Both Christoph Hellwig and Jason Gunthorpe suggested that usage of follow_pfn by modules should be locked down more. To do so callers need to be able to pass the mmu_notifier subscription corresponding to the mm_struct to follow_pfn().
This patch does the rote work of doing that in the kvm subsystem. In most places this is solved by passing struct kvm * down the call stacks as an additional parameter, since that contains the mmu_notifier.
Compile tested on all affected arch.
Acked-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Daniel Vetter daniel.vetter@intel.com Cc: Christoph Hellwig hch@infradead.org Cc: Jason Gunthorpe jgg@ziepe.ca Cc: Kees Cook keescook@chromium.org Cc: Dan Williams dan.j.williams@intel.com Cc: Andrew Morton akpm@linux-foundation.org Cc: John Hubbard jhubbard@nvidia.com Cc: Jérôme Glisse jglisse@redhat.com Cc: Jan Kara jack@suse.cz Cc: Dan Williams dan.j.williams@intel.com Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-samsung-soc@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: kvm@vger.kernel.org Signed-off-by: Daniel Vetter daniel.vetter@ffwll.ch --- arch/powerpc/kvm/book3s_64_mmu_hv.c | 2 +- arch/powerpc/kvm/book3s_64_mmu_radix.c | 2 +- arch/powerpc/kvm/e500_mmu_host.c | 2 +- arch/x86/kvm/mmu/mmu.c | 8 ++-- include/linux/kvm_host.h | 9 +++-- virt/kvm/kvm_main.c | 52 +++++++++++++++----------- 6 files changed, 45 insertions(+), 30 deletions(-)
diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index 38ea396a23d6..86781ff76fcb 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -589,7 +589,7 @@ int kvmppc_book3s_hv_page_fault(struct kvm_vcpu *vcpu, write_ok = true; } else { /* Call KVM generic code to do the slow-path check */ - pfn = __gfn_to_pfn_memslot(memslot, gfn, false, NULL, + pfn = __gfn_to_pfn_memslot(kvm, memslot, gfn, false, NULL, writing, &write_ok); if (is_error_noslot_pfn(pfn)) return -EFAULT; diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c index bb35490400e9..319a1a99153f 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_radix.c +++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c @@ -821,7 +821,7 @@ int kvmppc_book3s_instantiate_page(struct kvm_vcpu *vcpu, unsigned long pfn;
/* Call KVM generic code to do the slow-path check */ - pfn = __gfn_to_pfn_memslot(memslot, gfn, false, NULL, + pfn = __gfn_to_pfn_memslot(kvm, memslot, gfn, false, NULL, writing, upgrade_p); if (is_error_noslot_pfn(pfn)) return -EFAULT; diff --git a/arch/powerpc/kvm/e500_mmu_host.c b/arch/powerpc/kvm/e500_mmu_host.c index ed0c9c43d0cf..fd2b2d363559 100644 --- a/arch/powerpc/kvm/e500_mmu_host.c +++ b/arch/powerpc/kvm/e500_mmu_host.c @@ -446,7 +446,7 @@ static inline int kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500,
if (likely(!pfnmap)) { tsize_pages = 1UL << (tsize + 10 - PAGE_SHIFT); - pfn = gfn_to_pfn_memslot(slot, gfn); + pfn = gfn_to_pfn_memslot(kvm, slot, gfn); if (is_error_noslot_pfn(pfn)) { if (printk_ratelimit()) pr_err("%s: real page not found for gfn %lx\n", diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 5bb1939b65d8..67ada47aa722 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -2679,7 +2679,7 @@ static kvm_pfn_t pte_prefetch_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn, if (!slot) return KVM_PFN_ERR_FAULT;
- return gfn_to_pfn_memslot_atomic(slot, gfn); + return gfn_to_pfn_memslot_atomic(vcpu->kvm, slot, gfn); }
static int direct_pte_prefetch_many(struct kvm_vcpu *vcpu, @@ -3657,7 +3657,8 @@ static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn, }
