* [PATCH 0/3] KVM: VMX: Clean up RTIT MAXPHYADDR usage
@ 2020-07-16 3:44 Sean Christopherson
2020-07-16 3:44 ` [PATCH 1/3] KVM: VMX: Use precomputed MAXPHYADDR for RTIT base MSR check Sean Christopherson
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: Sean Christopherson @ 2020-07-16 3:44 UTC (permalink / raw)
To: Paolo Bonzini
Cc: Sean Christopherson, Vitaly Kuznetsov, Wanpeng Li, Jim Mattson,
Joerg Roedel, kvm, linux-kernel
Stop using cpuid_query_maxphyaddr() for a random RTIT MSR check and
unexport said function to discourage future use.
Sean Christopherson (3):
KVM: VMX: Use precomputed MAXPHYADDR for RTIT base MSR check
KVM: VMX: Replace MSR_IA32_RTIT_OUTPUT_BASE_MASK with helper function
KVM: x86: Unexport cpuid_query_maxphyaddr()
arch/x86/kvm/cpuid.c | 1 -
arch/x86/kvm/vmx/vmx.c | 11 +++++++----
2 files changed, 7 insertions(+), 5 deletions(-)
--
2.26.0
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH 1/3] KVM: VMX: Use precomputed MAXPHYADDR for RTIT base MSR check
2020-07-16 3:44 [PATCH 0/3] KVM: VMX: Clean up RTIT MAXPHYADDR usage Sean Christopherson
@ 2020-07-16 3:44 ` Sean Christopherson
2020-07-16 3:44 ` [PATCH 2/3] KVM: VMX: Replace MSR_IA32_RTIT_OUTPUT_BASE_MASK with helper function Sean Christopherson
2020-07-16 3:44 ` [PATCH 3/3] KVM: x86: Unexport cpuid_query_maxphyaddr() Sean Christopherson
2 siblings, 0 replies; 4+ messages in thread
From: Sean Christopherson @ 2020-07-16 3:44 UTC (permalink / raw)
To: Paolo Bonzini
Cc: Sean Christopherson, Vitaly Kuznetsov, Wanpeng Li, Jim Mattson,
Joerg Roedel, kvm, linux-kernel
Use cpuid_maxphyaddr() instead of cpuid_query_maxphyaddr() for the
RTIT base MSR check. There is no reason to recompute MAXPHYADDR as the
precomputed version is synchronized with CPUID updates, and
MSR_IA32_RTIT_OUTPUT_BASE is not written between stuffing CPUID and
refreshing vcpu->arch.maxphyaddr.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
arch/x86/kvm/vmx/vmx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 1bb59ae5016dc..50b7e85d37352 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -146,7 +146,7 @@ module_param_named(preemption_timer, enable_preemption_timer, bool, S_IRUGO);
RTIT_STATUS_BYTECNT))
#define MSR_IA32_RTIT_OUTPUT_BASE_MASK \
- (~((1UL << cpuid_query_maxphyaddr(vcpu)) - 1) | 0x7f)
+ (~((1UL << cpuid_maxphyaddr(vcpu)) - 1) | 0x7f)
/*
* These 2 parameters are used to config the controls for Pause-Loop Exiting:
--
2.26.0
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH 2/3] KVM: VMX: Replace MSR_IA32_RTIT_OUTPUT_BASE_MASK with helper function
2020-07-16 3:44 [PATCH 0/3] KVM: VMX: Clean up RTIT MAXPHYADDR usage Sean Christopherson
2020-07-16 3:44 ` [PATCH 1/3] KVM: VMX: Use precomputed MAXPHYADDR for RTIT base MSR check Sean Christopherson
@ 2020-07-16 3:44 ` Sean Christopherson
2020-07-16 3:44 ` [PATCH 3/3] KVM: x86: Unexport cpuid_query_maxphyaddr() Sean Christopherson
2 siblings, 0 replies; 4+ messages in thread
From: Sean Christopherson @ 2020-07-16 3:44 UTC (permalink / raw)
To: Paolo Bonzini
Cc: Sean Christopherson, Vitaly Kuznetsov, Wanpeng Li, Jim Mattson,
Joerg Roedel, kvm, linux-kernel
Replace the subtly not-a-constant MSR_IA32_RTIT_OUTPUT_BASE_MASK with a
proper helper function to check whether or not the specified base is
