From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: Re: [PATCH] KVM: Fix warning in emulator_cmpxchg_emulated Date: Thu, 08 Dec 2011 10:25:24 +0200 Message-ID: <1323332724.3904.7.camel@lappy> References: <1323325040-10548-1-git-send-email-levinsasha928@gmail.com> <4EE06F78.6030305@web.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org, avi@redhat.com, mtosatti@redhat.com To: Jan Kiszka Return-path: Received: from mail-bw0-f46.google.com ([209.85.214.46]:63996 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752308Ab1LHIZq (ORCPT ); Thu, 8 Dec 2011 03:25:46 -0500 Received: by bkbzv3 with SMTP id zv3so1312249bkb.19 for ; Thu, 08 Dec 2011 00:25:44 -0800 (PST) In-Reply-To: <4EE06F78.6030305@web.de> Sender: kvm-owner@vger.kernel.org List-ID: On Thu, 2011-12-08 at 09:04 +0100, Jan Kiszka wrote: > On 2011-12-08 07:17, Sasha Levin wrote: > > Make sure 'exchanged' is initialized. Fixes the following warning: > > > > arch/x86/kvm/x86.c: In function 'emulator_cmpxchg_emulated': > > arch/x86/kvm/x86.c:3794:7: warning: 'exchanged' may be used uninitialized in this function > > > > Signed-off-by: Sasha Levin > > --- > > arch/x86/kvm/x86.c | 2 +- > > 1 files changed, 1 insertions(+), 1 deletions(-) > > > > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > > index eeeaf2e..9338afc 100644 > > --- a/arch/x86/kvm/x86.c > > +++ b/arch/x86/kvm/x86.c > > @@ -3791,7 +3791,7 @@ static int emulator_cmpxchg_emulated(struct x86_emulate_ctxt *ctxt, > > gpa_t gpa; > > struct page *page; > > char *kaddr; > > - bool exchanged; > > + bool exchanged = false; > > > > /* guests cmpxchg8b have to be emulated atomically */ > > if (bytes > 8 || (bytes & (bytes - 1))) > > Isn't BUG() tagged as no-return in the kernel? Because this > initialization is obviously unneeded. It looks like __builtin_unreachable() requires a gcc newer than mine. -- Sasha.