[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [PATCH 6/9] target-i386: check/enforce: Check SVM flag supp
From: |
Eduardo Habkost |
Subject: |
[Qemu-devel] [PATCH 6/9] target-i386: check/enforce: Check SVM flag support as well |
Date: |
Fri, 4 Jan 2013 13:37:41 -0200 |
When nested SVM is supported, the kernel returns the SVM flag on
GET_SUPPORTED_CPUID[1], so we can check the SVM flag safely on
kvm_check_features_against_host().
I don't know why the original code ignored the SVM flag. Maybe it was
because kvm_cpu_fill_host() used the CPUID instruction directly instead
of GET_SUPPORTED_CPUID
[1] Older kernels (before v2.6.37) returned the SVM flag even if nested
SVM was _not_ supported. So the only cases where this patch should
change behavior is when SVM is being requested by the user or the
CPU model, but not supported by the host. And on these cases we
really want QEMU to abort if the "enforce" option is set.
Signed-off-by: Eduardo Habkost <address@hidden>
---
Cc: Joerg Roedel <address@hidden>
Cc: address@hidden
Cc: address@hidden
Cc: Jiri Denemark <address@hidden>
I'm CCing libvirt people in case having SVM enabled by default may cause
trouble when libvirt starts using the "enforce" flag. I don't know if
libvirt expects most of the QEMU CPU models to have nested SVM enabled.
---
target-i386/cpu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index 13075c7..21aceed 100644
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -969,7 +969,7 @@ static int kvm_check_features_against_host(x86_def_t
*guest_def)
{&guest_def->ext2_features, &host_def.ext2_features,
~0, ext2_feature_name, 0x80000001, R_EDX},
{&guest_def->ext3_features, &host_def.ext3_features,
- ~CPUID_EXT3_SVM, ext3_feature_name, 0x80000001, R_ECX}};
+ ~0, ext3_feature_name, 0x80000001, R_ECX}};
assert(kvm_enabled());
--
1.7.11.7
- [Qemu-devel] [PATCH 0/9] target-i386: make "enforce" flag work as it should, Eduardo Habkost, 2013/01/04
- [Qemu-devel] [PATCH 2/9] target-i386: kvm: Enable all supported KVM features for -cpu host, Eduardo Habkost, 2013/01/04
- [Qemu-devel] [PATCH 4/9] target-i386: check/enforce: Do not ignore "hypervisor" flag, Eduardo Habkost, 2013/01/04
- [Qemu-devel] [PATCH 5/9] target-i386: check/enforce: Check all CPUID.80000001H.EDX bits, Eduardo Habkost, 2013/01/04
- [Qemu-devel] [PATCH 8/9] target-i386: Call kvm_check_features_against_host() only if CONFIG_KVM is set, Eduardo Habkost, 2013/01/04
- [Qemu-devel] [PATCH 6/9] target-i386: check/enforce: Check SVM flag support as well,
Eduardo Habkost <=
- [Qemu-devel] [PATCH 7/9] target-i386: check/enforce: Eliminate check_feat field, Eduardo Habkost, 2013/01/04
- [Qemu-devel] [PATCH 9/9] target-i386: check/enforce: Check all feature words, Eduardo Habkost, 2013/01/04
- [Qemu-devel] [PATCH 1/9] target-i386: kvm: -cpu host: Use GET_SUPPORTED_CPUID for SVM features, Eduardo Habkost, 2013/01/04
- [Qemu-devel] [PATCH 3/9] target-i386: check/enforce: Fix CPUID leaf numbers on error messages, Eduardo Habkost, 2013/01/04
- Message not available
- Re: [Qemu-devel] [PATCH 0/9] target-i386: make "enforce" flag work as it should, Anthony Liguori, 2013/01/04