diff --git a/host/include/i386/host/cpuinfo.h b/host/include/i386/host/cpuinfo.h index 81771733ea..9541a64da6 100644 --- a/host/include/i386/host/cpuinfo.h +++ b/host/include/i386/host/cpuinfo.h @@ -9,6 +9,7 @@ /* Digested version of */ #define CPUINFO_ALWAYS (1u << 0) /* so cpuinfo is nonzero */ +#define CPUINFO_OSXSAVE (1u << 1) #define CPUINFO_MOVBE (1u << 2) #define CPUINFO_LZCNT (1u << 3) #define CPUINFO_POPCNT (1u << 4) diff --git a/target/i386/hvf/x86_cpuid.c b/target/i386/hvf/x86_cpuid.c index e56cd8411b..3a116548a3 100644 --- a/target/i386/hvf/x86_cpuid.c +++ b/target/i386/hvf/x86_cpuid.c @@ -21,28 +21,38 @@ */ #include "qemu/osdep.h" +#include "qemu/cpuid.h" +#include "host/cpuinfo.h" #include "cpu.h" #include "x86.h" #include "vmx.h" #include "sysemu/hvf.h" #include "hvf-i386.h" -static bool xgetbv(uint32_t cpuid_ecx, uint32_t idx, uint64_t *xcr) +static bool cached_xcr0; +static uint64_t supported_xcr0; + +static void cache_host_xcr0() { - uint32_t xcrl, xcrh; - - if (cpuid_ecx & CPUID_EXT_OSXSAVE) { - /* - * The xgetbv instruction is not available to older versions of - * the assembler, so we encode the instruction manually. - */ - asm(".byte 0x0f, 0x01, 0xd0" : "=a" (xcrl), "=d" (xcrh) : "c" (idx)); - - *xcr = (((uint64_t)xcrh) << 32) | xcrl; - return true; + if (cached_xcr0) { + return; } - return false; + if (cpuinfo & CPUINFO_OSXSAVE) { + uint64_t host_xcr0 = xgetbv_low(0); + + /* Only show xcr0 bits corresponding to usable features. */ + supported_xcr0 = host_xcr0 & (XSTATE_FP_MASK | + XSTATE_SSE_MASK | XSTATE_YMM_MASK | + XSTATE_OPMASK_MASK | XSTATE_ZMM_Hi256_MASK | + XSTATE_Hi16_ZMM_MASK); + if ((supported_xcr0 & (XSTATE_FP_MASK | XSTATE_SSE_MASK)) != + (XSTATE_FP_MASK | XSTATE_SSE_MASK)) { + supported_xcr0 = 0; + } + } + + cached_xcr0 = true; } uint32_t hvf_get_supported_cpuid(uint32_t func, uint32_t idx, @@ -51,6 +61,7 @@ uint32_t hvf_get_supported_cpuid(uint32_t func, uint32_t idx, uint64_t cap; uint32_t eax, ebx, ecx, edx; + cache_host_xcr0(); host_cpuid(func, idx, &eax, &ebx, &ecx, &edx); switch (func) { @@ -66,7 +77,8 @@ uint32_t hvf_get_supported_cpuid(uint32_t func, uint32_t idx, ecx &= CPUID_EXT_SSE3 | CPUID_EXT_PCLMULQDQ | CPUID_EXT_SSSE3 | CPUID_EXT_FMA | CPUID_EXT_CX16 | CPUID_EXT_PCID | CPUID_EXT_SSE41 | CPUID_EXT_SSE42 | CPUID_EXT_MOVBE | - CPUID_EXT_POPCNT | CPUID_EXT_AES | CPUID_EXT_XSAVE | + CPUID_EXT_POPCNT | CPUID_EXT_AES | + (supported_xcr0 ? CPUID_EXT_XSAVE : 0) | CPUID_EXT_AVX | CPUID_EXT_F16C | CPUID_EXT_RDRAND; ecx |= CPUID_EXT_HYPERVISOR; break; @@ -107,16 +119,14 @@ uint32_t hvf_get_supported_cpuid(uint32_t func, uint32_t idx, eax = 0; break; case 0xD: + if (!supported_xcr0 || + (idx > 1 && !(supported_xcr0 & (1 << idx)))) { + eax = ebx = ecx = edx = 0; + break; + } + if (idx == 0) { - uint64_t host_xcr0; - if (xgetbv(ecx, 0, &host_xcr0)) { - uint64_t supp_xcr0 = host_xcr0 & (XSTATE_FP_MASK | - XSTATE_SSE_MASK | XSTATE_YMM_MASK | - XSTATE_BNDREGS_MASK | XSTATE_BNDCSR_MASK | - XSTATE_OPMASK_MASK | XSTATE_ZMM_Hi256_MASK | - XSTATE_Hi16_ZMM_MASK); - eax &= supp_xcr0; - } + eax = supported_xcr0; } else if (idx == 1) { hv_vmx_read_capability(HV_VMX_CAP_PROCBASED2, &cap); eax &= CPUID_XSAVE_XSAVEOPT | CPUID_XSAVE_XGETBV1; diff --git a/util/cpuinfo-i386.c b/util/cpuinfo-i386.c index 90f92a42dc..c8c8a1b370 100644 --- a/util/cpuinfo-i386.c +++ b/util/cpuinfo-i386.c @@ -35,6 +35,7 @@ unsigned __attribute__((constructor)) cpuinfo_init(void) __cpuid(1, a, b, c, d); info |= (d & bit_SSE2 ? CPUINFO_SSE2 : 0); + info |= (c & bit_OSXSAVE ? CPUINFO_OSXSAVE : 0); info |= (c & bit_MOVBE ? CPUINFO_MOVBE : 0); info |= (c & bit_POPCNT ? CPUINFO_POPCNT : 0); info |= (c & bit_PCLMUL ? CPUINFO_PCLMUL : 0);