From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: KVM: SVM: remove needless mmap_sem acquision from nested_svm_map
Date: Tue, 8 Sep 2009 14:47:38 -0300
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Cc: Alexander Graf <agraf@suse.de>
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nested_svm_map unnecessarily takes mmap_sem around gfn_to_page, since
gfn_to_page / get_user_pages are responsible for it.

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

Index: kvm/arch/x86/kvm/svm.c
===================================================================
--- kvm.orig/arch/x86/kvm/svm.c
+++ kvm/arch/x86/kvm/svm.c
@@ -1394,10 +1394,7 @@ static void *nested_svm_map(struct vcpu_
 {
 	struct page *page;
 
-	down_read(&current->mm->mmap_sem);
 	page = gfn_to_page(svm->vcpu.kvm, gpa >> PAGE_SHIFT);
-	up_read(&current->mm->mmap_sem);
-
 	if (is_error_page(page))
 		goto error;