forked from luck/tmp_suning_uos_patched
[PATCH] KVM: MMU: Shadow page table caching
Define a hashtable for caching shadow page tables. Look up the cache on
context switch (cr3 change) or during page faults.
The key to the cache is a combination of
- the guest page table frame number
- the number of paging levels in the guest
* we can cache real mode, 32-bit mode, pae, and long mode page
tables simultaneously. this is useful for smp bootup.
- the guest page table table
* some kernels use a page as both a page table and a page directory. this
allows multiple shadow pages to exist for that page, one per level
- the "quadrant"
* 32-bit mode page tables span 4MB, whereas a shadow page table spans
2MB. similarly, a 32-bit page directory spans 4GB, while a shadow
page directory spans 1GB. the quadrant allows caching up to 4 shadow page
tables for one guest page in one level.
- a "metaphysical" bit
* for real mode, and for pse pages, there is no guest page table, so set
the bit to avoid write protecting the page.
Signed-off-by: Avi Kivity <avi@qumranet.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Avi Kivity
Linus Torvalds
parent
25c0de2cc6
commit
cea0f0e7ea
@ -89,14 +89,53 @@ typedef unsigned long hva_t;
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typedef u64 hpa_t;
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typedef unsigned long hfn_t;
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#define NR_PTE_CHAIN_ENTRIES 5
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struct kvm_pte_chain {
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u64 *parent_ptes[NR_PTE_CHAIN_ENTRIES];
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struct hlist_node link;
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};
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/*
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* kvm_mmu_page_role, below, is defined as:
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*
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* bits 0:3 - total guest paging levels (2-4, or zero for real mode)
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* bits 4:7 - page table level for this shadow (1-4)
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* bits 8:9 - page table quadrant for 2-level guests
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* bit 16 - "metaphysical" - gfn is not a real page (huge page/real mode)
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*/
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union kvm_mmu_page_role {
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unsigned word;
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struct {
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unsigned glevels : 4;
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unsigned level : 4;
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unsigned quadrant : 2;
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unsigned pad_for_nice_hex_output : 6;
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unsigned metaphysical : 1;
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};
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};
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struct kvm_mmu_page {
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struct list_head link;
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struct hlist_node hash_link;
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/*
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* The following two entries are used to key the shadow page in the
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* hash table.
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*/
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gfn_t gfn;
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union kvm_mmu_page_role role;
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hpa_t page_hpa;
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unsigned long slot_bitmap; /* One bit set per slot which has memory
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* in this shadow page.
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*/
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int global; /* Set if all ptes in this page are global */
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u64 *parent_pte;
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int multimapped; /* More than one parent_pte? */
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union {
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u64 *parent_pte; /* !multimapped */
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struct hlist_head parent_ptes; /* multimapped, kvm_pte_chain */
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};
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};
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struct vmcs {
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@ -235,7 +274,11 @@ struct kvm {
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spinlock_t lock; /* protects everything except vcpus */
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int nmemslots;
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struct kvm_memory_slot memslots[KVM_MEMORY_SLOTS];
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/*
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* Hash table of struct kvm_mmu_page.
