On 09/02/2010 06:29 PM, Joerg Roedel wrote:
This patch fixes 32 bit legacy paging with NPT enabled. The
mmu_check_root call on the top-level of the loop causes
root_gfn to take values (in the tdp_enabled path) which are
outside of guest memory. So the mmu_check_root call fails at
some point in the loop interation causing the guest to
tiple-fault.
This patch changes the mmu_check_root calls to the places
where they are really necessary. As a side-effect it
introduces a check for the root of a pae page table too.
@@ -2387,6 +2387,10 @@ static int mmu_alloc_roots(struct kvm_vcpu *vcpu)
return 0;
}
direct = !is_paging(vcpu);
+
+ if (mmu_check_root(vcpu, root_gfn))
+ return 1;
+
for (i = 0; i< 4; ++i) {
hpa_t root = vcpu->arch.mmu.pae_root[i];
@@ -2398,10 +2402,10 @@ static int mmu_alloc_roots(struct kvm_vcpu *vcpu)
continue;
}
root_gfn = pdptr>> PAGE_SHIFT;
+ if (mmu_check_root(vcpu, root_gfn))
+ return 1;
} else if (vcpu->arch.mmu.root_level == 0)
root_gfn = 0;
- if (mmu_check_root(vcpu, root_gfn))
- return 1;
if (tdp_enabled) {
direct = 1;
root_gfn = i<< 30;
The overloading of root_gfn is pretty bad. Also, we don't really need
to check root_gfn for the direct case (the guest can easily switch cr3
later to one that would fail the check).
However, I'll apply the patch since it fixes the direct problem. More
involved fixes can come later (esp. after the nnpt patches land).
--
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
