17:05:15 2019 -0300
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    i386: Disable OSPKE on CPU model definitions
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    Currently, the Cascadelake-Server, Icelake-Client, and
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    Icelake-Server are always generating the following warning:
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      qemu-system-x86_64: warning: \
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        host doesn't support requested feature: CPUID.07H:ECX [bit 4]
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    This happens because OSPKE was never returned by
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    GET_SUPPORTED_CPUID or x86_cpu_get_supported_feature_word().
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    OSPKE is a runtime flag automatically set by the KVM module or by
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    TCG code, was always cleared by x86_cpu_filter_features(), and
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    was not supposed to appear on the CPU model table.
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    Remove the OSPKE flag from the CPU model table entries, to avoid
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    the bogus warning and avoid returning invalid feature data on
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    query-cpu-* QMP commands.  As OSPKE was always cleared by
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    x86_cpu_filter_features(), this won't have any guest-visible
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    impact.
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    Include a test case that should detect the problem if we introduce
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    a similar bug again.
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    Fixes: c7a88b52f62b ("i386: Add new model of Cascadelake-Server")
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    Fixes: 8a11c62da914 ("i386: Add new CPU model Icelake-{Server,Client}")
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    Cc: Tao Xu <tao3.xu@intel.com>
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    Cc: Robert Hoo <robert.hu@linux.intel.com>
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    Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
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    Message-Id: <20190319200515.14999-1-ehabkost@redhat.com>
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    Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
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It includes only the Cascadelake-Server change, because Icelake*
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is not present in the RHEL7 tree.
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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 | 2 +-
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 1 file changed, 1 insertion(+), 1 deletion(-)
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diff --git a/target-i386/cpu.c b/target-i386/cpu.c
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index 5b988c9..926373b 100644
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--- a/target-i386/cpu.c
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+++ b/target-i386/cpu.c
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@@ -1531,7 +1531,7 @@ static x86_def_t builtin_x86_defs[] = {
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             CPUID_7_0_EBX_AVX512VL | CPUID_7_0_EBX_CLFLUSHOPT |
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             CPUID_7_0_EBX_INTEL_PT,
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         .features[FEAT_7_0_ECX] =
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-            CPUID_7_0_ECX_PKU | CPUID_7_0_ECX_OSPKE |
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+            CPUID_7_0_ECX_PKU |
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             CPUID_7_0_ECX_AVX512VNNI,
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         .features[FEAT_7_0_EDX] =
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             CPUID_7_0_EDX_SPEC_CTRL | CPUID_7_0_EDX_SPEC_CTRL_SSBD,
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-- 
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1.8.3.1
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