Re: [PATCH 3/4] KVM: MMU: notrap it if gpte's reserved is set

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 11/12/2010 12:34 PM, Xiao Guangrong wrote:
We can past the page fault to guest directly if gpte's reserved
is set


How can that work? shadow_notrap_nonpresent_pte causes a fault with PFEC.P=PFEC.RSVD=0, while we need PFEC.P=PFEC.RSVD=1.

Signed-off-by: Xiao Guangrong<xiaoguangrong@xxxxxxxxxxxxxx>
---
  arch/x86/kvm/paging_tmpl.h |   10 ++++++----
  1 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index 291342d..952357a 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -760,6 +760,7 @@ static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
  		pt_element_t gpte;
  		gpa_t pte_gpa;
  		gfn_t gfn;
+		bool gpte_invalid;

  		if (!is_shadow_present_pte(sp->spt[i]))
  			continue;
@@ -771,12 +772,13 @@ static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
  			return -EINVAL;

  		gfn = gpte_to_gfn(gpte);
-		if (is_rsvd_bits_set(&vcpu->arch.mmu, gpte, PT_PAGE_TABLE_LEVEL)
-		      || gfn != sp->gfns[i] || !is_present_gpte(gpte)
-		      || !(gpte&  PT_ACCESSED_MASK)) {
+		gpte_invalid = is_present_gpte(gpte) ||
+		   is_rsvd_bits_set(&vcpu->arch.mmu, gpte, PT_PAGE_TABLE_LEVEL);

Shouldn't that be &&?

+		if (gpte_invalid || gfn != sp->gfns[i] ||
+		      !(gpte&  PT_ACCESSED_MASK)) {
  			u64 nonpresent;

-			if (is_present_gpte(gpte) || !clear_unsync)
+			if (gpte_invalid || !clear_unsync)
  				nonpresent = shadow_trap_nonpresent_pte;
  			else
  				nonpresent = shadow_notrap_nonpresent_pte;


--
error compiling committee.c: too many arguments to function

--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]
  Powered by Linux