From 5f6078f9f1e32b395a78c8d0c0f6598004c668de Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Thu, 2 Jul 2020 19:35:34 -0700 Subject: [PATCH] KVM: x86/mmu: Make __GFP_ZERO a property of the memory cache Add a gfp_zero flag to 'struct kvm_mmu_memory_cache' and use it to control __GFP_ZERO instead of hardcoding a call to kmem_cache_zalloc(). A future patch needs such a flag for the __get_free_page() path, as gfn arrays do not need/want the allocator to zero the memory. Convert the kmem_cache paths to __GFP_ZERO now so as to avoid a weird and inconsistent API in the future. No functional change intended. Reviewed-by: Ben Gardon Signed-off-by: Sean Christopherson Message-Id: <20200703023545.8771-11-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/mmu/mmu.c | 7 ++++++- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 01f5c1508851..9d41eb5a8453 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -251,6 +251,7 @@ struct kvm_kernel_irq_routing_entry; */ struct kvm_mmu_memory_cache { int nobjs; + gfp_t gfp_zero; struct kmem_cache *kmem_cache; void *objects[KVM_NR_MEM_OBJS]; }; diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index a8fc17ac7ed0..6e57044ae848 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -1064,8 +1064,10 @@ static void walk_shadow_page_lockless_end(struct kvm_vcpu *vcpu) static inline void *mmu_memory_cache_alloc_obj(struct kvm_mmu_memory_cache *mc, gfp_t gfp_flags) { + gfp_flags |= mc->gfp_zero; + if (mc->kmem_cache) - return kmem_cache_zalloc(mc->kmem_cache, gfp_flags); + return kmem_cache_alloc(mc->kmem_cache, gfp_flags); else return (void *)__get_free_page(gfp_flags); } @@ -5701,7 +5703,10 @@ int kvm_mmu_create(struct kvm_vcpu *vcpu) int ret; vcpu->arch.mmu_pte_list_desc_cache.kmem_cache = pte_list_desc_cache; + vcpu->arch.mmu_pte_list_desc_cache.gfp_zero = __GFP_ZERO; + vcpu->arch.mmu_page_header_cache.kmem_cache = mmu_page_header_cache; + vcpu->arch.mmu_page_header_cache.gfp_zero = __GFP_ZERO; vcpu->arch.mmu = &vcpu->arch.root_mmu; vcpu->arch.walk_mmu = &vcpu->arch.root_mmu;