diff options
| -rw-r--r-- | arch/x86/include/asm/fpu/api.h | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/fpu/core.c | 38 | ||||
| -rw-r--r-- | arch/x86/kernel/fpu/xstate.c | 3 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 74 |
4 files changed, 43 insertions, 74 deletions
diff --git a/arch/x86/include/asm/fpu/api.h b/arch/x86/include/asm/fpu/api.h index d2b8603a9c7e..77a732ea4cda 100644 --- a/arch/x86/include/asm/fpu/api.h +++ b/arch/x86/include/asm/fpu/api.h @@ -116,4 +116,6 @@ extern void fpu_init_fpstate_user(struct fpu *fpu); /* KVM specific functions */ extern void fpu_swap_kvm_fpu(struct fpu *save, struct fpu *rstor, u64 restore_mask); +extern int fpu_copy_kvm_uabi_to_fpstate(struct fpu *fpu, const void *buf, u64 xcr0, u32 *pkru); + #endif /* _ASM_X86_FPU_API_H */ diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 023bfe857907..65fc87760011 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -174,7 +174,43 @@ void fpu_swap_kvm_fpu(struct fpu *save, struct fpu *rstor, u64 restore_mask) fpregs_unlock(); } EXPORT_SYMBOL_GPL(fpu_swap_kvm_fpu); -#endif + +int fpu_copy_kvm_uabi_to_fpstate(struct fpu *fpu, const void *buf, u64 xcr0, + u32 *vpkru) +{ + union fpregs_state *kstate = &fpu->state; + const union fpregs_state *ustate = buf; + struct pkru_state *xpkru; + int ret; + + if (!cpu_feature_enabled(X86_FEATURE_XSAVE)) { + if (ustate->xsave.header.xfeatures & ~XFEATURE_MASK_FPSSE) + return -EINVAL; + if (ustate->fxsave.mxcsr & ~mxcsr_feature_mask) + return -EINVAL; + memcpy(&kstate->fxsave, &ustate->fxsave, sizeof(ustate->fxsave)); + return 0; + } + + if (ustate->xsave.header.xfeatures & ~xcr0) + return -EINVAL; + + ret = copy_uabi_from_kernel_to_xstate(&kstate->xsave, ustate); + if (ret) + return ret; + + /* Retrieve PKRU if not in init state */ + if (kstate->xsave.header.xfeatures & XFEATURE_MASK_PKRU) { + xpkru = get_xsave_addr(&kstate->xsave, XFEATURE_PKRU); + *vpkru = xpkru->pkru; + } + + /* Ensure that XCOMP_BV is set up for XSAVES */ + xstate_init_xcomp_bv(&kstate->xsave, xfeatures_mask_uabi()); + return 0; +} +EXPORT_SYMBOL_GPL(fpu_copy_kvm_uabi_to_fpstate); +#endif /* CONFIG_KVM */ void kernel_fpu_begin_mask(unsigned int kfpu_mask) { diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index 68355605ca75..eeeb807b9717 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -1134,8 +1134,7 @@ static int copy_uabi_to_xstate(struct xregs_state *xsave, const void *kbuf, /* * Convert from a ptrace standard-format kernel buffer to kernel XSAVE[S] - * format and copy to the target thread. This is called from - * xstateregs_set(). + * format and copy to the target thread. Used by ptrace and KVM. */ int copy_uabi_from_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf) { diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 66eea4e314db..cdc19b1d5775 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4702,8 +4702,6 @@ static int kvm_vcpu_ioctl_x86_set_debugregs(struct kvm_vcpu *vcpu, return 0; } -#define XSTATE_COMPACTION_ENABLED (1ULL << 63) - static void fill_xsave(u8 *dest, struct kvm_vcpu *vcpu) { struct xregs_state *xsave = &vcpu->arch.guest_fpu->state.xsave; @@ -4747,50 +4745,6 @@ static void fill_xsave(u8 *dest, struct kvm_vcpu *vcpu) } } -static void load_xsave(struct kvm_vcpu *vcpu, u8 *src) -{ - struct xregs_state *xsave = &vcpu->arch.guest_fpu->state.xsave; - u64 xstate_bv = *(u64 *)(src + XSAVE_HDR_OFFSET); - u64 valid; - - /* - * Copy legacy XSAVE area, to avoid complications with CPUID - * leaves 0 and 1 in the loop below. - */ - memcpy(xsave, src, XSAVE_HDR_OFFSET); - - /* Set XSTATE_BV and possibly XCOMP_BV. */ - xsave->header.xfeatures = xstate_bv; - if (boot_cpu_has(X86_FEATURE_XSAVES)) - xsave->header.xcomp_bv = host_xcr0 | XSTATE_COMPACTION_ENABLED; - - /* - * Copy each region from the non-compacted offset to the - * possibly compacted offset. - */ - valid = xstate_bv & ~XFEATURE_MASK_FPSSE; - while (valid) { - u32 size, offset, ecx, edx; - u64 xfeature_mask = valid & -valid; - int xfeature_nr = fls64(xfeature_mask) - 1; - - cpuid_count(XSTATE_CPUID, xfeature_nr, - &size, &offset, &ecx, &edx); - - if (xfeature_nr == XFEATURE_PKRU) { - memcpy(&vcpu->arch.pkru, src + offset, - sizeof(vcpu->arch.pkru)); - } else { - void *dest = get_xsave_addr(xsave, xfeature_nr); - - if (dest) - memcpy(dest, src + offset, size); - } - - valid -= xfeature_mask; - } -} - static void kvm_vcpu_ioctl_x86_get_xsave(struct kvm_vcpu *vcpu, struct kvm_xsave *guest_xsave) { @@ -4809,37 +4763,15 @@ static void kvm_vcpu_ioctl_x86_get_xsave(struct kvm_vcpu *vcpu, } } -#define XSAVE_MXCSR_OFFSET 24 - static int kvm_vcpu_ioctl_x86_set_xsave(struct kvm_vcpu *vcpu, struct kvm_xsave *guest_xsave) { - u64 xstate_bv; - u32 mxcsr; - if (!vcpu->arch.guest_fpu) return 0; - xstate_bv = *(u64 *)&guest_xsave->region[XSAVE_HDR_OFFSET / sizeof(u32)]; - mxcsr = *(u32 *)&guest_xsave->region[XSAVE_MXCSR_OFFSET / sizeof(u32)]; - - if (boot_cpu_has(X86_FEATURE_XSAVE)) { - /* - * Here we allow setting states that are not present in - * CPUID leaf 0xD, index 0, EDX:EAX. This is for compatibility - * with old userspace. - */ - if (xstate_bv & ~supported_xcr0 || mxcsr & ~mxcsr_feature_mask) - return -EINVAL; - load_xsave(vcpu, (u8 *)guest_xsave->region); - } else { - if (xstate_bv & ~XFEATURE_MASK_FPSSE || - mxcsr & ~mxcsr_feature_mask) - return -EINVAL; - memcpy(&vcpu->arch.guest_fpu->state.fxsave, - guest_xsave->region, sizeof(struct fxregs_state)); - } - return 0; + return fpu_copy_kvm_uabi_to_fpstate(vcpu->arch.guest_fpu, + guest_xsave->region, + supported_xcr0, &vcpu->arch.pkru); } static void kvm_vcpu_ioctl_x86_get_xcrs(struct kvm_vcpu *vcpu, |