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*/
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struct list_head active_mmu_pages;
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struct hlist_head mmu_page_hash[KVM_NUM_MMU_PAGES];
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struct kvm_vcpu vcpus[KVM_MAX_VCPUS];
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int memory_config_version;
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int busy;
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@ -26,8 +26,8 @@
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#include "vmx.h"
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#include "kvm.h"
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#define pgprintk(x...) do { } while (0)
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#define rmap_printk(x...) do { } while (0)
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#define pgprintk(x...) do { printk(x); } while (0)
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#define rmap_printk(x...) do { printk(x); } while (0)
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#define ASSERT(x) \
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if (!(x)) { \
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@ -35,8 +35,10 @@
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__FILE__, __LINE__, #x); \
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}
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#define PT64_ENT_PER_PAGE 512
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#define PT32_ENT_PER_PAGE 1024
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#define PT64_PT_BITS 9
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#define PT64_ENT_PER_PAGE (1 << PT64_PT_BITS)
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#define PT32_PT_BITS 10
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#define PT32_ENT_PER_PAGE (1 << PT32_PT_BITS)
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#define PT_WRITABLE_SHIFT 1
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@ -292,6 +294,11 @@ static int is_empty_shadow_page(hpa_t page_hpa)
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return 1;
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}
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static unsigned kvm_page_table_hashfn(gfn_t gfn)
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{
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return gfn;
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}
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static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu,
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u64 *parent_pte)
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{
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@ -306,10 +313,147 @@ static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu,
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ASSERT(is_empty_shadow_page(page->page_hpa));
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page->slot_bitmap = 0;
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page->global = 1;
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page->multimapped = 0;
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page->parent_pte = parent_pte;
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return page;
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}
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static void mmu_page_add_parent_pte(struct kvm_mmu_page *page, u64 *parent_pte)
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{
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struct kvm_pte_chain *pte_chain;
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struct hlist_node *node;
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int i;
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if (!parent_pte)
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return;
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if (!page->multimapped) {
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u64 *old = page->parent_pte;
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if (!old) {
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page->parent_pte = parent_pte;
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return;
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}
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page->multimapped = 1;
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pte_chain = kzalloc(sizeof(struct kvm_pte_chain), GFP_NOWAIT);
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BUG_ON(!pte_chain);
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INIT_HLIST_HEAD(&page->parent_ptes);
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hlist_add_head(&pte_chain->link, &page->parent_ptes);
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pte_chain->parent_ptes[0] = old;
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}
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hlist_for_each_entry(pte_chain, node, &page->parent_ptes, link) {
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if (pte_chain->parent_ptes[NR_PTE_CHAIN_ENTRIES-1])
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continue;
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for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i)
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if (!pte_chain->parent_ptes[i]) {
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pte_chain->parent_ptes[i] = parent_pte;
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return;
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}
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}
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pte_chain = kzalloc(sizeof(struct kvm_pte_chain), GFP_NOWAIT);
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BUG_ON(!pte_chain);
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hlist_add_head(&pte_chain->link, &page->parent_ptes);
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pte_chain->parent_ptes[0] = parent_pte;
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}
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static void mmu_page_remove_parent_pte(struct kvm_mmu_page *page,
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u64 *parent_pte)
