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[209.85.220.65]) by mx.google.com with SMTPS id u3sor5791775ljg.35.2019.06.01.03.41.11 for (Google Transport Security); Sat, 01 Jun 2019 03:41:11 -0700 (PDT) Received-SPF: pass (google.com: domain of miguel.ojeda.sandonis@gmail.com designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=rjoKGRLL; spf=pass (google.com: domain of miguel.ojeda.sandonis@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=miguel.ojeda.sandonis@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=HfG8SFYlwhX2T6RV6yxB9+NDJcpkM3O1MaSrYiv8LPo=; b=rjoKGRLLtJKt2NLllelbm573MDL2ykr+faYahdLKjSY7Y5bcl9oOcfgIPjxjLRT8Rg mveZbNR6/4PcibX5IGuiP2ht/kulnh3WcI4MaWK2Y1A0DXjutsYEwD3qTftFhiv8GqfK 7+qaDof1ZYd3doX7X1h+7WeRcfHVpsj0pwMdcoQ9xEdSqbExbR0q5XsGZkhOjNfO0bju T5gSSanCNIC12PTxtOjXIjZmgaW8TSijlkhgbcIQjczBFFhQDLrsYZl8VwB/3MG1Gh3c 8YfiZYGEuJBRTypFu7XSl1WsefQ2ppNKSDi5woINqma62CXA6zpRINHHLvZ5yGrTw5X8 DUHQ== X-Google-Smtp-Source: APXvYqwo+hRPRQiNwv/GCJLziYFhPRmDBka35PISCOCnRhr43lAq1JZzc9/8GlGwArLsGmyrafsMQ15XfcxCKdwIxNE= X-Received: by 2002:a2e:9157:: with SMTP id q23mr8892650ljg.188.1559385671552; Sat, 01 Jun 2019 03:41:11 -0700 (PDT) MIME-Version: 1.0 References: <20190528193004.GA7744@gmail.com> In-Reply-To: From: Miguel Ojeda Date: Sat, 1 Jun 2019 12:41:00 +0200 Message-ID: Subject: Re: [PATCH] mm: Fail when offset == num in first check of vm_map_pages_zero() To: Souptick Joarder , Andrew Morton Cc: Matthew Wilcox , Peter Zijlstra , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , "Aneesh Kumar K.V" , Huang Ying , open list , Linux-MM Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, May 29, 2019 at 9:09 AM Souptick Joarder wrote: > > On Wed, May 29, 2019 at 1:38 AM Miguel Ojeda > wrote: > > > > If the user asks us for offset == num, we should already fail in the > > first check, i.e. the one testing for offsets beyond the object. > > > > At the moment, we are failing on the second test anyway, > > since count cannot be 0. Still, to agree with the comment of the first > > test, we should first there. > > I think, we need to cc linux-mm. Cc'ing Andrew as well as Souptick suggested me. Cheers, Miguel