diff options
Diffstat (limited to 'sys/amd64/vmm/vmm_host.c')
| -rw-r--r-- | sys/amd64/vmm/vmm_host.c | 39 |
1 files changed, 38 insertions, 1 deletions
diff --git a/sys/amd64/vmm/vmm_host.c b/sys/amd64/vmm/vmm_host.c index 8dfef73..9e5b966 100644 --- a/sys/amd64/vmm/vmm_host.c +++ b/sys/amd64/vmm/vmm_host.c @@ -38,11 +38,14 @@ __FBSDID("$FreeBSD$"); #include "vmm_host.h" -static uint64_t vmm_host_efer, vmm_host_pat, vmm_host_cr0, vmm_host_cr4; +static uint64_t vmm_host_efer, vmm_host_pat, vmm_host_cr0, vmm_host_cr4, + vmm_host_xcr0; +static struct xsave_limits vmm_xsave_limits; void vmm_host_state_init(void) { + int regs[4]; vmm_host_efer = rdmsr(MSR_EFER); vmm_host_pat = rdmsr(MSR_PAT); @@ -57,6 +60,26 @@ vmm_host_state_init(void) vmm_host_cr0 = rcr0() | CR0_TS; vmm_host_cr4 = rcr4(); + + /* + * Only permit a guest to use XSAVE if the host is using + * XSAVE. Only permit a guest to use XSAVE features supported + * by the host. This ensures that the FPU state used by the + * guest is always a subset of the saved guest FPU state. + * + * In addition, only permit known XSAVE features where the + * rules for which features depend on other features is known + * to properly emulate xsetbv. + */ + if (vmm_host_cr4 & CR4_XSAVE) { + vmm_xsave_limits.xsave_enabled = 1; + vmm_host_xcr0 = rxcr(0); + vmm_xsave_limits.xcr0_allowed = vmm_host_xcr0 & + (XFEATURE_AVX | XFEATURE_MPX | XFEATURE_AVX512); + + cpuid_count(0xd, 0x0, regs); + vmm_xsave_limits.xsave_max_size = regs[1]; + } } uint64_t @@ -88,6 +111,13 @@ vmm_get_host_cr4(void) } uint64_t +vmm_get_host_xcr0(void) +{ + + return (vmm_host_xcr0); +} + +uint64_t vmm_get_host_datasel(void) { @@ -122,3 +152,10 @@ vmm_get_host_idtrbase(void) return (r_idt.rd_base); } + +const struct xsave_limits * +vmm_get_xsave_limits(void) +{ + + return (&vmm_xsave_limits); +} |