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{
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struct kvm_pte_chain *pte_chain;
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struct hlist_node *node;
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int i;
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if (!page->multimapped) {
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BUG_ON(page->parent_pte != parent_pte);
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page->parent_pte = NULL;
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return;
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}
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hlist_for_each_entry(pte_chain, node, &page->parent_ptes, link)
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for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i) {
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if (!pte_chain->parent_ptes[i])
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break;
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if (pte_chain->parent_ptes[i] != parent_pte)
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continue;
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while (i + 1 < NR_PTE_CHAIN_ENTRIES) {
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pte_chain->parent_ptes[i]
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= pte_chain->parent_ptes[i + 1];
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++i;
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}
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pte_chain->parent_ptes[i] = NULL;
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return;
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}
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BUG();
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}
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static struct kvm_mmu_page *kvm_mmu_lookup_page(struct kvm_vcpu *vcpu,
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gfn_t gfn)
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{
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unsigned index;
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struct hlist_head *bucket;
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struct kvm_mmu_page *page;
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struct hlist_node *node;
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pgprintk("%s: looking for gfn %lx\n", __FUNCTION__, gfn);
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index = kvm_page_table_hashfn(gfn) % KVM_NUM_MMU_PAGES;
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bucket = &vcpu->kvm->mmu_page_hash[index];
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hlist_for_each_entry(page, node, bucket, hash_link)
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if (page->gfn == gfn && !page->role.metaphysical) {
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pgprintk("%s: found role %x\n",
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__FUNCTION__, page->role.word);
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return page;
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}
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return NULL;
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}
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static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
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gfn_t gfn,
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gva_t gaddr,
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unsigned level,
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int metaphysical,
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u64 *parent_pte)
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{
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union kvm_mmu_page_role role;
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unsigned index;
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unsigned quadrant;
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struct hlist_head *bucket;
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struct kvm_mmu_page *page;
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struct hlist_node *node;
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role.word = 0;
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role.glevels = vcpu->mmu.root_level;
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role.level = level;
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role.metaphysical = metaphysical;
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if (vcpu->mmu.root_level <= PT32_ROOT_LEVEL) {
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quadrant = gaddr >> (PAGE_SHIFT + (PT64_PT_BITS * level));
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quadrant &= (1 << ((PT32_PT_BITS - PT64_PT_BITS) * level)) - 1;
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role.quadrant = quadrant;
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}
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pgprintk("%s: looking gfn %lx role %x\n", __FUNCTION__,
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gfn, role.word);
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index = kvm_page_table_hashfn(gfn) % KVM_NUM_MMU_PAGES;
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bucket = &vcpu->kvm->mmu_page_hash[index];
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hlist_for_each_entry(page, node, bucket, hash_link)
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if (page->gfn == gfn && page->role.word == role.word) {
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mmu_page_add_parent_pte(page, parent_pte);
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pgprintk("%s: found\n", __FUNCTION__);
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return page;
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}
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page = kvm_mmu_alloc_page(vcpu, parent_pte);
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if (!page)
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return page;
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pgprintk("%s: adding gfn %lx role %x\n", __FUNCTION__, gfn, role.word);
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page->gfn = gfn;
