linux-kernel - [PATCH v4 17/19] KVM: x86: Force kvm_rebooting=true during emergency reboot/crash

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20230721201859.2307736-18-seanjc@google.com>
Date:   Fri, 21 Jul 2023 13:18:57 -0700
From:   Sean Christopherson <seanjc@...gle.com>
To:     Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        Dave Hansen <dave.hansen@...ux.intel.com>, x86@...nel.org,
        Sean Christopherson <seanjc@...gle.com>,
        Paolo Bonzini <pbonzini@...hat.com>
Cc:     linux-kernel@...r.kernel.org, kvm@...r.kernel.org,
        Andrew Cooper <Andrew.Cooper3@...rix.com>,
        Kai Huang <kai.huang@...el.com>, Chao Gao <chao.gao@...el.com>
Subject: [PATCH v4 17/19] KVM: x86: Force kvm_rebooting=true during emergency reboot/crash

Set kvm_rebooting when virtualization is disabled in an emergency so that
KVM eats faults on virtualization instructions even if kvm_reboot() isn't
reached.

Reviewed-by: Kai Huang <kai.huang@...el.com>
Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/svm/svm.c | 2 ++
 arch/x86/kvm/vmx/vmx.c | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 47f9c7156609..8d1b3c801629 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -605,6 +605,8 @@ static inline void kvm_cpu_svm_disable(void)
 
 static void svm_emergency_disable(void)
 {
+	kvm_rebooting = true;
+
 	kvm_cpu_svm_disable();
 }
 
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 0e1f3856a9be..5d21931842a5 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -771,6 +771,8 @@ static void vmx_emergency_disable(void)
 	int cpu = raw_smp_processor_id();
 	struct loaded_vmcs *v;
 
+	kvm_rebooting = true;
+
 	list_for_each_entry(v, &per_cpu(loaded_vmcss_on_cpu, cpu),
 			    loaded_vmcss_on_cpu_link)
 		vmcs_clear(v->vmcs);
-- 
2.41.0.487.g6d72f3e995-goog