async = false; - *pfn = __gfn_to_pfn_memslot(slot, gfn, false, &async, write, writable); + *pfn = __gfn_to_pfn_memslot(vcpu->kvm, slot, gfn, + false, &async, write, writable); if (!async) return false; /* *pfn has correct page already */
@@ -3671,7 +3672,8 @@ static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn, return true; }
- *pfn = __gfn_to_pfn_memslot(slot, gfn, false, NULL, write, writable); + *pfn = __gfn_to_pfn_memslot(vcpu->kvm, slot, gfn, + false, NULL, write, writable); return false; }
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 7f2e2a09ebbd..864424ce6b6b 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -717,9 +717,12 @@ void kvm_set_page_accessed(struct page *page); kvm_pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn); kvm_pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault, bool *writable); -kvm_pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn); -kvm_pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn); -kvm_pfn_t __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn, +kvm_pfn_t gfn_to_pfn_memslot(struct kvm *kvm, + struct kvm_memory_slot *slot, gfn_t gfn); +kvm_pfn_t gfn_to_pfn_memslot_atomic(struct kvm *kvm, + struct kvm_memory_slot *slot, gfn_t gfn); +kvm_pfn_t __gfn_to_pfn_memslot(struct kvm *kvm, + struct kvm_memory_slot *slot, gfn_t gfn, bool atomic, bool *async, bool write_fault, bool *writable);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 2541a17ff1c4..417f3d470c3e 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1883,7 +1883,7 @@ static bool vma_is_valid(struct vm_area_struct *vma, bool write_fault) return true; }
-static int hva_to_pfn_remapped(struct vm_area_struct *vma, +static int hva_to_pfn_remapped(struct kvm *kvm, struct vm_area_struct *vma, unsigned long addr, bool *async, bool write_fault, bool *writable, kvm_pfn_t *p_pfn) @@ -1946,8 +1946,9 @@ static int hva_to_pfn_remapped(struct vm_area_struct *vma, * 2): @write_fault = false && @writable, @writable will tell the caller * whether the mapping is writable. */ -static kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async, - bool write_fault, bool *writable) +static kvm_pfn_t hva_to_pfn(struct kvm *kvm, unsigned long addr, + bool atomic, bool *async, + bool write_fault, bool *writable) { struct vm_area_struct *vma; kvm_pfn_t pfn = 0; @@ -1979,7 +1980,8 @@ static kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async, if (vma == NULL) pfn = KVM_PFN_ERR_FAULT; else if (vma->vm_flags & (VM_IO | VM_PFNMAP)) { - r = hva_to_pfn_remapped(vma, addr, async, write_fault, writable, &pfn); + r = hva_to_pfn_remapped(kvm, vma, addr, + async, write_fault, writable, &pfn); if (r == -EAGAIN) goto retry; if (r < 0) @@ -1994,7 +1996,8 @@ static kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async, return pfn; }
-kvm_pfn_t __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn, +kvm_pfn_t __gfn_to_pfn_memslot(struct kvm *kvm, + struct kvm_memory_slot *slot, gfn_t gfn, bool atomic, bool *async, bool write_fault, bool *writable) { @@ -2018,7 +2021,7 @@ kvm_pfn_t __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn, writable = NULL; }
- return hva_to_pfn(addr, atomic, async, write_fault, + return hva_to_pfn(kvm, addr, atomic, async, write_fault, writable); } EXPORT_SYMBOL_GPL(__gfn_to_pfn_memslot); @@ -2026,38 +2029,43 @@ EXPORT_SYMBOL_GPL(__gfn_to_pfn_memslot); kvm_pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault, bool *writable) { - return __gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn, false, NULL, + return __gfn_to_pfn_memslot(kvm, gfn_to_memslot(kvm, gfn), gfn, + false, NULL, write_fault, writable); } EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);