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page->role = role;
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hlist_add_head(&page->hash_link, bucket);
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return page;
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}
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static void kvm_mmu_put_page(struct kvm_vcpu *vcpu,
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struct kvm_mmu_page *page,
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u64 *parent_pte)
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{
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mmu_page_remove_parent_pte(page, parent_pte);
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}
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static void page_header_update_slot(struct kvm *kvm, void *pte, gpa_t gpa)
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{
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int slot = memslot_id(kvm, gfn_to_memslot(kvm, gpa >> PAGE_SHIFT));
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@ -389,11 +533,15 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, hpa_t p)
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for (; ; level--) {
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u32 index = PT64_INDEX(v, level);
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u64 *table;
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u64 pte;
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ASSERT(VALID_PAGE(table_addr));
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table = __va(table_addr);
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if (level == 1) {
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pte = table[index];
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if (is_present_pte(pte) && is_writeble_pte(pte))
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return 0;
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mark_page_dirty(vcpu->kvm, v >> PAGE_SHIFT);
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page_header_update_slot(vcpu->kvm, table, v);
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table[index] = p | PT_PRESENT_MASK | PT_WRITABLE_MASK |
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@ -404,8 +552,13 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, hpa_t p)
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if (table[index] == 0) {
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struct kvm_mmu_page *new_table;
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gfn_t pseudo_gfn;
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new_table = kvm_mmu_alloc_page(vcpu, &table[index]);
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pseudo_gfn = (v & PT64_DIR_BASE_ADDR_MASK)
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>> PAGE_SHIFT;
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new_table = kvm_mmu_get_page(vcpu, pseudo_gfn,
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v, level - 1,
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1, &table[index]);
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if (!new_table) {
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pgprintk("nonpaging_map: ENOMEM\n");
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return -ENOMEM;
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@ -427,7 +580,6 @@ static void mmu_free_roots(struct kvm_vcpu *vcpu)
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hpa_t root = vcpu->mmu.root_hpa;
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ASSERT(VALID_PAGE(root));
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release_pt_page_64(vcpu, root, PT64_ROOT_LEVEL);
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vcpu->mmu.root_hpa = INVALID_PAGE;
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return;
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}
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@ -437,7 +589,6 @@ static void mmu_free_roots(struct kvm_vcpu *vcpu)
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ASSERT(VALID_PAGE(root));
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root &= PT64_BASE_ADDR_MASK;
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release_pt_page_64(vcpu, root, PT32E_ROOT_LEVEL - 1);
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vcpu->mmu.pae_root[i] = INVALID_PAGE;
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}
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vcpu->mmu.root_hpa = INVALID_PAGE;
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@ -446,13 +597,16 @@ static void mmu_free_roots(struct kvm_vcpu *vcpu)
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static void mmu_alloc_roots(struct kvm_vcpu *vcpu)
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{
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int i;
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gfn_t root_gfn;
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root_gfn = vcpu->cr3 >> PAGE_SHIFT;
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#ifdef CONFIG_X86_64
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if (vcpu->mmu.shadow_root_level == PT64_ROOT_LEVEL) {
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hpa_t root = vcpu->mmu.root_hpa;
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ASSERT(!VALID_PAGE(root));
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root = kvm_mmu_alloc_page(vcpu, NULL)->page_hpa;
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root = kvm_mmu_get_page(vcpu, root_gfn, 0,
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PT64_ROOT_LEVEL, 0, NULL)->page_hpa;
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vcpu->mmu.root_hpa = root;
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return;
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}
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@ -461,7 +615,13 @@ static void mmu_alloc_roots(struct kvm_vcpu *vcpu)
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hpa_t root = vcpu->mmu.pae_root[i];
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ASSERT(!VALID_PAGE(root));
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root = kvm_mmu_alloc_page(vcpu, NULL)->page_hpa;
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if (vcpu->mmu.root_level == PT32E_ROOT_LEVEL)
