The patch titled KVM: MMU: Let the walker extract the target page gfn from the pte has been added to the -mm tree. Its filename is kvm-mmu-let-the-walker-extract-the-target-page-gfn-from-the-pte.patch See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find out what to do about this ------------------------------------------------------ Subject: KVM: MMU: Let the walker extract the target page gfn from the pte From: Avi Kivity <avi@xxxxxxxxxxxx> This fixes a problem where set_pte_common() looked for shadowed pages based on the page directory gfn (a huge page) instead of the actual gfn being mapped. Signed-off-by: Avi Kivity <avi@xxxxxxxxxxxx> Acked-by: Ingo Molnar <mingo@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxx> --- drivers/kvm/mmu.c | 7 +++--- drivers/kvm/paging_tmpl.h | 41 +++++++++++++++++++++++------------- 2 files changed, 31 insertions(+), 17 deletions(-) diff -puN drivers/kvm/mmu.c~kvm-mmu-let-the-walker-extract-the-target-page-gfn-from-the-pte drivers/kvm/mmu.c --- a/drivers/kvm/mmu.c~kvm-mmu-let-the-walker-extract-the-target-page-gfn-from-the-pte +++ a/drivers/kvm/mmu.c @@ -752,7 +752,8 @@ static inline void set_pte_common(struct u64 *shadow_pte, gpa_t gaddr, int dirty, - u64 access_bits) + u64 access_bits, + gfn_t gfn) { hpa_t paddr; @@ -779,10 +780,10 @@ static inline void set_pte_common(struct if (access_bits & PT_WRITABLE_MASK) { struct kvm_mmu_page *shadow; - shadow = kvm_mmu_lookup_page(vcpu, gaddr >> PAGE_SHIFT); + shadow = kvm_mmu_lookup_page(vcpu, gfn); if (shadow) { pgprintk("%s: found shadow page for %lx, marking ro\n", - __FUNCTION__, (gfn_t)(gaddr >> PAGE_SHIFT)); + __FUNCTION__, gfn); access_bits &= ~PT_WRITABLE_MASK; *shadow_pte &= ~PT_WRITABLE_MASK; } diff -puN drivers/kvm/paging_tmpl.h~kvm-mmu-let-the-walker-extract-the-target-page-gfn-from-the-pte drivers/kvm/paging_tmpl.h --- a/drivers/kvm/paging_tmpl.h~kvm-mmu-let-the-walker-extract-the-target-page-gfn-from-the-pte +++ a/drivers/kvm/paging_tmpl.h @@ -62,6 +62,7 @@ struct guest_walker { pt_element_t *table; pt_element_t *ptep; pt_element_t inherited_ar; + gfn_t gfn; }; /* @@ -113,12 +114,23 @@ static void FNAME(walk_addr)(struct gues if (is_present_pte(*ptep) && !(*ptep & PT_ACCESSED_MASK)) *ptep |= PT_ACCESSED_MASK; - if (!is_present_pte(*ptep) || - walker->level == PT_PAGE_TABLE_LEVEL || - (walker->level == PT_DIRECTORY_LEVEL && - (*ptep & PT_PAGE_SIZE_MASK) && - (PTTYPE == 64 || is_pse(vcpu)))) + if (!is_present_pte(*ptep)) + break; + + if (walker->level == PT_PAGE_TABLE_LEVEL) { + walker->gfn = (*ptep & PT_BASE_ADDR_MASK) + >> PAGE_SHIFT; + break; + } + + if (walker->level == PT_DIRECTORY_LEVEL + && (*ptep & PT_PAGE_SIZE_MASK) + && (PTTYPE == 64 || is_pse(vcpu))) { + walker->gfn = (*ptep & PT_DIR_BASE_ADDR_MASK) + >> PAGE_SHIFT; + walker->gfn += PT_INDEX(addr, PT_PAGE_TABLE_LEVEL); break; + } if (walker->level != 3 || is_long_mode(vcpu)) walker->inherited_ar &= walker->table[index]; @@ -143,30 +155,29 @@ static void FNAME(release_walker)(struct } static void FNAME(set_pte)(struct kvm_vcpu *vcpu, u64 guest_pte, - u64 *shadow_pte, u64 access_bits) + u64 *shadow_pte, u64 access_bits, gfn_t gfn) { ASSERT(*shadow_pte == 0); access_bits &= guest_pte; *shadow_pte = (guest_pte & PT_PTE_COPY_MASK); set_pte_common(vcpu, shadow_pte, guest_pte & PT_BASE_ADDR_MASK, - guest_pte & PT_DIRTY_MASK, access_bits); + guest_pte & PT_DIRTY_MASK, access_bits, gfn); } static void FNAME(set_pde)(struct kvm_vcpu *vcpu, u64 guest_pde, - u64 *shadow_pte, u64 access_bits, - int index) + u64 *shadow_pte, u64 access_bits, gfn_t