]> asedeno.scripts.mit.edu Git - linux.git/commitdiff
x86/vmware: Update platform detection code for VMCALL/VMMCALL hypercalls
authorThomas Hellstrom <thellstrom@vmware.com>
Wed, 28 Aug 2019 08:03:50 +0000 (10:03 +0200)
committerBorislav Petkov <bp@suse.de>
Wed, 28 Aug 2019 08:48:30 +0000 (10:48 +0200)
Vmware has historically used an INL instruction for this, but recent
hardware versions support using VMCALL/VMMCALL instead, so use this
method if supported at platform detection time. Explicitly code separate
macro versions since the alternatives self-patching has not been
performed at platform detection time.

Also put tighter constraints on the assembly input parameters.

Co-developed-by: Doug Covelli <dcovelli@vmware.com>
Signed-off-by: Doug Covelli <dcovelli@vmware.com>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Doug Covelli <dcovelli@vmware.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-graphics-maintainer@vmware.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: virtualization@lists.linux-foundation.org
Cc: <pv-drivers@vmware.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190828080353.12658-2-thomas_os@shipmail.org
arch/x86/kernel/cpu/vmware.c

index 3c648476d4fbabf09002690e8855816b428e424a..757dded223af42348df5bbeb3a6a937f80702ea3 100644 (file)
 #undef pr_fmt
 #define pr_fmt(fmt)    "vmware: " fmt
 
-#define CPUID_VMWARE_INFO_LEAF 0x40000000
+#define CPUID_VMWARE_INFO_LEAF               0x40000000
+#define CPUID_VMWARE_FEATURES_LEAF           0x40000010
+#define CPUID_VMWARE_FEATURES_ECX_VMMCALL    BIT(0)
+#define CPUID_VMWARE_FEATURES_ECX_VMCALL     BIT(1)
+
 #define VMWARE_HYPERVISOR_MAGIC        0x564D5868
 #define VMWARE_HYPERVISOR_PORT 0x5658
 
-#define VMWARE_PORT_CMD_GETVERSION     10
-#define VMWARE_PORT_CMD_GETHZ          45
-#define VMWARE_PORT_CMD_GETVCPU_INFO   68
-#define VMWARE_PORT_CMD_LEGACY_X2APIC  3
-#define VMWARE_PORT_CMD_VCPU_RESERVED  31
+#define VMWARE_CMD_GETVERSION    10
+#define VMWARE_CMD_GETHZ         45
+#define VMWARE_CMD_GETVCPU_INFO  68
+#define VMWARE_CMD_LEGACY_X2APIC  3
+#define VMWARE_CMD_VCPU_RESERVED 31
 
 #define VMWARE_PORT(cmd, eax, ebx, ecx, edx)                           \
        __asm__("inl (%%dx)" :                                          \
-                       "=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) :    \
-                       "0"(VMWARE_HYPERVISOR_MAGIC),                   \
-                       "1"(VMWARE_PORT_CMD_##cmd),                     \
-                       "2"(VMWARE_HYPERVISOR_PORT), "3"(UINT_MAX) :    \
-                       "memory");
+               "=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) :            \
+               "a"(VMWARE_HYPERVISOR_MAGIC),                           \
+               "c"(VMWARE_CMD_##cmd),                                  \
+               "d"(VMWARE_HYPERVISOR_PORT), "b"(UINT_MAX) :            \
+               "memory")
+
+#define VMWARE_VMCALL(cmd, eax, ebx, ecx, edx)                         \
+       __asm__("vmcall" :                                              \
+               "=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) :            \
+               "a"(VMWARE_HYPERVISOR_MAGIC),                           \
+               "c"(VMWARE_CMD_##cmd),                                  \
+               "d"(0), "b"(UINT_MAX) :                                 \
+               "memory")
+
+#define VMWARE_VMMCALL(cmd, eax, ebx, ecx, edx)                         \
+       __asm__("vmmcall" :                                             \
+               "=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) :            \
+               "a"(VMWARE_HYPERVISOR_MAGIC),                           \
+               "c"(VMWARE_CMD_##cmd),                                  \
+               "d"(0), "b"(UINT_MAX) :                                 \
+               "memory")
+
+#define VMWARE_CMD(cmd, eax, ebx, ecx, edx) do {               \
+       switch (vmware_hypercall_mode) {                        \
+       case CPUID_VMWARE_FEATURES_ECX_VMCALL:                  \
+               VMWARE_VMCALL(cmd, eax, ebx, ecx, edx);         \
+               break;                                          \
+       case CPUID_VMWARE_FEATURES_ECX_VMMCALL:                 \
+               VMWARE_VMMCALL(cmd, eax, ebx, ecx, edx);        \
+               break;                                          \
+       default:                                                \
+               VMWARE_PORT(cmd, eax, ebx, ecx, edx);           \
+               break;                                          \
+       }                                                       \
+       } while (0)
 
