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| author |   Nadav Amit <namit@cs.technion.ac.il> | 2014-07-15 17:37:46 +0300 |
|---|---|---|
| committer |   Paolo Bonzini <pbonzini@redhat.com> | 2014-07-21 17:17:52 +0200 |
| commit | 6f43ed01e87c8a8dbd8c826eaf0f714c1342c039 (patch) | |
| tree | 96064816637d154889b1b4bea5e6c5dd6062c9bf /arch/x86/include | |
| parent | KVM: nVMX: clean up nested_release_vmcs12 and code around it (diff) | |
| download | linux-dev-6f43ed01e87c8a8dbd8c826eaf0f714c1342c039.tar.xz linux-dev-6f43ed01e87c8a8dbd8c826eaf0f714c1342c039.zip | |
KVM: x86: DR6/7.RTM cannot be written
Haswell and newer Intel CPUs have support for RTM, and in that case DR6.RTM is
not fixed to 1 and DR7.RTM is not fixed to zero. That is not the case in the
current KVM implementation. This bug is apparent only if the MOV-DR instruction
is emulated or the host also debugs the guest.
This patch is a partial fix which enables DR6.RTM and DR7.RTM to be cleared and
set respectively. It also sets DR6.RTM upon every debug exception. Obviously,
it is not a complete fix, as debugging of RTM is still unsupported.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/include')
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index b8a4480176b9..a84eaf7ba33f 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -152,14 +152,16 @@ enum { #define DR6_BD (1 << 13) #define DR6_BS (1 << 14) -#define DR6_FIXED_1 0xffff0ff0 -#define DR6_VOLATILE 0x0000e00f +#define DR6_RTM (1 << 16) +#define DR6_FIXED_1 0xfffe0ff0 +#define DR6_INIT 0xffff0ff0 +#define DR6_VOLATILE 0x0001e00f #define DR7_BP_EN_MASK 0x000000ff #define DR7_GE (1 << 9) #define DR7_GD (1 << 13) #define DR7_FIXED_1 0x00000400 -#define DR7_VOLATILE 0xffff23ff +#define DR7_VOLATILE 0xffff2bff /* apic attention bits */ #define KVM_APIC_CHECK_VAPIC 0 |