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[209.132.180.67]) by mx.google.com with ESMTP id p84-v6si34516393pfa.180.2018.05.30.05.15.47; Wed, 30 May 2018 05:16:01 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@linaro.org header.s=google header.b=QseURNvg; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752963AbeE3MON (ORCPT + 99 others); Wed, 30 May 2018 08:14:13 -0400 Received: from mail-oi0-f66.google.com ([209.85.218.66]:42360 "EHLO mail-oi0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752773AbeE3MOL (ORCPT ); Wed, 30 May 2018 08:14:11 -0400 Received: by mail-oi0-f66.google.com with SMTP id t27-v6so16092770oij.9 for ; Wed, 30 May 2018 05:14:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=+gfSbYOueV2f7nJa0daAj0q4HUXatj+023JbOyAWhHY=; b=QseURNvga+FIOr0UmAWCMEfdZru9uleuv/6cD6xKJTcxC1gklIJzVuM01N6qaUkxk9 B9AFoYuou5tE0dltD3H7HKsuiqwndLk3ic3ksMRi/RbE+zq21NwngsmkKCom7+VowMjT hpO4+wVkeo5SZ2W1PZg22AfH2A+/qgASAdLL4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=+gfSbYOueV2f7nJa0daAj0q4HUXatj+023JbOyAWhHY=; b=N5xsshBHdCpveMKorGZCAXbmnEY+vLyOvZpO5gvkt0cAQXTvY0bE+6AueEAOKlfVCj 8u4JD87EjP2IdapFHBsQDMI9Hs9LS7ifu9qNnSSq+0Td4B4yVb5r6cg4nqTMOfeGF/5P wcj+vSoLpin9BlgAZ6nCLZpgyBdyoh/twSnOh+5kUZcimvyhQspvBEjc4M9MMNAWZe8L TNTlCAhDaSiZ/hS9IaYxk8oZeBp9bM0VvRNUCJApbjOTn9qLXdEi60STQI07zrUKjvmZ CVqAfPQ/lDZXZVrxcL6I9iXDoE3697kX8GH4vop8uMCL34af9ii7oJdwwOGCdf52ACru IZjQ== X-Gm-Message-State: ALKqPwfSY6GeGb2v6XhLa9iXqMUVoHXUrUDoDz60Bdmh2RkXdWM2CQ40 guBzig3w1MKREaMJtdqdJnVTkJtuwA6LMEDbnS10qIwLWxU= X-Received: by 2002:aca:acd7:: with SMTP id v206-v6mr1365879oie.320.1527682450429; Wed, 30 May 2018 05:14:10 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:a9d:2d44:0:0:0:0:0 with HTTP; Wed, 30 May 2018 05:14:09 -0700 (PDT) In-Reply-To: <20180530120133.GC17450@bombadil.infradead.org> References: <59623b15001e5a20ac32b1a393db88722be2e718.1527679621.git.baolin.wang@linaro.org> <20180530120133.GC17450@bombadil.infradead.org> From: Baolin Wang Date: Wed, 30 May 2018 20:14:09 +0800 Message-ID: Subject: Re: [PATCH] mm: dmapool: Check the dma pool name To: Matthew Wilcox Cc: linux-mm@kvack.org, LKML , Arnd Bergmann , Mark Brown Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 30 May 2018 at 20:01, Matthew Wilcox wrote: > On Wed, May 30, 2018 at 07:28:43PM +0800, Baolin Wang wrote: >> It will be crash if we pass one NULL name when creating one dma pool, >> so we should check the passing name when copy it to dma pool. > > NAK. Crashing is the appropriate thing to do. Fix the caller to not > pass NULL. > > If you permit NULL to be passed then you're inviting crashes or just > bad reporting later when pool->name is printed. I think it just prints one NULL pool name. Sometimes the device doesn't care the dma pool names, so I think we can make code more solid to valid the passing parameters like other code does. Or can we add check to return NULL when the passing name is NULL instead of crashing the kernel? Thanks. -- Baolin.wang Best Regards