From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [PATCH] kvm: coalesced_mmio: remove one redundant check inside of coalesced_mmio_in_range() Date: Thu, 11 Dec 2014 12:29:01 +0100 Message-ID: <54897FFD.5030806@redhat.com> References: <1418266961-27277-1-git-send-email-tiejun.chen@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org To: Tiejun Chen Return-path: Received: from mx1.redhat.com ([209.132.183.28]:43259 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750702AbaLKLqQ (ORCPT ); Thu, 11 Dec 2014 06:46:16 -0500 In-Reply-To: <1418266961-27277-1-git-send-email-tiejun.chen@intel.com> Sender: kvm-owner@vger.kernel.org List-ID: On 11/12/2014 04:02, Tiejun Chen wrote: > We already check 'len' above to make sure it already isn't > negative here, so indeed, (addr + len < addr) should never be happened. ... except if there is an overflow. Paolo > Signed-off-by: Tiejun Chen > --- > virt/kvm/coalesced_mmio.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/virt/kvm/coalesced_mmio.c b/virt/kvm/coalesced_mmio.c > index 00d8642..60f59cd 100644 > --- a/virt/kvm/coalesced_mmio.c > +++ b/virt/kvm/coalesced_mmio.c > @@ -30,8 +30,6 @@ static int coalesced_mmio_in_range(struct kvm_coalesced_mmio_dev *dev, > */ > if (len < 0) > return 0; > - if (addr + len < addr) > - return 0; > if (addr < dev->zone.addr) > return 0; > if (addr + len > dev->zone.addr + dev->zone.size) >