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From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Mon, 17 Jul 2017 11:14:26 +0300
Subject: KVM: x86: masking out upper bits
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Patch-mainline: v4.13-rc2
Git-commit: f85c758dbee54cc3612a6e873ef7cecdb66ebee5
References: bsc#1077761

kvm_read_cr3() returns an unsigned long and gfn is a u64.  We intended
to mask out the bottom 5 bits but because of the type issue we mask the
top 32 bits as well.  I don't know if this is a real problem, but it
causes static checker warnings.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Acked-by: Alexander Graf <agraf@suse.de>
---
 arch/x86/kvm/x86.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -598,8 +598,8 @@
 		      (unsigned long *)&vcpu->arch.regs_avail))
 		return true;
 
-	gfn = (kvm_read_cr3(vcpu) & ~31u) >> PAGE_SHIFT;
-	offset = (kvm_read_cr3(vcpu) & ~31u) & (PAGE_SIZE - 1);
+	gfn = (kvm_read_cr3(vcpu) & ~31ul) >> PAGE_SHIFT;
+	offset = (kvm_read_cr3(vcpu) & ~31ul) & (PAGE_SIZE - 1);
 	r = kvm_read_nested_guest_page(vcpu, gfn, pdpte, offset, sizeof(pdpte),
 				       PFERR_USER_MASK | PFERR_WRITE_MASK);
 	if (r < 0)