From: Thomas Hellstrom Date: Wed, 28 Aug 2019 08:03:50 +0000 (+0200) Subject: x86/vmware: Update platform detection code for VMCALL/VMMCALL hypercalls X-Git-Tag: v5.4-rc1~167^2~3 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=bac7b4e843232a3a49a042410cf743341eb0887e;p=linux.git x86/vmware: Update platform detection code for VMCALL/VMMCALL hypercalls 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 Signed-off-by: Doug Covelli Signed-off-by: Thomas Hellstrom Signed-off-by: Borislav Petkov Reviewed-by: Doug Covelli Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: linux-graphics-maintainer@vmware.com Cc: Thomas Gleixner Cc: virtualization@lists.linux-foundation.org Cc: Cc: x86-ml Link: https://lkml.kernel.org/r/20190828080353.12658-2-thomas_os@shipmail.org --- diff --git a/arch/x86/kernel/cpu/vmware.c b/arch/x86/kernel/cpu/vmware.c index 3c648476d4fb..757dded223af 100644 --- a/arch/x86/kernel/cpu/vmware.c +++ b/arch/x86/kernel/cpu/vmware.c @@ -34,30 +34,65 @@ #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 = {