From: Sean Christopherson <sean.j.christopherson@intel.com>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>,
Vitaly Kuznetsov <vkuznets@redhat.com>,
Wanpeng Li <wanpengli@tencent.com>,
Jim Mattson <jmattson@google.com>, Joerg Roedel <joro@8bytes.org>,
kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH 24/26] KVM: x86: Clear output regs for CPUID 0x14 if PT isn't exposed to guest
Date: Wed, 29 Jan 2020 15:46:38 -0800 [thread overview]
Message-ID: <20200129234640.8147-25-sean.j.christopherson@intel.com> (raw)
In-Reply-To: <20200129234640.8147-1-sean.j.christopherson@intel.com>
Clear the output regs for the main CPUID 0x14 leaf (index=0) if Intel PT
isn't exposed to the guest. Leaf 0x14 enumerates Intel PT capabilities
and should return zeroes if PT is not supported. Incorrectly reporting
PT capabilities is essentially a cosmetic error, i.e. doesn't negatively
affect any known kernel, as the existence of PT itself is correctly
enumerated via CPUID 0x7.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
---
arch/x86/kvm/cpuid.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index eb61a1d83598..d06fb54c9c0d 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -651,8 +651,10 @@ static inline int __do_cpuid_func(struct kvm_cpuid_entry2 *entry, u32 function,
case 0x14: {
int t, times = entry->eax;
- if (!f_intel_pt)
+ if (!f_intel_pt) {
+ entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
break;
+ }
for (t = 1; t <= times; ++t) {
if (*nent >= maxnent)
--
2.24.1
next prev parent reply other threads:[~2020-01-29 23:47 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-29 23:46 [PATCH 00/26] KVM: x86: Purge kvm_x86_ops->*_supported() Sean Christopherson
2020-01-29 23:46 ` [PATCH 01/26] KVM: x86: Remove superfluous brackets from case statement Sean Christopherson
2020-02-05 14:29 ` Vitaly Kuznetsov
2020-02-05 14:32 ` Sean Christopherson
2020-01-29 23:46 ` [PATCH 02/26] KVM: x86: Take an unsigned 32-bit int for has_emulated_msr()'s index Sean Christopherson
2020-02-05 14:30 ` Vitaly Kuznetsov
2020-01-29 23:46 ` [PATCH 03/26] KVM: x86: Snapshot MSR index in a local variable when processing lists Sean Christopherson
2020-02-05 14:31 ` Vitaly Kuznetsov
2020-01-29 23:46 ` [PATCH 04/26] KVM: x86: Add a kvm_x86_ops hook to query virtualized MSR support Sean Christopherson
2020-02-05 14:34 ` Vitaly Kuznetsov
2020-02-05 14:59 ` Sean Christopherson
2020-02-05 15:22 ` Vitaly Kuznetsov
2020-02-05 15:35 ` Sean Christopherson
2020-02-05 16:55 ` Vitaly Kuznetsov
2020-02-05 17:02 ` Sean Christopherson
2020-02-06 12:08 ` Vitaly Kuznetsov
2020-01-29 23:46 ` [PATCH 05/26] KVM: x86: Move MSR_TSC_AUX existence checks into vendor code Sean Christopherson
2020-02-05 14:39 ` Vitaly Kuznetsov
2020-01-29 23:46 ` [PATCH 06/26] KVM: x86: Move MSR_IA32_BNDCFGS " Sean Christopherson
2020-02-05 14:53 ` Vitaly Kuznetsov
2020-01-29 23:46 ` [PATCH 07/26] KVM: VMX: Add helpers to query Intel PT mode Sean Christopherson
2020-01-29 23:46 ` [PATCH 08/26] KVM: x86: Move RTIT (Intel PT) MSR existence checks into vendor code Sean Christopherson
2020-01-29 23:46 ` [PATCH 09/26] KVM: x86: Calculate the supported xcr0 mask at load time Sean Christopherson
2020-01-29 23:46 ` [PATCH 10/26] KVM: x86: Use supported_xcr0 to detect MPX support Sean Christopherson
2020-01-29 23:46 ` [PATCH 11/26] KVM: x86: Make kvm_mpx_supported() an inline function Sean Christopherson
2020-01-29 23:46 ` [PATCH 12/26] KVM: x86: Drop explicit @func param from ->set_supported_cpuid() Sean Christopherson
2020-01-29 23:46 ` [PATCH 13/26] KVM: x86: Use u32 for holding CPUID register value in helpers Sean Christopherson
2020-01-29 23:46 ` [PATCH 14/26] KVM: x86: Introduce cpuid_entry_{get,has}() accessors Sean Christopherson
2020-01-29 23:46 ` [PATCH 15/26] KVM: x86: Introduce cpuid_entry_{change,set,clear}() mutators Sean Christopherson
2020-01-29 23:46 ` [PATCH 16/26] KVM: x86: Add Kconfig-controlled auditing of reverse CPUID lookups Sean Christopherson
2020-01-29 23:46 ` [PATCH 17/26] KVM: x86: Handle MPX CPUID adjustment in vendor code Sean Christopherson
2020-01-29 23:46 ` [PATCH 18/26] KVM: x86: Handle INVPCID " Sean Christopherson
2020-01-29 23:46 ` [PATCH 19/26] KVM: x86: Handle UMIP emulation CPUID adjustment in VMX code Sean Christopherson
2020-01-29 23:46 ` [PATCH 20/26] KVM: x86: Handle PKU CPUID adjustment in SVM code Sean Christopherson
2020-01-29 23:46 ` [PATCH 21/26] KVM: x86: Handle RDTSCP CPUID adjustment in VMX code Sean Christopherson
2020-01-29 23:46 ` [PATCH 22/26] KVM: x86: Handle XSAVES " Sean Christopherson
2020-01-29 23:46 ` [PATCH 23/26] KVM: x86: Handle Intel PT CPUID adjustment in vendor code Sean Christopherson
2020-01-29 23:46 ` Sean Christopherson [this message]
2020-01-29 23:46 ` [PATCH 25/26] KVM: x86: Handle main Intel PT CPUID leaf " Sean Christopherson
2020-01-30 0:38 ` Sean Christopherson
2020-01-29 23:46 ` [PATCH 26/26] KVM: VMX: Directly query Intel PT mode when refreshing PMUs Sean Christopherson
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