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root_gfn = vcpu->pdptrs[i] >> PAGE_SHIFT;
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else if (vcpu->mmu.root_level == 0)
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root_gfn = 0;
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root = kvm_mmu_get_page(vcpu, root_gfn, i << 30,
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PT32_ROOT_LEVEL, !is_paging(vcpu),
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NULL)->page_hpa;
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vcpu->mmu.pae_root[i] = root | PT_PRESENT_MASK;
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}
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vcpu->mmu.root_hpa = __pa(vcpu->mmu.pae_root);
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@ -529,7 +689,7 @@ static int nonpaging_init_context(struct kvm_vcpu *vcpu)
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context->inval_page = nonpaging_inval_page;
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context->gva_to_gpa = nonpaging_gva_to_gpa;
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context->free = nonpaging_free;
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context->root_level = PT32E_ROOT_LEVEL;
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context->root_level = 0;
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context->shadow_root_level = PT32E_ROOT_LEVEL;
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mmu_alloc_roots(vcpu);
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ASSERT(VALID_PAGE(context->root_hpa));
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@ -537,29 +697,18 @@ static int nonpaging_init_context(struct kvm_vcpu *vcpu)
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return 0;
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}
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static void kvm_mmu_flush_tlb(struct kvm_vcpu *vcpu)
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{
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struct kvm_mmu_page *page, *npage;
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list_for_each_entry_safe(page, npage, &vcpu->kvm->active_mmu_pages,
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link) {
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if (page->global)
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continue;
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if (!page->parent_pte)
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continue;
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*page->parent_pte = 0;
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release_pt_page_64(vcpu, page->page_hpa, 1);
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}
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++kvm_stat.tlb_flush;
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kvm_arch_ops->tlb_flush(vcpu);
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}
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static void paging_new_cr3(struct kvm_vcpu *vcpu)
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{
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mmu_free_roots(vcpu);
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mmu_alloc_roots(vcpu);
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kvm_mmu_flush_tlb(vcpu);
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kvm_arch_ops->set_cr3(vcpu, vcpu->mmu.root_hpa);
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}
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static void mark_pagetable_nonglobal(void *shadow_pte)
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@ -578,6 +727,16 @@ static inline void set_pte_common(struct kvm_vcpu *vcpu,
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*shadow_pte |= access_bits << PT_SHADOW_BITS_OFFSET;
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if (!dirty)
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access_bits &= ~PT_WRITABLE_MASK;
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if (access_bits & PT_WRITABLE_MASK) {
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struct kvm_mmu_page *shadow;
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shadow = kvm_mmu_lookup_page(vcpu, gaddr >> PAGE_SHIFT);
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if (shadow)
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pgprintk("%s: found shadow page for %lx, marking ro\n",
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__FUNCTION__, (gfn_t)(gaddr >> PAGE_SHIFT));
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if (shadow)
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access_bits &= ~PT_WRITABLE_MASK;
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}
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if (access_bits & PT_WRITABLE_MASK)
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mark_page_dirty(vcpu->kvm, gaddr >> PAGE_SHIFT);
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@ -32,6 +32,11 @@
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#define SHADOW_PT_INDEX(addr, level) PT64_INDEX(addr, level)
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#define PT_LEVEL_MASK(level) PT64_LEVEL_MASK(level)
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#define PT_PTE_COPY_MASK PT64_PTE_COPY_MASK
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#ifdef CONFIG_X86_64
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#define PT_MAX_FULL_LEVELS 4
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#else
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#define PT_MAX_FULL_LEVELS 2
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#endif
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#elif PTTYPE == 32
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#define pt_element_t u32
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#define guest_walker guest_walker32
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@ -42,6 +47,7 @@
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#define SHADOW_PT_INDEX(addr, level) PT64_INDEX(addr, level)
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#define PT_LEVEL_MASK(level) PT32_LEVEL_MASK(level)
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#define PT_PTE_COPY_MASK PT32_PTE_COPY_MASK
