From 22e420e127399f2e75c8efddff763e92247f3da7 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Fri, 21 Jul 2023 13:18:50 -0700 Subject: [PATCH] x86/virt: KVM: Move VMXOFF helpers into KVM VMX Now that VMX is disabled in emergencies via the virt callbacks, move the VMXOFF helpers into KVM, the only remaining user. No functional change intended. Reviewed-by: Kai Huang Link: https://lore.kernel.org/r/20230721201859.2307736-11-seanjc@google.com Signed-off-by: Sean Christopherson --- arch/x86/include/asm/virtext.h | 42 ---------------------------------- arch/x86/kvm/vmx/vmx.c | 29 ++++++++++++++++++++--- 2 files changed, 26 insertions(+), 45 deletions(-) diff --git a/arch/x86/include/asm/virtext.h b/arch/x86/include/asm/virtext.h index b1171a5ad4525..a27801f2bc71c 100644 --- a/arch/x86/include/asm/virtext.h +++ b/arch/x86/include/asm/virtext.h @@ -19,48 +19,6 @@ #include #include -/* - * VMX functions: - */ -/** - * cpu_vmxoff() - Disable VMX on the current CPU - * - * Disable VMX and clear CR4.VMXE (even if VMXOFF faults) - * - * Note, VMXOFF causes a #UD if the CPU is !post-VMXON, but it's impossible to - * atomically track post-VMXON state, e.g. this may be called in NMI context. - * Eat all faults as all other faults on VMXOFF faults are mode related, i.e. - * faults are guaranteed to be due to the !post-VMXON check unless the CPU is - * magically in RM, VM86, compat mode, or at CPL>0. - */ -static inline int cpu_vmxoff(void) -{ - asm_volatile_goto("1: vmxoff\n\t" - _ASM_EXTABLE(1b, %l[fault]) - ::: "cc", "memory" : fault); - - cr4_clear_bits(X86_CR4_VMXE); - return 0; - -fault: - cr4_clear_bits(X86_CR4_VMXE); - return -EIO; -} - -static inline int cpu_vmx_enabled(void) -{ - return __read_cr4() & X86_CR4_VMXE; -} - -/** Disable VMX if it is enabled on the current CPU - */ -static inline void __cpu_emergency_vmxoff(void) -{ - if (cpu_vmx_enabled()) - cpu_vmxoff(); -} - - /* * SVM functions: */ diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 4b9d688261726..64377fe3a9904 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -47,7 +47,6 @@ #include #include #include -#include #include #include "capabilities.h" @@ -725,6 +724,29 @@ static int vmx_set_guest_uret_msr(struct vcpu_vmx *vmx, return ret; } +/* + * Disable VMX and clear CR4.VMXE (even if VMXOFF faults) + * + * Note, VMXOFF causes a #UD if the CPU is !post-VMXON, but it's impossible to + * atomically track post-VMXON state, e.g. this may be called in NMI context. + * Eat all faults as all other faults on VMXOFF faults are mode related, i.e. + * faults are guaranteed to be due to the !post-VMXON check unless the CPU is + * magically in RM, VM86, compat mode, or at CPL>0. + */ +static int kvm_cpu_vmxoff(void) +{ + asm_volatile_goto("1: vmxoff\n\t" + _ASM_EXTABLE(1b, %l[fault]) + ::: "cc", "memory" : fault); + + cr4_clear_bits(X86_CR4_VMXE); + return 0; + +fault: + cr4_clear_bits(X86_CR4_VMXE); + return -EIO; +} + static void vmx_emergency_disable(void) { int cpu = raw_smp_processor_id(); @@ -734,7 +756,8 @@ static void vmx_emergency_disable(void) loaded_vmcss_on_cpu_link) vmcs_clear(v->vmcs); - __cpu_emergency_vmxoff(); + if (__read_cr4() & X86_CR4_VMXE) + kvm_cpu_vmxoff(); } static void __loaded_vmcs_clear(void *arg) @@ -2799,7 +2822,7 @@ static void vmx_hardware_disable(void) { vmclear_local_loaded_vmcss(); - if (cpu_vmxoff()) + if (kvm_cpu_vmxoff()) kvm_spurious_fault(); hv_reset_evmcs(); -- 2.30.2