[PATCH 22/42] KVM: SVM: remove needless mmap_sem acquision from nested_svm_map

Avi Kivity
2009-11-16T12:27:48Z

From: Marcelo Tosatti <mtosatti@redhat.com>

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>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
arch/x86/kvm/svm.c | 3 ---
1 files changed, 0 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 92048a6..f54c4f9 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1396,10 +1396,7 @@ static void *nested_svm_map(struct vcpu_svm *svm, u64 gpa, enum km_type idx)
{
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;

--
1.6.5.2