From: Sean Christopherson <seanjc@google.com>
To: Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>,
x86@kernel.org, Sean Christopherson <seanjc@google.com>,
Paolo Bonzini <pbonzini@redhat.com>
Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
Andrew Cooper <Andrew.Cooper3@citrix.com>,
Kai Huang <kai.huang@intel.com>, Chao Gao <chao.gao@intel.com>
Subject: [PATCH v2 18/18] KVM: SVM: Use "standard" stgi() helper when disabling SVM
Date: Fri, 10 Mar 2023 13:42:32 -0800 [thread overview]
Message-ID: <20230310214232.806108-19-seanjc@google.com> (raw)
In-Reply-To: <20230310214232.806108-1-seanjc@google.com>
Now that kvm_rebooting is guaranteed to be true prior to disabling SVM
in an emergency, use the existing stgi() helper instead of open coding
STGI. In effect, eat faults on STGI if and only if kvm_rebooting==true.
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/x86/kvm/svm/svm.c | 13 +++----------
1 file changed, 3 insertions(+), 10 deletions(-)
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 30f7840151be..420b35770f0a 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -591,17 +591,10 @@ static inline void kvm_cpu_svm_disable(void)
rdmsrl(MSR_EFER, efer);
if (efer & EFER_SVME) {
/*
- * Force GIF=1 prior to disabling SVM to ensure INIT and NMI
- * aren't blocked, e.g. if a fatal error occurred between CLGI
- * and STGI. Note, STGI may #UD if SVM is disabled from NMI
- * context between reading EFER and executing STGI. In that
- * case, GIF must already be set, otherwise the NMI would have
- * been blocked, so just eat the fault.
+ * Force GIF=1 prior to disabling SVM, e.g. to ensure INIT and
+ * NMI aren't blocked.
*/
- asm_volatile_goto("1: stgi\n\t"
- _ASM_EXTABLE(1b, %l[fault])
- ::: "memory" : fault);
-fault:
+ stgi();
wrmsrl(MSR_EFER, efer & ~EFER_SVME);
}
}
--
2.40.0.rc1.284.g88254d51c5-goog
prev parent reply other threads:[~2023-03-10 21:45 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-03-10 21:42 [PATCH v2 00/18] x86/reboot: KVM: Clean up "emergency" virt code Sean Christopherson
2023-03-10 21:42 ` [PATCH v2 01/18] x86/reboot: VMCLEAR active VMCSes before emergency reboot Sean Christopherson
2023-03-10 21:42 ` [PATCH v2 02/18] x86/reboot: Expose VMCS crash hooks if and only if KVM_INTEL is enabled Sean Christopherson
2023-03-13 0:31 ` Huang, Kai
2023-03-13 18:31 ` Sean Christopherson
2023-03-14 1:19 ` Huang, Kai
2023-03-10 21:42 ` [PATCH v2 03/18] x86/reboot: Harden virtualization hooks for emergency reboot Sean Christopherson
2023-03-13 8:26 ` Chao Gao
2023-03-13 17:08 ` Sean Christopherson
2023-03-10 21:42 ` [PATCH v2 04/18] x86/reboot: KVM: Handle VMXOFF in KVM's reboot callback Sean Christopherson
2023-03-10 21:42 ` [PATCH v2 05/18] x86/reboot: KVM: Disable SVM during reboot via virt/KVM " Sean Christopherson
2023-03-13 0:52 ` Huang, Kai
2023-03-13 17:18 ` Sean Christopherson
2023-03-14 0:42 ` Huang, Kai
2023-03-15 0:47 ` Sean Christopherson
2023-03-15 1:30 ` Huang, Kai
2023-03-10 21:42 ` [PATCH v2 06/18] x86/reboot: Hoist "disable virt" helpers above "emergency reboot" path Sean Christopherson
2023-03-10 21:42 ` [PATCH v2 07/18] x86/reboot: Disable virtualization during reboot iff callback is registered Sean Christopherson
2023-03-13 0:54 ` Huang, Kai
2023-03-13 18:40 ` Sean Christopherson
2023-03-14 0:50 ` Huang, Kai
2023-03-10 21:42 ` [PATCH v2 08/18] x86/reboot: Assert that IRQs are disabled when turning off virtualization Sean Christopherson
2023-03-10 21:42 ` [PATCH v2 09/18] x86/virt: KVM: Open code cpu_has_vmx() in KVM VMX Sean Christopherson
2023-03-10 21:42 ` [PATCH v2 10/18] x86/virt: KVM: Move VMXOFF helpers into " Sean Christopherson
2023-03-10 21:42 ` [PATCH v2 11/18] KVM: SVM: Make KVM_AMD depend on CPU_SUP_AMD or CPU_SUP_HYGON Sean Christopherson
2023-03-10 21:42 ` [PATCH v2 12/18] x86/virt: Drop unnecessary check on extended CPUID level in cpu_has_svm() Sean Christopherson
2023-03-10 21:42 ` [PATCH v2 13/18] x86/virt: KVM: Open code cpu_has_svm() into kvm_is_svm_supported() Sean Christopherson
2023-03-10 21:42 ` [PATCH v2 14/18] KVM: SVM: Check that the current CPU supports SVM in kvm_is_svm_supported() Sean Christopherson
2023-03-13 2:47 ` Huang, Kai
2023-03-13 17:29 ` Sean Christopherson
2023-03-14 0:17 ` Huang, Kai
2023-03-10 21:42 ` [PATCH v2 15/18] KVM: VMX: Ensure CPU is stable when probing basic VMX support Sean Christopherson
2023-03-10 21:42 ` [PATCH v2 16/18] x86/virt: KVM: Move "disable SVM" helper into KVM SVM Sean Christopherson
2023-03-10 21:42 ` [PATCH v2 17/18] KVM: x86: Force kvm_rebooting=true during emergency reboot/crash Sean Christopherson
2023-03-10 21:42 ` Sean Christopherson [this message]
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