linux-kernel - [PATCH 4.9 76/92] KVM: nVMX: kmap() cant fail

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Date:   Fri,  9 Feb 2018 14:39:45 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, David Hildenbrand <david@...hat.com>,
        Paolo Bonzini <pbonzini@...hat.com>
Subject: [PATCH 4.9 76/92] KVM: nVMX: kmap() cant fail

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: David Hildenbrand <david@...hat.com>

commit 42cf014d38d8822cce63703a467e00f65d000952 upstream.

kmap() can't fail, therefore it will always return a valid pointer. Let's
just get rid of the unnecessary checks.

Signed-off-by: David Hildenbrand <david@...hat.com>
Signed-off-by: Paolo Bonzini <pbonzini@...hat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 arch/x86/kvm/vmx.c |    9 ---------
 1 file changed, 9 deletions(-)

--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -4756,10 +4756,6 @@ static int vmx_complete_nested_posted_in
 			return 0;
 
 		vapic_page = kmap(vmx->nested.virtual_apic_page);
-		if (!vapic_page) {
-			WARN_ON(1);
-			return -ENOMEM;
-		}
 		__kvm_apic_update_irr(vmx->nested.pi_desc->pir, vapic_page);
 		kunmap(vmx->nested.virtual_apic_page);
 
@@ -9584,11 +9580,6 @@ static inline bool nested_vmx_merge_msr_
 	if (!page)
 		return false;
 	msr_bitmap_l1 = (unsigned long *)kmap(page);
-	if (!msr_bitmap_l1) {
-		nested_release_page_clean(page);
-		WARN_ON(1);
-		return false;
-	}
 
 	memset(msr_bitmap_l0, 0xff, PAGE_SIZE);