Browse Source

Merge branch 'fixes' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Gleb Natapov.

* 'fixes' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: VMX: set "blocked by NMI" flag if EPT violation happens during IRET from NMI
  kvm: free resources after canceling async_pf
  KVM: nEPT: reset PDPTR register cache on nested vmentry emulation
  KVM: mmu: allow page tables to be in read-only slots
  KVM: x86 emulator: emulate RETF imm
master
Linus Torvalds 8 years ago
parent
commit
62d228b8c6
  1. 14
      arch/x86/kvm/emulate.c
  2. 20
      arch/x86/kvm/paging_tmpl.h
  3. 13
      arch/x86/kvm/vmx.c
  4. 1
      include/linux/kvm_host.h
  5. 5
      virt/kvm/async_pf.c
  6. 14
      virt/kvm/kvm_main.c

14
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 */

20
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;

13
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);

1
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);

5
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);

14
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();

Loading…
Cancel
Save