-kvm_pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn) +kvm_pfn_t gfn_to_pfn_memslot(struct kvm *kvm, + struct kvm_memory_slot *slot, gfn_t gfn) { - return __gfn_to_pfn_memslot(slot, gfn, false, NULL, true, NULL); + return __gfn_to_pfn_memslot(kvm, slot, gfn, false, NULL, true, NULL); } EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot);
-kvm_pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn) +kvm_pfn_t gfn_to_pfn_memslot_atomic(struct kvm *kvm, + struct kvm_memory_slot *slot, gfn_t gfn) { - return __gfn_to_pfn_memslot(slot, gfn, true, NULL, true, NULL); + return __gfn_to_pfn_memslot(kvm, slot, gfn, true, NULL, true, NULL); } EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic);
kvm_pfn_t kvm_vcpu_gfn_to_pfn_atomic(struct kvm_vcpu *vcpu, gfn_t gfn) { - return gfn_to_pfn_memslot_atomic(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn); + return gfn_to_pfn_memslot_atomic(vcpu->kvm, + kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn); } EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn_atomic);
kvm_pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn) { - return gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn); + return gfn_to_pfn_memslot(kvm, gfn_to_memslot(kvm, gfn), gfn); } EXPORT_SYMBOL_GPL(gfn_to_pfn);
kvm_pfn_t kvm_vcpu_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn) { - return gfn_to_pfn_memslot(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn); + return gfn_to_pfn_memslot(vcpu->kvm, + kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn); } EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn);
@@ -2115,18 +2123,20 @@ void kvm_release_pfn(kvm_pfn_t pfn, bool dirty, struct gfn_to_pfn_cache *cache) kvm_release_pfn_clean(pfn); }
-static void kvm_cache_gfn_to_pfn(struct kvm_memory_slot *slot, gfn_t gfn, +static void kvm_cache_gfn_to_pfn(struct kvm *kvm, + struct kvm_memory_slot *slot, gfn_t gfn, struct gfn_to_pfn_cache *cache, u64 gen) { kvm_release_pfn(cache->pfn, cache->dirty, cache);
- cache->pfn = gfn_to_pfn_memslot(slot, gfn); + cache->pfn = gfn_to_pfn_memslot(kvm, slot, gfn); cache->gfn = gfn; cache->dirty = false; cache->generation = gen; }
-static int __kvm_map_gfn(struct kvm_memslots *slots, gfn_t gfn, +static int __kvm_map_gfn(struct kvm *kvm, + struct kvm_memslots *slots, gfn_t gfn, struct kvm_host_map *map, struct gfn_to_pfn_cache *cache, bool atomic) @@ -2145,13 +2155,13 @@ static int __kvm_map_gfn(struct kvm_memslots *slots, gfn_t gfn, cache->generation != gen) { if (atomic) return -EAGAIN; - kvm_cache_gfn_to_pfn(slot, gfn, cache, gen); + kvm_cache_gfn_to_pfn(kvm, slot, gfn, cache, gen); } pfn = cache->pfn; } else { if (atomic) return -EAGAIN; - pfn = gfn_to_pfn_memslot(slot, gfn); + pfn = gfn_to_pfn_memslot(kvm, slot, gfn); } if (is_error_noslot_pfn(pfn)) return -EINVAL; @@ -2184,14 +2194,14 @@ static int __kvm_map_gfn(struct kvm_memslots *slots, gfn_t gfn, int kvm_map_gfn(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map, struct gfn_to_pfn_cache *cache, bool atomic) { - return __kvm_map_gfn(kvm_memslots(vcpu->kvm), gfn, map, + return __kvm_map_gfn(vcpu->kvm, kvm_memslots(vcpu->kvm), gfn, map, cache, atomic); } EXPORT_SYMBOL_GPL(kvm_map_gfn);
int kvm_vcpu_map(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map) { - return __kvm_map_gfn(kvm_vcpu_memslots(vcpu), gfn, map, + return __kvm_map_gfn(vcpu->kvm, kvm_vcpu_memslots(vcpu), gfn, map, NULL, false); } EXPORT_SYMBOL_GPL(kvm_vcpu_map);