From 29ecd66019047768080e8eeab4cd6582b28383a2 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Sun, 6 Sep 2015 16:24:50 +0200 Subject: [PATCH] KVM: x86: avoid uninitialized variable warning This does not show up on all compiler versions, so it sneaked into the first 4.3 pull request. The fix is to mimic the logic of the "print sptes" loop in the "fill array" loop. Then leaf and root can be both initialized unconditionally. Note that "leaf" now points to the first unused element of the array, not the last filled element. Reported-by: Linus Torvalds Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index fb16a8e..69088a1 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -3309,13 +3309,14 @@ walk_shadow_page_get_mmio_spte(struct kvm_vcpu *vcpu, u64 addr, u64 *sptep) walk_shadow_page_lockless_begin(vcpu); - for (shadow_walk_init(&iterator, vcpu, addr), root = iterator.level; + for (shadow_walk_init(&iterator, vcpu, addr), + leaf = root = iterator.level; shadow_walk_okay(&iterator); __shadow_walk_next(&iterator, spte)) { - leaf = iterator.level; spte = mmu_spte_get_lockless(iterator.sptep); sptes[leaf - 1] = spte; + leaf--; if (!is_shadow_present_pte(spte)) break; @@ -3329,7 +3330,7 @@ walk_shadow_page_get_mmio_spte(struct kvm_vcpu *vcpu, u64 addr, u64 *sptep) if (reserved) { pr_err("%s: detect reserved bits on spte, addr 0x%llx, dump hierarchy:\n", __func__, addr); - while (root >= leaf) { + while (root > leaf) { pr_err("------ spte 0x%llx level %d.\n", sptes[root - 1], root); root--; -- 2.7.4