From 29282fde80d44e587f8c152b10049a56e61659f0 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Fri, 9 Nov 2012 15:20:17 +0100 Subject: [PATCH] KVM: x86: Fix invalid secondary exec controls in vmx_cpuid_update() The commit [ad756a16: KVM: VMX: Implement PCID/INVPCID for guests with EPT] introduced the unconditional access to SECONDARY_VM_EXEC_CONTROL, and this triggers kernel warnings like below on old CPUs: vmwrite error: reg 401e value a0568000 (err 12) Pid: 13649, comm: qemu-kvm Not tainted 3.7.0-rc4-test2+ #154 Call Trace: [] vmwrite_error+0x27/0x29 [kvm_intel] [] vmcs_writel+0x1b/0x20 [kvm_intel] [] vmx_cpuid_update+0x74/0x170 [kvm_intel] [] kvm_vcpu_ioctl_set_cpuid2+0x76/0x90 [kvm] [] kvm_arch_vcpu_ioctl+0xc37/0xed0 [kvm] [] ? __vunmap+0x9c/0x110 [] ? vmx_vcpu_load+0x39/0x1a0 [kvm_intel] [] ? kvm_arch_vcpu_load+0x52/0x1a0 [kvm] [] ? vcpu_load+0x74/0xd0 [kvm] [] kvm_vcpu_ioctl+0x110/0x5e0 [kvm] [] ? kvm_dev_ioctl+0x4d/0x4a0 [kvm] [] do_vfs_ioctl+0x8f/0x530 [] ? remove_vma+0x56/0x60 [] ? do_munmap+0x328/0x400 [] ? fget_light+0x4c/0x100 [] sys_ioctl+0x91/0xb0 [] system_call_fastpath+0x1a/0x1f This patch adds a check for the availability of secondary exec control to avoid these warnings. Cc: [v3.6+] Signed-off-by: Takashi Iwai Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/vmx.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index ad6b1dd06f8b..f85815945fc6 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -6549,19 +6549,22 @@ static void vmx_cpuid_update(struct kvm_vcpu *vcpu) } } - exec_control = vmcs_read32(SECONDARY_VM_EXEC_CONTROL); /* Exposing INVPCID only when PCID is exposed */ best = kvm_find_cpuid_entry(vcpu, 0x7, 0); if (vmx_invpcid_supported() && best && (best->ebx & bit(X86_FEATURE_INVPCID)) && guest_cpuid_has_pcid(vcpu)) { + exec_control = vmcs_read32(SECONDARY_VM_EXEC_CONTROL); exec_control |= SECONDARY_EXEC_ENABLE_INVPCID; vmcs_write32(SECONDARY_VM_EXEC_CONTROL, exec_control); } else { - exec_control &= ~SECONDARY_EXEC_ENABLE_INVPCID; - vmcs_write32(SECONDARY_VM_EXEC_CONTROL, - exec_control); + if (cpu_has_secondary_exec_ctrls()) { + exec_control = vmcs_read32(SECONDARY_VM_EXEC_CONTROL); + exec_control &= ~SECONDARY_EXEC_ENABLE_INVPCID; + vmcs_write32(SECONDARY_VM_EXEC_CONTROL, + exec_control); + } if (best) best->ebx &= ~bit(X86_FEATURE_INVPCID); }