From 56041bf920d2937b7cadcb30cb206f0372eee814 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Thu, 30 Jan 2014 17:38:33 +0000 Subject: [PATCH] ARM: KVM: fix warning in mmu.c MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Compiling with THP enabled leads to the following warning: arch/arm/kvm/mmu.c: In function ‘unmap_range’: arch/arm/kvm/mmu.c:177:39: warning: ‘pte’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (kvm_pmd_huge(*pmd) || page_empty(pte)) { ^ Code inspection reveals that these two cases are mutually exclusive, so GCC is a bit overzealous here. Silence it anyway by initializing pte to NULL and testing it later on. Signed-off-by: Marc Zyngier Acked-by: Christoffer Dall --- arch/arm/kvm/mmu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index d7e998c6a08f..80bb1e6c2c29 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -144,6 +144,7 @@ static void unmap_range(struct kvm *kvm, pgd_t *pgdp, while (addr < end) { pgd = pgdp + pgd_index(addr); pud = pud_offset(pgd, addr); + pte = NULL; if (pud_none(*pud)) { addr = kvm_pud_addr_end(addr, end); continue; @@ -174,7 +175,7 @@ static void unmap_range(struct kvm *kvm, pgd_t *pgdp, /* * If the pmd entry is to be cleared, walk back up the ladder */ - if (kvm_pmd_huge(*pmd) || page_empty(pte)) { + if (kvm_pmd_huge(*pmd) || (pte && page_empty(pte))) { clear_pmd_entry(kvm, pmd, addr); next = kvm_pmd_addr_end(addr, end); if (page_empty(pmd) && !page_empty(pud)) { -- 2.30.2