Simplify use of the MMU page cache by allocating pages pre-zeroed. This
ensures that future code does not accidentally add non-zeroed memory to
the paging structure and moves the work of zeroing page page out from
under the MMU lock.
Signed-off-by: Ben Gardon <bgardon@xxxxxxxxxx>
---
arch/x86/kvm/mmu.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 7e5ab9c6e2b09..1ecd6d51c0ee0 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1037,7 +1037,7 @@ static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache *cache,
if (cache->nobjs >= min)
return 0;
while (cache->nobjs < ARRAY_SIZE(cache->objects)) {
- page = (void *)__get_free_page(GFP_KERNEL_ACCOUNT);
+ page = (void *)__get_free_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
if (!page)
return cache->nobjs >= min ? 0 : -ENOMEM;
cache->objects[cache->nobjs++] = page;
@@ -2548,7 +2548,6 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
if (level > PT_PAGE_TABLE_LEVEL && need_sync)
flush |= kvm_sync_pages(vcpu, gfn, &invalid_list);
}
- clear_page(sp->spt);
trace_kvm_mmu_get_page(sp, true);
kvm_mmu_flush_or_zap(vcpu, &invalid_list, false, flush);
--
2.23.0.444.g18eeb5a265-goog