 static unsigned long vmware_tsc_khz __ro_after_init;
+static u8 vmware_hypercall_mode     __ro_after_init;
 
 static inline int __vmware_platform(void)
 {
        uint32_t eax, ebx, ecx, edx;
-       VMWARE_PORT(GETVERSION, eax, ebx, ecx, edx);
+       VMWARE_CMD(GETVERSION, eax, ebx, ecx, edx);
        return eax != (uint32_t)-1 && ebx == VMWARE_HYPERVISOR_MAGIC;
 }
 
@@ -136,7 +171,7 @@ static void __init vmware_platform_setup(void)
        uint32_t eax, ebx, ecx, edx;
        uint64_t lpj, tsc_khz;
 
-       VMWARE_PORT(GETHZ, eax, ebx, ecx, edx);
+       VMWARE_CMD(GETHZ, eax, ebx, ecx, edx);
 
        if (ebx != UINT_MAX) {
                lpj = tsc_khz = eax | (((uint64_t)ebx) << 32);
@@ -174,10 +209,21 @@ static void __init vmware_platform_setup(void)
        vmware_set_capabilities();
 }
 
+static u8 vmware_select_hypercall(void)
+{
+       int eax, ebx, ecx, edx;
+
+       cpuid(CPUID_VMWARE_FEATURES_LEAF, &eax, &ebx, &ecx, &edx);
+       return (ecx & (CPUID_VMWARE_FEATURES_ECX_VMMCALL |
+                      CPUID_VMWARE_FEATURES_ECX_VMCALL));
+}
+
 /*
  * While checking the dmi string information, just checking the product
  * serial key should be enough, as this will always have a VMware
  * specific string when running under VMware hypervisor.
+ * If !boot_cpu_has(X86_FEATURE_HYPERVISOR), vmware_hypercall_mode
+ * intentionally defaults to 0.
  */
 static uint32_t __init vmware_platform(void)
 {
@@ -187,8 +233,16 @@ static uint32_t __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))
+               if (!memcmp(hyper_vendor_id, "VMwareVMware", 12)) {
+                       if (eax >= CPUID_VMWARE_FEATURES_LEAF)
+                               vmware_hypercall_mode =
+                                       vmware_select_hypercall();
+
+                       pr_info("hypercall mode: 0x%02x\n",
+                               (unsigned int) vmware_hypercall_mode);
+
                        return CPUID_VMWARE_INFO_LEAF;
+               }
        } else if (dmi_available && dmi_name_in_serial("VMware") &&
                   __vmware_platform())
                return 1;
@@ -200,9 +254,9 @@ static uint32_t __init vmware_platform(void)
 static bool __init vmware_legacy_x2apic_available(void)
 {
        uint32_t eax, ebx, ecx, edx;
-       VMWARE_PORT(GETVCPU_INFO, eax, ebx, ecx, edx);
-       return (eax & (1 << VMWARE_PORT_CMD_VCPU_RESERVED)) == 0 &&
-              (eax & (1 << VMWARE_PORT_CMD_LEGACY_X2APIC)) != 0;
+       VMWARE_CMD(GETVCPU_INFO, eax, ebx, ecx, edx);
+       return (eax & (1 << VMWARE_CMD_VCPU_RESERVED)) == 0 &&
+              (eax & (1 << VMWARE_CMD_LEGACY_X2APIC)) != 0;
 }
 
 const __initconst struct hypervisor_x86 x86_hyper_vmware = {