diff options
Diffstat (limited to 'sys/amd64/vmm/x86.c')
| -rw-r--r-- | sys/amd64/vmm/x86.c | 102 |
1 files changed, 96 insertions, 6 deletions
diff --git a/sys/amd64/vmm/x86.c b/sys/amd64/vmm/x86.c index c1fc006e..455d865 100644 --- a/sys/amd64/vmm/x86.c +++ b/sys/amd64/vmm/x86.c @@ -30,17 +30,19 @@ __FBSDID("$FreeBSD$"); #include <sys/param.h> -#include <sys/types.h> +#include <sys/pcpu.h> #include <sys/systm.h> #include <sys/cpuset.h> #include <machine/clock.h> #include <machine/cpufunc.h> #include <machine/md_var.h> +#include <machine/segments.h> #include <machine/specialreg.h> #include <machine/vmm.h> +#include "vmm_host.h" #include "x86.h" #define CPUID_VM_HIGH 0x40000000 @@ -53,6 +55,8 @@ int x86_emulate_cpuid(struct vm *vm, int vcpu_id, uint32_t *eax, uint32_t *ebx, uint32_t *ecx, uint32_t *edx) { + const struct xsave_limits *limits; + uint64_t cr4; int error, enable_invpcid; unsigned int func, regs[4]; enum x2apic_state x2apic_state; @@ -147,11 +151,27 @@ x86_emulate_cpuid(struct vm *vm, int vcpu_id, regs[2] |= CPUID2_X2APIC; /* - * Hide xsave/osxsave/avx until the FPU save/restore - * issues are resolved + * Only advertise CPUID2_XSAVE in the guest if + * the host is using XSAVE. */ - regs[2] &= ~(CPUID2_XSAVE | CPUID2_OSXSAVE | - CPUID2_AVX); + if (!(regs[2] & CPUID2_OSXSAVE)) + regs[2] &= ~CPUID2_XSAVE; + + /* + * If CPUID2_XSAVE is being advertised and the + * guest has set CR4_XSAVE, set + * CPUID2_OSXSAVE. + */ + regs[2] &= ~CPUID2_OSXSAVE; + if (regs[2] & CPUID2_XSAVE) { + error = vm_get_register(vm, vcpu_id, + VM_REG_GUEST_CR4, &cr4); + if (error) + panic("x86_emulate_cpuid: error %d " + "fetching %%cr4", error); + if (cr4 & CR4_XSAVE) + regs[2] |= CPUID2_OSXSAVE; + } /* * Hide monitor/mwait until we know how to deal with @@ -210,6 +230,26 @@ x86_emulate_cpuid(struct vm *vm, int vcpu_id, /* leaf 0 */ if (*ecx == 0) { + cpuid_count(*eax, *ecx, regs); + + /* Only leaf 0 is supported */ + regs[0] = 0; + + /* + * Expose known-safe features. + */ + regs[1] &= (CPUID_STDEXT_FSGSBASE | + CPUID_STDEXT_BMI1 | CPUID_STDEXT_HLE | + CPUID_STDEXT_AVX2 | CPUID_STDEXT_BMI2 | + CPUID_STDEXT_ERMS | CPUID_STDEXT_RTM | + CPUID_STDEXT_AVX512F | + CPUID_STDEXT_AVX512PF | + CPUID_STDEXT_AVX512ER | + CPUID_STDEXT_AVX512CD); + regs[2] = 0; + regs[3] = 0; + + /* Advertise INVPCID if it is enabled. */ error = vm_get_capability(vm, vcpu_id, VM_CAP_ENABLE_INVPCID, &enable_invpcid); if (error == 0 && enable_invpcid) @@ -219,7 +259,6 @@ x86_emulate_cpuid(struct vm *vm, int vcpu_id, case CPUID_0000_0006: case CPUID_0000_000A: - case CPUID_0000_000D: /* * Handle the access, but report 0 for * all options @@ -240,6 +279,57 @@ x86_emulate_cpuid(struct vm *vm, int vcpu_id, regs[3] = vcpu_id; break; + case CPUID_0000_000D: + limits = vmm_get_xsave_limits(); + if (!limits->xsave_enabled) { + regs[0] = 0; + regs[1] = 0; + regs[2] = 0; + regs[3] = 0; + break; + } + + cpuid_count(*eax, *ecx, regs); + switch (*ecx) { + case 0: + /* + * Only permit the guest to use bits + * that are active in the host in + * %xcr0. Also, claim that the + * maximum save area size is + * equivalent to the host's current + * save area size. Since this runs + * "inside" of vmrun(), it runs with + * the guest's xcr0, so the current + * save area size is correct as-is. + */ + regs[0] &= limits->xcr0_allowed; + regs[2] = limits->xsave_max_size; + regs[3] &= (limits->xcr0_allowed >> 32); + break; + case 1: + /* Only permit XSAVEOPT. */ + regs[0] &= CPUID_EXTSTATE_XSAVEOPT; + regs[1] = 0; + regs[2] = 0; + regs[3] = 0; + break; + default: + /* + * If the leaf is for a permitted feature, + * pass through as-is, otherwise return + * all zeroes. + */ + if (!(limits->xcr0_allowed & (1ul << *ecx))) { + regs[0] = 0; + regs[1] = 0; + regs[2] = 0; + regs[3] = 0; + } + break; + } + break; + case 0x40000000: regs[0] = CPUID_VM_HIGH; bcopy(bhyve_id, ®s[1], 4); |