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#define PT_MAX_FULL_LEVELS 2
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#else
|
||||
#error Invalid PTTYPE value
|
||||
#endif
|
||||
@ -52,7 +58,7 @@
|
||||
*/
|
||||
struct guest_walker {
|
||||
int level;
|
||||
gfn_t table_gfn;
|
||||
gfn_t table_gfn[PT_MAX_FULL_LEVELS];
|
||||
pt_element_t *table;
|
||||
pt_element_t *ptep;
|
||||
pt_element_t inherited_ar;
|
||||
@ -68,7 +74,9 @@ static void FNAME(walk_addr)(struct guest_walker *walker,
|
||||
struct kvm_memory_slot *slot;
|
||||
pt_element_t *ptep;
|
||||
pt_element_t root;
|
||||
gfn_t table_gfn;
|
||||
|
||||
pgprintk("%s: addr %lx\n", __FUNCTION__, addr);
|
||||
walker->level = vcpu->mmu.root_level;
|
||||
walker->table = NULL;
|
||||
root = vcpu->cr3;
|
||||
@ -81,8 +89,11 @@ static void FNAME(walk_addr)(struct guest_walker *walker,
|
||||
--walker->level;
|
||||
}
|
||||
#endif
|
||||
walker->table_gfn = (root & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT;
|
||||
slot = gfn_to_memslot(vcpu->kvm, walker->table_gfn);
|
||||
table_gfn = (root & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT;
|
||||
walker->table_gfn[walker->level - 1] = table_gfn;
|
||||
pgprintk("%s: table_gfn[%d] %lx\n", __FUNCTION__,
|
||||
walker->level - 1, table_gfn);
|
||||
slot = gfn_to_memslot(vcpu->kvm, table_gfn);
|
||||
hpa = safe_gpa_to_hpa(vcpu, root & PT64_BASE_ADDR_MASK);
|
||||
walker->table = kmap_atomic(pfn_to_page(hpa >> PAGE_SHIFT), KM_USER0);
|
||||
|
||||
@ -111,12 +122,15 @@ static void FNAME(walk_addr)(struct guest_walker *walker,
|
||||
|
||||
if (walker->level != 3 || is_long_mode(vcpu))
|
||||
walker->inherited_ar &= walker->table[index];
|
||||
walker->table_gfn = (*ptep & PT_BASE_ADDR_MASK) >> PAGE_SHIFT;
|
||||
table_gfn = (*ptep & PT_BASE_ADDR_MASK) >> PAGE_SHIFT;
|
||||
paddr = safe_gpa_to_hpa(vcpu, *ptep & PT_BASE_ADDR_MASK);
|
||||
kunmap_atomic(walker->table, KM_USER0);
|
||||
walker->table = kmap_atomic(pfn_to_page(paddr >> PAGE_SHIFT),
|
||||
KM_USER0);
|
||||
--walker->level;
|
||||
walker->table_gfn[walker->level - 1 ] = table_gfn;
|
||||
pgprintk("%s: table_gfn[%d] %lx\n", __FUNCTION__,
|
||||
walker->level - 1, table_gfn);
|
||||
}
|
||||
walker->ptep = ptep;
|
||||
}
|
||||
@ -181,6 +195,8 @@ static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
|
||||
u64 *shadow_ent = ((u64 *)__va(shadow_addr)) + index;
|
||||
struct kvm_mmu_page *shadow_page;
|
||||
u64 shadow_pte;
|
||||
int metaphysical;
|
||||
gfn_t table_gfn;
|
||||
|
||||
if (is_present_pte(*shadow_ent) || is_io_pte(*shadow_ent)) {
|
||||
if (level == PT_PAGE_TABLE_LEVEL)
|
||||
@ -205,7 +221,17 @@ static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
|
||||
return shadow_ent;
|
||||
}
|
||||
|
||||
shadow_page = kvm_mmu_alloc_page(vcpu, shadow_ent);
|
||||
if (level - 1 == PT_PAGE_TABLE_LEVEL
|
||||
&& walker->level == PT_DIRECTORY_LEVEL) {
|
||||
metaphysical = 1;
|
||||
table_gfn = (*guest_ent & PT_BASE_ADDR_MASK)
|
||||
>> PAGE_SHIFT;
|
||||
} else {
|
||||
metaphysical = 0;
|
||||
table_gfn = walker->table_gfn[level - 2];
|
||||
}
|
||||
shadow_page = kvm_mmu_get_page(vcpu, table_gfn, addr, level-1,
|
||||
metaphysical, shadow_ent);
|
||||
if (!shadow_page)
|
||||
return ERR_PTR(-ENOMEM);
|
||||
shadow_addr = shadow_page->page_hpa;
|
||||
@ -227,7 +253,8 @@ static int FNAME(fix_write_pf)(struct kvm_vcpu *vcpu,
|
||||
u64 *shadow_ent,
|
||||
struct guest_walker *walker,
|
||||
gva_t addr,
|
||||
int user)
|
||||
int user,
|
||||
int *write_pt)
|
||||
{
|
||||
pt_element_t *guest_ent;
|
||||
int writable_shadow;
|
||||
@ -264,6 +291,12 @@ static int FNAME(fix_write_pf)(struct kvm_vcpu *vcpu,
|
||||
}
|
||||
|
||||
gfn = (*guest_ent & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT;
|
||||
if (kvm_mmu_lookup_page(vcpu, gfn)) {
|
||||
pgprintk("%s: found shadow page for %lx, marking ro\n",
|
||||
__FUNCTION__, gfn);
|
||||
*write_pt = 1;
|
||||
return 0;
|
||||
}
|
||||
mark_page_dirty(vcpu->kvm, gfn);
|
||||
*shadow_ent |= PT_WRITABLE_MASK;
|
||||
*guest_ent |= PT_DIRTY_MASK;
|
||||
@ -294,7 +327,9 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr,
|
||||
struct guest_walker walker;
|
||||
u64 *shadow_pte;
|
||||
int fixed;
|
||||
int write_pt = 0;
|
||||
|
||||
pgprintk("%s: addr %lx err %x\n", __FUNCTION__, addr, error_code);
|
||||
/*
|
||||
* Look up the shadow pte for the faulting address.
|
||||
*/
|
||||
@ -302,6 +337,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr,
|
||||
FNAME(walk_addr)(&walker, vcpu, addr);
|
||||
shadow_pte = FNAME(fetch)(vcpu, addr, &walker);
|
||||
if (IS_ERR(shadow_pte)) { /* must be -ENOMEM */
|
||||
printk("%s: oom\n", __FUNCTION__);
|
||||
nonpaging_flush(vcpu);
|
||||
FNAME(release_walker)(&walker);
|
||||
continue;
|
||||
@ -313,20 +349,27 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr,
|
||||
* The page is not mapped by the guest. Let the guest handle it.
|
||||
*/
|
||||
if (!shadow_pte) {
|
||||
pgprintk("%s: not mapped\n", __FUNCTION__);
|
||||
inject_page_fault(vcpu, addr, error_code);
|
||||
FNAME(release_walker)(&walker);
|
||||
return 0;
|
||||
}
|
||||
|
||||
pgprintk("%s: shadow pte %p %llx\n", __FUNCTION__,
|
||||
shadow_pte, *shadow_pte);
|
||||
|
||||
/*
|
||||
* Update the shadow pte.
|
||||
*/
|
||||
if (write_fault)
|
||||
fixed = FNAME(fix_write_pf)(vcpu, shadow_pte, &walker, addr,
|
||||
user_fault);
|
||||
user_fault, &write_pt);
|
||||
else
|
||||
fixed = fix_read_pf(shadow_pte);
|
||||
|
||||
pgprintk("%s: updated shadow pte %p %llx\n", __FUNCTION__,
|
||||
shadow_pte, *shadow_pte);
|
||||
|
||||
FNAME(release_walker)(&walker);
|
||||
|
||||
/*
|
||||
@ -344,14 +387,14 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr,
|
||||
/*
|
||||
* pte not present, guest page fault.
|
||||
*/
|
||||
if (pte_present && !fixed) {
|
||||
if (pte_present && !fixed && !write_pt) {
|
||||
inject_page_fault(vcpu, addr, error_code);
|
||||
return 0;
|
||||
}
|
||||
|
||||
++kvm_stat.pf_fixed;
|
||||
|
||||
return 0;
|
||||
return write_pt;
|
||||
}
|
||||
|
||||
static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t vaddr)
|
||||
@ -395,3 +438,4 @@ static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t vaddr)
|
||||
#undef PT_PTE_COPY_MASK
|
||||
#undef PT_NON_PTE_COPY_MASK
|
||||
#undef PT_DIR_BASE_ADDR_MASK
|
||||
#undef PT_MAX_FULL_LEVELS
|
||||
|
||||
Loading…
Reference in New Issue
Block a user