Merge branch 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 paravirt changes from Ingo Molnar:
 "Hypervisor signature detection cleanup and fixes - the goal is to make
  KVM guests run better on MS/Hyperv and to generalize and factor out
  the code a bit"

* 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Correctly detect hypervisor
  x86, kvm: Switch to use hypervisor_cpuid_base()
  xen: Switch to use hypervisor_cpuid_base()
  x86: Introduce hypervisor_cpuid_base()

9 files changed, 50 insertions, 58 deletions

diff --git a/arch/x86/include/asm/hypervisor.h b/arch/x86/include/asm/hypervisor.h
index 2d4b5e6107cd..e42f758a0fbd 100644
--- a/arch/x86/include/asm/hypervisor.h
+++ b/arch/x86/include/asm/hypervisor.h
@@ -33,7 +33,7 @@ struct hypervisor_x86 {
         const char      *name;
 
         /* Detection routine */
-        bool            (*detect)(void);
+        uint32_t        (*detect)(void);
 
         /* Adjust CPU feature bits (run once per CPU) */
         void            (*set_cpu_features)(struct cpuinfo_x86 *);
diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h
index 695399f2d5eb..0644129a5333 100644
--- a/arch/x86/include/asm/kvm_para.h
+++ b/arch/x86/include/asm/kvm_para.h
@@ -85,26 +85,20 @@ static inline long kvm_hypercall4(unsigned int nr, unsigned long p1,
         return ret;
 }
 
-static inline bool kvm_para_available(void)
+static inline uint32_t kvm_cpuid_base(void)
 {
-        unsigned int eax, ebx, ecx, edx;
-        char signature[13];
-
         if (boot_cpu_data.cpuid_level < 0)
-                return false;   /* So we don't blow up on old processors */
+                return 0;       /* So we don't blow up on old processors */
 
-        if (cpu_has_hypervisor) {
-                cpuid(KVM_CPUID_SIGNATURE, &eax, &ebx, &ecx, &edx);
-                memcpy(signature + 0, &ebx, 4);
-                memcpy(signature + 4, &ecx, 4);
-                memcpy(signature + 8, &edx, 4);
-                signature[12] = 0;
+        if (cpu_has_hypervisor)
+                return hypervisor_cpuid_base("KVMKVMKVM\0\0\0", 0);
 
-                if (strcmp(signature, "KVMKVMKVM") == 0)
-                        return true;
-        }
+        return 0;
+}
 
-        return false;
+static inline bool kvm_para_available(void)
+{
+        return kvm_cpuid_base() != 0;
 }
 
 static inline unsigned int kvm_arch_para_features(void)
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 4c2d31d941ea..987c75ecc334 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -942,6 +942,21 @@ extern int set_tsc_mode(unsigned int val);
 
 extern u16 amd_get_nb_id(int cpu);
 
+static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
+{
+        uint32_t base, eax, signature[3];
+
+        for (base = 0x40000000; base < 0x40010000; base += 0x100) {
+                cpuid(base, &eax, &signature[0], &signature[1], &signature[2]);
+
+                if (!memcmp(sig, signature, 12) &&
+                    (leaves == 0 || ((eax - base) >= leaves)))
+                        return base;
+        }
+
+        return 0;
+}
+
 extern unsigned long arch_align_stack(unsigned long sp);
 extern void free_init_pages(char *what, unsigned long begin, unsigned long end);
 
diff --git a/arch/x86/include/asm/xen/hypervisor.h b/arch/x86/include/asm/xen/hypervisor.h
index 125f344f06a9..d866959e5685 100644
--- a/arch/x86/include/asm/xen/hypervisor.h
+++ b/arch/x86/include/asm/xen/hypervisor.h
@@ -40,21 +40,7 @@ extern struct start_info *xen_start_info;
 
 static inline uint32_t xen_cpuid_base(void)
 {
-        uint32_t base, eax, ebx, ecx, edx;
-        char signature[13];
-
-        for (base = 0x40000000; base < 0x40010000; base += 0x100) {
-                cpuid(base, &eax, &ebx, &ecx, &edx);
-                *(uint32_t *)(signature + 0) = ebx;
-                *(uint32_t *)(signature + 4) = ecx;
-                *(uint32_t *)(signature + 8) = edx;
-                signature[12] = 0;
-
-                if (!strcmp("XenVMMXenVMM", signature) && ((eax - base) >= 2))
-                        return base;
-        }
-
-        return 0;
+        return hypervisor_cpuid_base("XenVMMXenVMM", 2);
 }
 
 #ifdef CONFIG_XEN
diff --git a/arch/x86/kernel/cpu/hypervisor.c b/arch/x86/kernel/cpu/hypervisor.c
index 87279212d318..36ce402a3fa5 100644
--- a/arch/x86/kernel/cpu/hypervisor.c
+++ b/arch/x86/kernel/cpu/hypervisor.c
@@ -25,11 +25,6 @@
 #include <asm/processor.h>
 #include <asm/hypervisor.h>
 
