KVM: VMX: eVMCS: make evmcs_sanitize_exec_ctrls() work again

BugLink: https://bugs.launchpad.net/bugs/1950462
It was noticed that evmcs_sanitize_exec_ctrls() is not being executed
nowadays despite the code checking 'enable_evmcs' static key looking
correct. Turns out, static key magic doesn't work in '__init' section
(and it is unclear when things changed) but setup_vmcs_config() is called
only once per CPU so we don't really need it to. Switch to checking
'enlightened_vmcs' instead, it is supposed to be in sync with
'enable_evmcs'.

Opportunistically make evmcs_sanitize_exec_ctrls '__init' and drop unneeded
extra newline from it.

Reported-by: Yang Weijiang <weijiang.yang@intel.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20201014143346.2430936-1-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit 064eedf2c50f692088e1418c553084bf9c1432f8)
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

diff --git a/arch/x86/kvm/vmx/evmcs.c b/arch/x86/kvm/vmx/evmcs.c
index 72359709cdc1741beff8656b20f0432895388717..68803da7463956f6224f75c7611b046a849bafdd 100644 (file)
--- a/arch/x86/kvm/vmx/evmcs.c
+++ b/arch/x86/kvm/vmx/evmcs.c
@@ -303,14 +303,13 @@ const struct evmcs_field vmcs_field_to_evmcs_1[] = {
 };
 const unsigned int nr_evmcs_1_fields = ARRAY_SIZE(vmcs_field_to_evmcs_1);
 
-void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf)
+__init void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf)
 {
        vmcs_conf->pin_based_exec_ctrl &= ~EVMCS1_UNSUPPORTED_PINCTRL;
        vmcs_conf->cpu_based_2nd_exec_ctrl &= ~EVMCS1_UNSUPPORTED_2NDEXEC;
 
        vmcs_conf->vmexit_ctrl &= ~EVMCS1_UNSUPPORTED_VMEXIT_CTRL;
        vmcs_conf->vmentry_ctrl &= ~EVMCS1_UNSUPPORTED_VMENTRY_CTRL;
-
 }
 #endif
 

diff --git a/arch/x86/kvm/vmx/evmcs.h b/arch/x86/kvm/vmx/evmcs.h
index 07ebf6882a458ab7f85c03d0dd22aa759e6085eb..37f469f4d3b2c9f41d559928a2c7e0a8eda4eaa7 100644 (file)
--- a/arch/x86/kvm/vmx/evmcs.h
+++ b/arch/x86/kvm/vmx/evmcs.h
@@ -184,7 +184,7 @@ static inline void evmcs_load(u64 phys_addr)
        vp_ap->enlighten_vmentry = 1;
 }
 
-void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf);
+__init void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf);
 #else /* !IS_ENABLED(CONFIG_HYPERV) */
 static inline void evmcs_write64(unsigned long field, u64 value) {}
 static inline void evmcs_write32(unsigned long field, u32 value) {}
@@ -193,7 +193,6 @@ static inline u64 evmcs_read64(unsigned long field) { return 0; }
 static inline u32 evmcs_read32(unsigned long field) { return 0; }
 static inline u16 evmcs_read16(unsigned long field) { return 0; }
 static inline void evmcs_load(u64 phys_addr) {}
-static inline void evmcs_sanitize_exec_ctrls(struct vmcs_config *vmcs_conf) {}
 static inline void evmcs_touch_msr_bitmap(void) {}
 #endif /* IS_ENABLED(CONFIG_HYPERV) */
 

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index e177848a36313871b6ea12fe08c5ec1eeaa5fbaf..f5b7aae369e13288fed665082ff57da8fcb71e85 100644 (file)
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2505,8 +2505,10 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
        vmcs_conf->vmexit_ctrl         = _vmexit_control;
        vmcs_conf->vmentry_ctrl        = _vmentry_control;
 
-       if (static_branch_unlikely(&enable_evmcs))
+#if IS_ENABLED(CONFIG_HYPERV)
+       if (enlightened_vmcs)
                evmcs_sanitize_exec_ctrls(vmcs_conf);
+#endif
 
        return 0;
 }