From: Marcelo Tosatti <mtosatti@redhat.com>
Date: Thu, 8 Jan 2009 19:44:19 +0000 (-0200)
Subject: KVM: MMU: drop zeroing on mmu_memory_cache_alloc
X-Git-Tag: firefly_0821_release~15239^2~44
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=9903a927a4aea4b1ea42356a8453fca664df0b18;p=firefly-linux-kernel-4.4.55.git

KVM: MMU: drop zeroing on mmu_memory_cache_alloc

Zeroing on mmu_memory_cache_alloc is unnecessary since:

- Smaller areas are pre-allocated with kmem_cache_zalloc.
- Page pointed by ->spt is overwritten with prefetch_page
  and entries in page pointed by ->gfns are initialized
  before reading.

[avi: zeroing pages is unnecessary]

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index aac0499947d8..de9a9fbc16ed 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -352,7 +352,6 @@ static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc,
 
 	BUG_ON(!mc->nobjs);
 	p = mc->objects[--mc->nobjs];
-	memset(p, 0, size);
 	return p;
 }