From: Eduardo Habkost <ehabkost@redhat.com>
To: "Michael S. Tsirkin" <mst@redhat.com>, qemu-devel@nongnu.org
Cc: Richard Henderson <rth@twiddle.net>, Igor Mammedov <imammedo@redhat.com>
Subject: [Qemu-devel] [PATCH] pc: Use "min-[x]level" on compat_props
Date: Mon, 5 Jun 2017 12:56:55 -0300 [thread overview]
Message-ID: <20170605155655.19315-1-ehabkost@redhat.com> (raw)
Since the automatic cpuid-level code was introduced in commit
c39c0edf9bb3b968ba95484465a50c7b19f4aa3a, the CPU model tables just
define the default CPUID level code (set using "min-level"). Setting
"[x]level" forces CPUID level to a specific value and disable the
automatic-level logic.
But the PC compat code was not updated and the existing "[x]level"
compat properties broke compatibility for people using features that
triggered the auto-level code. To keep previous behavior, we should set
"min-[x]level" instead of "[x]level" on compat_props.
This was not a problem for most cases, because old machine-types don't
have full-cpuid-auto-level enabled. The only common use case it broke
was the CPUID[7] auto-level code, that was already enabled since the
first CPUID[7] feature was introduced (in QEMU 1.4.0).
This causes the regression reported at:
https://bugzilla.redhat.com/show_bug.cgi?id=1454641
Change the PC compat code to use "min-[x]level" instead of "[x]level" on
compat_props, and add new test cases to ensure we don't break this
again.
Reported-by: "Guo, Zhiyi" <zhguo@redhat.com>
Signd-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
include/hw/i386/pc.h | 42 +++++++++++++++++++++---------------------
tests/test-x86-cpuid-compat.c | 38 ++++++++++++++++++++++++++++++++++++++
2 files changed, 59 insertions(+), 21 deletions(-)
diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index e447f5d8f4..d071c9c0e9 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -566,75 +566,75 @@ bool e820_get_entry(int, uint32_t, uint64_t *, uint64_t *);
.value = "off",\
},{\
.driver = "qemu64" "-" TYPE_X86_CPU,\
- .property = "level",\
+ .property = "min-level",\
.value = stringify(4),\
},{\
.driver = "kvm64" "-" TYPE_X86_CPU,\
- .property = "level",\
+ .property = "min-level",\
.value = stringify(5),\
},{\
.driver = "pentium3" "-" TYPE_X86_CPU,\
- .property = "level",\
+ .property = "min-level",\
.value = stringify(2),\
},{\
.driver = "n270" "-" TYPE_X86_CPU,\
- .property = "level",\
+ .property = "min-level",\
.value = stringify(5),\
},{\
.driver = "Conroe" "-" TYPE_X86_CPU,\
- .property = "level",\
+ .property = "min-level",\
.value = stringify(4),\
},{\
.driver = "Penryn" "-" TYPE_X86_CPU,\
- .property = "level",\
+ .property = "min-level",\
.value = stringify(4),\
},{\
.driver = "Nehalem" "-" TYPE_X86_CPU,\
- .property = "level",\
+ .property = "min-level",\
.value = stringify(4),\
},{\
.driver = "n270" "-" TYPE_X86_CPU,\
- .property = "xlevel",\
+ .property = "min-xlevel",\
.value = stringify(0x8000000a),\
},{\
.driver = "Penryn" "-" TYPE_X86_CPU,\
- .property = "xlevel",\
+ .property = "min-xlevel",\
.value = stringify(0x8000000a),\
},{\
.driver = "Conroe" "-" TYPE_X86_CPU,\
- .property = "xlevel",\
+ .property = "min-xlevel",\
.value = stringify(0x8000000a),\
},{\
.driver = "Nehalem" "-" TYPE_X86_CPU,\
- .property = "xlevel",\
+ .property = "min-xlevel",\
.value = stringify(0x8000000a),\
},{\
.driver = "Westmere" "-" TYPE_X86_CPU,\
- .property = "xlevel",\
+ .property = "min-xlevel",\
.value = stringify(0x8000000a),\
},{\
.driver = "SandyBridge" "-" TYPE_X86_CPU,\
- .property = "xlevel",\
+ .property = "min-xlevel",\
.value = stringify(0x8000000a),\
},{\
.driver = "IvyBridge" "-" TYPE_X86_CPU,\
- .property = "xlevel",\
