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| author | Izik Eidus <avi@qumranet.com> | 2007-10-17 19:17:48 +0200 |
|---|---|---|
| committer | Avi Kivity <avi@qumranet.com> | 2008-01-30 17:52:54 +0200 |
| commit | cea7bb21280e3a825e64b54740edc5d3e6e4193c (patch) | |
| tree | d9714d8c13491a433951b83a176f2a04f6521009 /drivers/kvm/mmu.c | |
| parent | 9647c14c98687d0abf5197e74b9d1448ab6ebb95 (diff) | |
| download | op-kernel-dev-cea7bb21280e3a825e64b54740edc5d3e6e4193c.zip op-kernel-dev-cea7bb21280e3a825e64b54740edc5d3e6e4193c.tar.gz | |
KVM: MMU: Make gfn_to_page() always safe
In case the page is not present in the guest memory map, return a dummy
page the guest can scribble on.
This simplifies error checking in its users.
Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Diffstat (limited to 'drivers/kvm/mmu.c')
| -rw-r--r-- | drivers/kvm/mmu.c | 16 |
1 files changed, 5 insertions, 11 deletions
diff --git a/drivers/kvm/mmu.c b/drivers/kvm/mmu.c index bbf5eb4..2ad14fb 100644 --- a/drivers/kvm/mmu.c +++ b/drivers/kvm/mmu.c @@ -850,23 +850,17 @@ static void page_header_update_slot(struct kvm *kvm, void *pte, gpa_t gpa) __set_bit(slot, &page_head->slot_bitmap); } -hpa_t safe_gpa_to_hpa(struct kvm *kvm, gpa_t gpa) -{ - hpa_t hpa = gpa_to_hpa(kvm, gpa); - - return is_error_hpa(hpa) ? bad_page_address | (gpa & ~PAGE_MASK): hpa; -} - hpa_t gpa_to_hpa(struct kvm *kvm, gpa_t gpa) { struct page *page; + hpa_t hpa; ASSERT((gpa & HPA_ERR_MASK) == 0); page = gfn_to_page(kvm, gpa >> PAGE_SHIFT); - if (!page) - return gpa | HPA_ERR_MASK; - return ((hpa_t)page_to_pfn(page) << PAGE_SHIFT) - | (gpa & (PAGE_SIZE-1)); + hpa = ((hpa_t)page_to_pfn(page) << PAGE_SHIFT) | (gpa & (PAGE_SIZE-1)); + if (is_error_page(page)) + return hpa | HPA_ERR_MASK; + return hpa; } hpa_t gva_to_hpa(struct kvm_vcpu *vcpu, gva_t gva) |
