linux-kernel - [RFC PATCH 16/16] KVM: arm64: Don't bother nullifying "vma" in mem abort path

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Message-ID: <20250821210042.3451147-17-seanjc@google.com>
Date: Thu, 21 Aug 2025 14:00:42 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Marc Zyngier <maz@...nel.org>, Oliver Upton <oliver.upton@...ux.dev>
Cc: linux-arm-kernel@...ts.infradead.org, kvmarm@...ts.linux.dev, 
	linux-kernel@...r.kernel.org, Sean Christopherson <seanjc@...gle.com>, 
	James Houghton <jthoughton@...gle.com>
Subject: [RFC PATCH 16/16] KVM: arm64: Don't bother nullifying "vma" in mem
 abort path

Now that the local "vma" in kvm_gather_fault_vma_info() will naturally go
out of scope when mmap_lock is dropped, don't bother nullifying the
variable.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/arm64/kvm/mmu.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index ea326d66f027..435582e997ce 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -1559,9 +1559,6 @@ static int kvm_gather_fault_vma_info(struct kvm_vcpu *vcpu,
 	fault->vma.vm_flags = vma->vm_flags;
 	fault->vma.is_cacheable = kvm_vma_is_cacheable(vma);
 
-	/* Don't use the VMA after the unlock -- it may have vanished */
-	vma = NULL;
-
 	/*
 	 * Read mmu_invalidate_seq so that KVM can detect if the results of
 	 * vma_lookup() or __kvm_faultin_pfn() become stale prior to
-- 
2.51.0.261.g7ce5a0a67e-goog