gfn) { gpa_t gaddr; ASSERT(*shadow_pte == 0); access_bits &= guest_pde; - gaddr = (guest_pde & PT_DIR_BASE_ADDR_MASK) + PAGE_SIZE * index; + gaddr = (gpa_t)gfn << PAGE_SHIFT; if (PTTYPE == 32 && is_cpuid_PSE36()) gaddr |= (guest_pde & PT32_DIR_PSE36_MASK) << (32 - PT32_DIR_PSE36_SHIFT); *shadow_pte = guest_pde & PT_PTE_COPY_MASK; set_pte_common(vcpu, shadow_pte, gaddr, - guest_pde & PT_DIRTY_MASK, access_bits); + guest_pde & PT_DIRTY_MASK, access_bits, gfn); } /* @@ -214,10 +225,12 @@ static u64 *FNAME(fetch)(struct kvm_vcpu *prev_shadow_ent |= PT_SHADOW_PS_MARK; FNAME(set_pde)(vcpu, *guest_ent, shadow_ent, walker->inherited_ar, - PT_INDEX(addr, PT_PAGE_TABLE_LEVEL)); + walker->gfn); } else { ASSERT(walker->level == PT_PAGE_TABLE_LEVEL); - FNAME(set_pte)(vcpu, *guest_ent, shadow_ent, walker->inherited_ar); + FNAME(set_pte)(vcpu, *guest_ent, shadow_ent, + walker->inherited_ar, + walker->gfn); } return shadow_ent; } @@ -291,7 +304,7 @@ static int FNAME(fix_write_pf)(struct kv return 0; } - gfn = (*guest_ent & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT; + gfn = walker->gfn; if (kvm_mmu_lookup_page(vcpu, gfn)) { pgprintk("%s: found shadow page for %lx, marking ro\n", __FUNCTION__, gfn); _ Patches currently in -mm which might be from avi@xxxxxxxxxxxx are kvm-fix-gfp_kernel-alloc-in-atomic-section-bug.patch kvm-use-raw_smp_processor_id-instead-of-smp_processor_id-where-applicable.patch kvm-recover-after-an-arch-module-load-failure.patch kvm-improve-interrupt-response.patch kvm-prevent-stale-bits-in-cr0-and-cr4.patch kvm-mmu-implement-simple-reverse-mapping.patch kvm-mmu-teach-the-page-table-walker-to-track-guest-page-table-gfns.patch kvm-mmu-load-the-pae-pdptrs-on-cr3-change-like-the-processor-does.patch kvm-mmu-fold-fetch_guest-into-init_walker.patch kvm-mu-special-treatment-for-shadow-pae-root-pages.patch kvm-mmu-use-the-guest-pdptrs-instead-of-mapping-cr3-in-pae-mode.patch kvm-mmu-make-the-shadow-page-tables-also-special-case-pae.patch kvm-mmu-make-kvm_mmu_alloc_page-return-a-kvm_mmu_page-pointer.patch kvm-mmu-shadow-page-table-caching.patch kvm-mmu-write-protect-guest-pages-when-a-shadow-is-created-for-them.patch kvm-mmu-let-the-walker-extract-the-target-page-gfn-from-the-pte.patch kvm-mmu-support-emulated-writes-into-ram.patch kvm-mmu-zap-shadow-page-table-entries-on-writes-to-guest-page-tables.patch kvm-mmu-if-emulating-an-instruction-fails-try-unprotecting-the-page.patch kvm-mmu-implement-child-shadow-unlinking.patch kvm-mmu-kvm_mmu_put_page-only-removes-one-link-to-the-page.patch kvm-mmu-oom-handling.patch kvm-mmu-remove-invlpg-interception.patch kvm-mmu-remove-release_pt_page_64.patch kvm-mmu-handle-misaligned-accesses-to-write-protected-guest-page-tables.patch kvm-mmu-ove-is_empty_shadow_page-above-kvm_mmu_free_page.patch kvm-mmu-ensure-freed-shadow-pages-are-clean.patch kvm-mmu-if-an-empty-shadow-page-is-not-empty-report-more-info.patch kvm-mmu-page-table-write-flood-protection.patch kvm-mmu-never-free-a-shadow-page-actively-serving-as-a-root.patch kvm-mmu-fix-cmpxchg8b-emulation.patch kvm-mmu-treat-user-mode-faults-as-a-hint-that-a-page-is-no-longer-a-page-table.patch kvm-mmu-free-pages-on-kvm-destruction.patch kvm-mmu-replace-atomic-allocations-by-preallocated-objects.patch kvm-mmu-detect-oom-conditions-and-propagate-error-to-userspace.patch kvm-mmu-flush-guest-tlb-when-reducing-permissions-on-a-pte.patch kvm-mmu-destroy-mmu-while-we-still-have-a-vcpu-left.patch kvm-mmu-add-audit-code-to-check-mappings-etc-are-correct.patch - To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html