+ .property = "min-xlevel",\
.value = stringify(0x8000000a),\
},{\
.driver = "Haswell" "-" TYPE_X86_CPU,\
- .property = "xlevel",\
+ .property = "min-xlevel",\
.value = stringify(0x8000000a),\
},{\
.driver = "Haswell-noTSX" "-" TYPE_X86_CPU,\
- .property = "xlevel",\
+ .property = "min-xlevel",\
.value = stringify(0x8000000a),\
},{\
.driver = "Broadwell" "-" TYPE_X86_CPU,\
- .property = "xlevel",\
+ .property = "min-xlevel",\
.value = stringify(0x8000000a),\
},{\
.driver = "Broadwell-noTSX" "-" TYPE_X86_CPU,\
- .property = "xlevel",\
+ .property = "min-xlevel",\
.value = stringify(0x8000000a),\
},{\
.driver = TYPE_X86_CPU,\
@@ -860,7 +860,7 @@ bool e820_get_entry(int, uint32_t, uint64_t *, uint64_t *);
.value = stringify(2),\
},{\
.driver = "Conroe-" TYPE_X86_CPU,\
- .property = "level",\
+ .property = "min-level",\
.value = stringify(2),\
},{\
.driver = "Penryn-" TYPE_X86_CPU,\
@@ -868,7 +868,7 @@ bool e820_get_entry(int, uint32_t, uint64_t *, uint64_t *);
.value = stringify(2),\
},{\
.driver = "Penryn-" TYPE_X86_CPU,\
- .property = "level",\
+ .property = "min-level",\
.value = stringify(2),\
},{\
.driver = "Nehalem-" TYPE_X86_CPU,\
@@ -876,7 +876,7 @@ bool e820_get_entry(int, uint32_t, uint64_t *, uint64_t *);
.value = stringify(2),\
},{\
.driver = "Nehalem-" TYPE_X86_CPU,\
- .property = "level",\
+ .property = "min-level",\
.value = stringify(2),\
},{\
.driver = "virtio-net-pci",\
diff --git a/tests/test-x86-cpuid-compat.c b/tests/test-x86-cpuid-compat.c
index 6c71e46391..652216f531 100644
--- a/tests/test-x86-cpuid-compat.c
+++ b/tests/test-x86-cpuid-compat.c
@@ -313,6 +313,44 @@ int main(int argc, char **argv)
add_cpuid_test("x86/cpuid/auto-xlevel2/pc-2.7",
"-machine pc-i440fx-2.7 -cpu 486,+xstore",
"xlevel2", 0);
+ /*
+ * QEMU 1.4.0 had auto-level enabled for CPUID[7], already,
+ * and the compat code that sets default level shouldn't
+ * disable the auto-level=7 code:
+ */
+ add_cpuid_test("x86/cpuid/auto-level7/pc-i440fx-1.4/off",
+ "-machine pc-i440fx-1.4 -cpu Nehalem",
+ "level", 2);
+ add_cpuid_test("x86/cpuid/auto-level7/pc-i440fx-1.5/on",
+ "-machine pc-i440fx-1.4 -cpu Nehalem,+smap",
+ "level", 7);
+ add_cpuid_test("x86/cpuid/auto-level7/pc-i440fx-2.3/off",
+ "-machine pc-i440fx-2.3 -cpu Penryn",
+ "level", 4);
+ add_cpuid_test("x86/cpuid/auto-level7/pc-i440fx-2.3/on",
+ "-machine pc-i440fx-2.3 -cpu Penryn,+erms",
+ "level", 7);
+ add_cpuid_test("x86/cpuid/auto-level7/pc-i440fx-2.9/off",
+ "-machine pc-i440fx-2.9 -cpu Conroe",
+ "level", 10);
+ add_cpuid_test("x86/cpuid/auto-level7/pc-i440fx-2.9/on",
+ "-machine pc-i440fx-2.9 -cpu Conroe,+erms",
+ "level", 10);
+
+ /*
+ * xlevel don't have any feature that triggers auto-level
+ * code on old machine-types. Just check if the compat code
+ * is working correctly:
+ */
+ add_cpuid_test("x86/cpuid/xlevel-compat/pc-i440fx-2.3",
+ "-machine pc-i440fx-2.3 -cpu SandyBridge",
+ "xlevel", 0x8000000a);
+ add_cpuid_test("x86/cpuid/xlevel-compat/pc-i440fx-2.4/npt-off",
+ "-machine pc-i440fx-2.4 -cpu SandyBridge,",
+ "xlevel", 0x80000008);
+ add_cpuid_test("x86/cpuid/xlevel-compat/pc-i440fx-2.4/npt-on",
+ "-machine pc-i440fx-2.4 -cpu SandyBridge,+npt",
+ "xlevel", 0x80000008);
/* Test feature parsing */
add_feature_test("x86/cpuid/features/plus",
--
2.11.0.259.g40922b1
next reply other threads:[~2017-06-05 15:57 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-06-05 15:56 Eduardo Habkost [this message]
2017-06-05 16:07 ` [Qemu-devel] [PATCH] pc: Use "min-[x]level" on compat_props Michael S. Tsirkin
2017-06-05 18:47 ` Eduardo Habkost
2017-06-05 17:36 ` Eduardo Habkost
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