-/*
- * Hypervisor detect order.  This is specified explicitly here because
- * some hypervisors might implement compatibility modes for other
- * hypervisors and therefore need to be detected in specific sequence.
- */
 static const __initconst struct hypervisor_x86 * const hypervisors[] =
 {
 #ifdef CONFIG_XEN_PVHVM
@@ -49,15 +44,19 @@ static inline void __init
 detect_hypervisor_vendor(void)
 {
         const struct hypervisor_x86 *h, * const *p;
+        uint32_t pri, max_pri = 0;
 
         for (p = hypervisors; p < hypervisors + ARRAY_SIZE(hypervisors); p++) {
                 h = *p;
-                if (h->detect()) {
+                pri = h->detect();
+                if (pri != 0 && pri > max_pri) {
+                        max_pri = pri;
                         x86_hyper = h;
-                        printk(KERN_INFO "Hypervisor detected: %s\n", h->name);
-                        break;
                 }
         }
+
+        if (max_pri)
+                printk(KERN_INFO "Hypervisor detected: %s\n", x86_hyper->name);
 }
 
 void init_hypervisor(struct cpuinfo_x86 *c)
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 8f4be53ea04b..71a39f3621ba 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -27,20 +27,23 @@
 struct ms_hyperv_info ms_hyperv;
 EXPORT_SYMBOL_GPL(ms_hyperv);
 
-static bool __init ms_hyperv_platform(void)
+static uint32_t  __init ms_hyperv_platform(void)
 {
         u32 eax;
         u32 hyp_signature[3];
 
         if (!boot_cpu_has(X86_FEATURE_HYPERVISOR))
-                return false;
+                return 0;
 
         cpuid(HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS,
               &eax, &hyp_signature[0], &hyp_signature[1], &hyp_signature[2]);
 
-        return eax >= HYPERV_CPUID_MIN &&
-                eax <= HYPERV_CPUID_MAX &&
-                !memcmp("Microsoft Hv", hyp_signature, 12);
+        if (eax >= HYPERV_CPUID_MIN &&
+            eax <= HYPERV_CPUID_MAX &&
+            !memcmp("Microsoft Hv", hyp_signature, 12))
+                return HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS;
+
+        return 0;
 }
 
 static cycle_t read_hv_clock(struct clocksource *arg)
diff --git a/arch/x86/kernel/cpu/vmware.c b/arch/x86/kernel/cpu/vmware.c
index 7076878404ec..628a059a9a06 100644
--- a/arch/x86/kernel/cpu/vmware.c
+++ b/arch/x86/kernel/cpu/vmware.c
@@ -93,7 +93,7 @@ static void __init vmware_platform_setup(void)
  * serial key should be enough, as this will always have a VMware
  * specific string when running under VMware hypervisor.
  */
-static bool __init vmware_platform(void)
+static uint32_t __init vmware_platform(void)
 {
         if (cpu_has_hypervisor) {
                 unsigned int eax;
@@ -102,12 +102,12 @@ static bool __init vmware_platform(void)
                 cpuid(CPUID_VMWARE_INFO_LEAF, &eax, &hyper_vendor_id[0],
                       &hyper_vendor_id[1], &hyper_vendor_id[2]);
                 if (!memcmp(hyper_vendor_id, "VMwareVMware", 12))
-                        return true;
+                        return CPUID_VMWARE_INFO_LEAF;
         } else if (dmi_available && dmi_name_in_serial("VMware") &&
                    __vmware_platform())
-                return true;
+                return 1;
 
-        return false;
+        return 0;
 }
 
 /*
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index a96d32cc55b8..7817afdac301 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -498,11 +498,9 @@ void __init kvm_guest_init(void)
 #endif
 }
 
-static bool __init kvm_detect(void)
+static uint32_t __init kvm_detect(void)
 {
-        if (!kvm_para_available())
-                return false;
-        return true;
+        return kvm_cpuid_base();
 }
 
 const struct hypervisor_x86 x86_hyper_kvm __refconst = {
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 193097ef3d7d..2fcaedc0b739 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1720,15 +1720,12 @@ static void __init xen_hvm_guest_init(void)
         xen_hvm_init_mmu_ops();
 }
 
-static bool __init xen_hvm_platform(void)
+static uint32_t __init xen_hvm_platform(void)
 {
         if (xen_pv_domain())
-                return false;
-
-        if (!xen_cpuid_base())
-                return false;
+                return 0;
 
-        return true;
+        return xen_cpuid_base();
 }
 
 bool xen_hvm_need_lapic(void)