valid. Blindly referencing the local 'vcpu' is especially nasty.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
arch/x86/kvm/vmx/vmx.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 50b7e85d37352..cf3c3562e843c 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -145,9 +145,6 @@ module_param_named(preemption_timer, enable_preemption_timer, bool, S_IRUGO);
RTIT_STATUS_ERROR | RTIT_STATUS_STOPPED | \
RTIT_STATUS_BYTECNT))
-#define MSR_IA32_RTIT_OUTPUT_BASE_MASK \
- (~((1UL << cpuid_maxphyaddr(vcpu)) - 1) | 0x7f)
-
/*
* These 2 parameters are used to config the controls for Pause-Loop Exiting:
* ple_gap: upper bound on the amount of time between two successive
@@ -1036,6 +1033,12 @@ static inline bool pt_can_write_msr(struct vcpu_vmx *vmx)
!(vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN);
}
+static inline bool pt_output_base_valid(struct kvm_vcpu *vcpu, u64 base)
+{
+ /* The base must be 128-byte aligned and a legal physical address. */
+ return !(base & (~((1UL << cpuid_maxphyaddr(vcpu)) - 1) | 0x7f));
+}
+
static inline void pt_load_msr(struct pt_ctx *ctx, u32 addr_range)
{
u32 i;
@@ -2193,7 +2196,7 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
!intel_pt_validate_cap(vmx->pt_desc.caps,
PT_CAP_single_range_output))
return 1;
- if (data & MSR_IA32_RTIT_OUTPUT_BASE_MASK)
+ if (!pt_output_base_valid(vcpu, data))
return 1;
vmx->pt_desc.guest.output_base = data;
break;
--
2.26.0
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH 3/3] KVM: x86: Unexport cpuid_query_maxphyaddr()
2020-07-16 3:44 [PATCH 0/3] KVM: VMX: Clean up RTIT MAXPHYADDR usage Sean Christopherson
2020-07-16 3:44 ` [PATCH 1/3] KVM: VMX: Use precomputed MAXPHYADDR for RTIT base MSR check Sean Christopherson
2020-07-16 3:44 ` [PATCH 2/3] KVM: VMX: Replace MSR_IA32_RTIT_OUTPUT_BASE_MASK with helper function Sean Christopherson
@ 2020-07-16 3:44 ` Sean Christopherson
2 siblings, 0 replies; 4+ messages in thread
From: Sean Christopherson @ 2020-07-16 3:44 UTC (permalink / raw)
To: Paolo Bonzini
Cc: Sean Christopherson, Vitaly Kuznetsov, Wanpeng Li, Jim Mattson,
Joerg Roedel, kvm, linux-kernel
Stop exporting cpuid_query_maxphyaddr() now that it's not being abused
by VMX.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
arch/x86/kvm/cpuid.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 7d92854082a14..e4a8065fbddd7 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -188,7 +188,6 @@ int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu)
not_found:
return 36;
}
-EXPORT_SYMBOL_GPL(cpuid_query_maxphyaddr);
/* when an old userspace process fills a new kernel module */
int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
--
2.26.0
^ permalink raw reply related [flat|nested] 4+ messages in thread
end of thread, other threads:[~2020-07-16 3:44 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-07-16 3:44 [PATCH 0/3] KVM: VMX: Clean up RTIT MAXPHYADDR usage Sean Christopherson
2020-07-16 3:44 ` [PATCH 1/3] KVM: VMX: Use precomputed MAXPHYADDR for RTIT base MSR check Sean Christopherson
2020-07-16 3:44 ` [PATCH 2/3] KVM: VMX: Replace MSR_IA32_RTIT_OUTPUT_BASE_MASK with helper function Sean Christopherson
2020-07-16 3:44 ` [PATCH 3/3] KVM: x86: Unexport cpuid_query_maxphyaddr() Sean Christopherson
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