From patchwork Tue Mar 4 02:27:17 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 3758381 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 924FABF13A for ; Tue, 4 Mar 2014 02:39:16 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id B1973203EB for ; Tue, 4 Mar 2014 02:39:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D7906203EC for ; Tue, 4 Mar 2014 02:39:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755705AbaCDCjI (ORCPT ); Mon, 3 Mar 2014 21:39:08 -0500 Received: from inca-roads.misterjones.org ([213.251.177.50]:34948 "EHLO inca-roads.misterjones.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755204AbaCDCjH (ORCPT ); Mon, 3 Mar 2014 21:39:07 -0500 Received: from z88l218.static.ctm.net ([202.175.88.218] helo=sofa.wild-wind.fr.eu.org) by cheepnis.misterjones.org with esmtpsa (TLS1.2:RSA_AES_128_CBC_SHA256:128) (Exim 4.80) (envelope-from ) id 1WKf6T-0004uW-N6; Tue, 04 Mar 2014 03:29:10 +0100 From: Marc Zyngier To: Gleb Natapov , Paolo Bonzini Cc: kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, Catalin Marinas , Christoffer Dall Subject: [PATCH 12/12] ARM: KVM: fix warning in mmu.c Date: Tue, 4 Mar 2014 02:27:17 +0000 Message-Id: <1393900037-9369-13-git-send-email-marc.zyngier@arm.com> X-Mailer: git-send-email 1.9.0 In-Reply-To: <1393900037-9369-1-git-send-email-marc.zyngier@arm.com> References: <1393900037-9369-1-git-send-email-marc.zyngier@arm.com> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 202.175.88.218 X-SA-Exim-Rcpt-To: gleb@redhat.com, pbonzini@redhat.com, kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, catalin.marinas@arm.com, christoffer.dall@linaro.org X-SA-Exim-Mail-From: marc.zyngier@arm.com X-SA-Exim-Scanned: No (on cheepnis.misterjones.org); SAEximRunCond expanded to false Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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 d7e998c..80bb1e6 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)) {