diff options
| -rw-r--r-- | arch/x86/kvm/emulate.c | 14 | ||||
| -rw-r--r-- | arch/x86/kvm/paging_tmpl.h | 20 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx.c | 13 | ||||
| -rw-r--r-- | include/linux/kvm_host.h | 1 | ||||
| -rw-r--r-- | virt/kvm/async_pf.c | 5 | ||||
| -rw-r--r-- | virt/kvm/kvm_main.c | 14 |
6 files changed, 59 insertions, 8 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 2bc1e81045b0..ddc3f3d2afdb 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -2025,6 +2025,17 @@ static int em_ret_far(struct x86_emulate_ctxt *ctxt) return rc; } +static int em_ret_far_imm(struct x86_emulate_ctxt *ctxt) +{ + int rc; + + rc = em_ret_far(ctxt); + if (rc != X86EMUL_CONTINUE) + return rc; + rsp_increment(ctxt, ctxt->src.val); + return X86EMUL_CONTINUE; +} + static int em_cmpxchg(struct x86_emulate_ctxt *ctxt) { /* Save real source value, then compare EAX against destination. */ @@ -3763,7 +3774,8 @@ static const struct opcode opcode_table[256] = { G(ByteOp, group11), G(0, group11), /* 0xC8 - 0xCF */ I(Stack | SrcImmU16 | Src2ImmByte, em_enter), I(Stack, em_leave), - N, I(ImplicitOps | Stack, em_ret_far), + I(ImplicitOps | Stack | SrcImmU16, em_ret_far_imm), + I(ImplicitOps | Stack, em_ret_far), D(ImplicitOps), DI(SrcImmByte, intn), D(ImplicitOps | No64), II(ImplicitOps, em_iret, iret), /* 0xD0 - 0xD7 */ diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index 043330159179..ad75d77999d0 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -99,6 +99,7 @@ struct guest_walker { pt_element_t prefetch_ptes[PTE_PREFETCH_NUM]; gpa_t pte_gpa[PT_MAX_FULL_LEVELS]; pt_element_t __user *ptep_user[PT_MAX_FULL_LEVELS]; + bool pte_writable[PT_MAX_FULL_LEVELS]; unsigned pt_access; unsigned pte_access; gfn_t gfn; @@ -235,6 +236,22 @@ static int FNAME(update_accessed_dirty_bits)(struct kvm_vcpu *vcpu, if (pte == orig_pte) continue; + /* + * If the slot is read-only, simply do not process the accessed + * and dirty bits. This is the correct thing to do if the slot + * is ROM, and page tables in read-as-ROM/write-as-MMIO slots + * are only supported if the accessed and dirty bits are already + * set in the ROM (so that MMIO writes are never needed). + * + * Note that NPT does not allow this at all and faults, since + * it always wants nested page table entries for the guest + * page tables to be writable. And EPT works but will simply + * overwrite the read-only memory to set the accessed and dirty + * bits. + */ + if (unlikely(!walker->pte_writable[level - 1])) + continue; + ret = FNAME(cmpxchg_gpte)(vcpu, mmu, ptep_user, index, orig_pte, pte); if (ret) return ret; @@ -309,7 +326,8 @@ retry_walk: goto error; real_gfn = gpa_to_gfn(real_gfn); - host_addr = gfn_to_hva(vcpu->kvm, real_gfn); + host_addr = gfn_to_hva_prot(vcpu->kvm, real_gfn, + &walker->pte_writable[walker->level - 1]); if (unlikely(kvm_is_error_hva(host_addr))) goto error; diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 1f1da43ff2a2..a1216de9ffda 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -5339,6 +5339,15 @@ static int handle_ept_violation(struct kvm_vcpu *vcpu) return 0; } + /* + * EPT violation happened while executing iret from NMI, + * "blocked by NMI" bit has to be set before next VM entry. + * There are errata that may cause this bit to not be set: + * AAK134, BY25. + */ + if (exit_qualification & INTR_INFO_UNBLOCK_NMI) + vmcs_set_bits(GUEST_INTERRUPTIBILITY_INFO, GUEST_INTR_STATE_NMI); + gpa = vmcs_read64(GUEST_PHYSICAL_ADDRESS); trace_kvm_page_fault(gpa, exit_qualification); @@ -7766,6 +7775,10 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12) vmcs_write64(GUEST_PDPTR1, vmcs12->guest_pdptr1); vmcs_write64(GUEST_PDPTR2, vmcs12->guest_pdptr2); vmcs_write64(GUEST_PDPTR3, vmcs12->guest_pdptr3); + __clear_bit(VCPU_EXREG_PDPTR, + (unsigned long *)&vcpu->arch.regs_avail); + __clear_bit(VCPU_EXREG_PDPTR, + (unsigned long *)&vcpu->arch.regs_dirty); } kvm_register_write(vcpu, VCPU_REGS_RSP, vmcs12->guest_rsp); diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index ca645a01d37a..0fbbc7aa02cb 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -533,6 +533,7 @@ int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages, struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn); unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn); +unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable); unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot, gfn_t gfn); void kvm_release_page_clean(struct page *page); void kvm_release_page_dirty(struct page *page); diff --git a/virt/kvm/async_pf.c b/virt/kvm/async_pf.c index ea475cd03511..8a39dda7a325 100644 --- a/virt/kvm/async_pf.c +++ b/virt/kvm/async_pf.c @@ -101,8 +101,11 @@ void kvm_clear_async_pf_completion_queue(struct kvm_vcpu *vcpu) typeof(*work), queue); cancel_work_sync(&work->work); list_del(&work->queue); - if (!work->done) /* work was canceled */ + if (!work->done) { /* work was canceled */ + mmdrop(work->mm); + kvm_put_kvm(vcpu->kvm); /* == work->vcpu->kvm */ kmem_cache_free(async_pf_cache, work); + } } spin_lock(&vcpu->async_pf.lock); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index bf040c4e02b3..979bff485fb0 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1058,11 +1058,15 @@ unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn) EXPORT_SYMBOL_GPL(gfn_to_hva); /* - * The hva returned by this function is only allowed to be read. - * It should pair with kvm_read_hva() or kvm_read_hva_atomic(). + * If writable is set to false, the hva returned by this function is only + * allowed to be read. */ -static unsigned long gfn_to_hva_read(struct kvm *kvm, gfn_t gfn) +unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable) { + struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn); + if (writable) + *writable = !memslot_is_readonly(slot); + return __gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL, false); } @@ -1430,7 +1434,7 @@ int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset, int r; unsigned long addr; - addr = gfn_to_hva_read(kvm, gfn); + addr = gfn_to_hva_prot(kvm, gfn, NULL); if (kvm_is_error_hva(addr)) return -EFAULT; r = kvm_read_hva(data, (void __user *)addr + offset, len); @@ -1468,7 +1472,7 @@ int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data, gfn_t gfn = gpa >> PAGE_SHIFT; int offset = offset_in_page(gpa); - addr = gfn_to_hva_read(kvm, gfn); + addr = gfn_to_hva_prot(kvm, gfn, NULL); if (kvm_is_error_hva(addr)) return -EFAULT; pagefault_disable(); |