KVM: VMX: fixes for vmentry_l1d_flush module parameter

[mirror_ubuntu-bionic-kernel.git] / arch / x86 / kvm / vmx.c

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 37b095e7f00a38e406be7336798d3947b8449bc5..1b135b6232ccc8372ccdd2e0b1ce273e2a09b39f 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -203,12 +203,14 @@ static enum vmx_l1d_flush_state __read_mostly vmentry_l1d_flush_param = VMENTER_
 
 static const struct {
        const char *option;
-       enum vmx_l1d_flush_state cmd;
+       bool for_parse;
 } vmentry_l1d_param[] = {
-       {"auto",        VMENTER_L1D_FLUSH_AUTO},
-       {"never",       VMENTER_L1D_FLUSH_NEVER},
-       {"cond",        VMENTER_L1D_FLUSH_COND},
-       {"always",      VMENTER_L1D_FLUSH_ALWAYS},
+       [VMENTER_L1D_FLUSH_AUTO]         = {"auto", true},
+       [VMENTER_L1D_FLUSH_NEVER]        = {"never", true},
+       [VMENTER_L1D_FLUSH_COND]         = {"cond", true},
+       [VMENTER_L1D_FLUSH_ALWAYS]       = {"always", true},
+       [VMENTER_L1D_FLUSH_EPT_DISABLED] = {"EPT disabled", false},
+       [VMENTER_L1D_FLUSH_NOT_REQUIRED] = {"not required", false},
 };
 
 #define L1D_CACHE_ORDER 4
@@ -292,8 +294,9 @@ static int vmentry_l1d_flush_parse(const char *s)
 
        if (s) {
                for (i = 0; i < ARRAY_SIZE(vmentry_l1d_param); i++) {
-                       if (sysfs_streq(s, vmentry_l1d_param[i].option))
-                               return vmentry_l1d_param[i].cmd;
+                       if (vmentry_l1d_param[i].for_parse &&
+                           sysfs_streq(s, vmentry_l1d_param[i].option))
+                               return i;
                }
        }
        return -EINVAL;
@@ -303,13 +306,13 @@ static int vmentry_l1d_flush_set(const char *s, const struct kernel_param *kp)
 {
        int l1tf, ret;
 
-       if (!boot_cpu_has(X86_BUG_L1TF))
-               return 0;
-
        l1tf = vmentry_l1d_flush_parse(s);
        if (l1tf < 0)
                return l1tf;
 
+       if (!boot_cpu_has(X86_BUG_L1TF))
+               return 0;
+
        /*
         * Has vmx_init() run already? If not then this is the pre init
         * parameter parsing. In that case just store the value and let
@@ -329,6 +332,9 @@ static int vmentry_l1d_flush_set(const char *s, const struct kernel_param *kp)
 
 static int vmentry_l1d_flush_get(char *s, const struct kernel_param *kp)
 {
+       if (WARN_ON_ONCE(l1tf_vmx_mitigation >= ARRAY_SIZE(vmentry_l1d_param)))
+               return sprintf(s, "???\n");
+
        return sprintf(s, "%s\n", vmentry_l1d_param[l1tf_vmx_mitigation].option);
 }