From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: [PATCH] account for start offset on largepage
	aligned-sized memslots
Date: Fri, 4 Apr 2008 17:21:22 -0300
Message-ID: <20080404202121.GA1763@dmt>
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Cc: kvm-devel <kvm-devel@lists.sourceforge.net>
To: Avi Kivity <avi@qumranet.com>,
	Chris Lalancette <clalance@redhat.com>
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Account for the case where memslot size is largepage aligned, but does not 
start on largepage aligned offset.

Otherwise it allocates one lpage_info struct less than what the memslot
spans, possibly resulting in memory corruption.


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


diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 3396a5f..93ed78b 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -347,6 +347,9 @@ int __kvm_set_memory_region(struct kvm *kvm,
 		int largepages = npages / KVM_PAGES_PER_HPAGE;
 		if (npages % KVM_PAGES_PER_HPAGE)
 			largepages++;
+		if (base_gfn % KVM_PAGES_PER_HPAGE)
+			largepages++;
+
 		new.lpage_info = vmalloc(largepages * sizeof(*new.lpage_info));
 
 		if (!new.lpage_info)

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