From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759605Ab2EKMx1 (ORCPT ); Fri, 11 May 2012 08:53:27 -0400 Received: from mga01.intel.com ([192.55.52.88]:56395 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755869Ab2EKMxZ (ORCPT ); Fri, 11 May 2012 08:53:25 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.71,315,1320652800"; d="scan'208";a="164938898" Message-ID: <4FAD0BB9.3070206@intel.com> Date: Fri, 11 May 2012 20:53:13 +0800 From: Alex Shi User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:9.0) Gecko/20111229 Thunderbird/9.0 MIME-Version: 1.0 To: Borislav Petkov CC: rob@landley.net, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, arnd@arndb.de, rostedt@goodmis.org, fweisbec@gmail.com, jeremy@goop.org, gregkh@linuxfoundation.org, riel@redhat.com, luto@mit.edu, avi@redhat.com, len.brown@intel.com, dhowells@redhat.com, fenghua.yu@intel.com, ak@linux.intel.com, cpw@sgi.com, steiner@sgi.com, akpm@linux-foundation.org, penberg@kernel.org, hughd@google.com, rientjes@google.com, kosaki.motohiro@jp.fujitsu.com, n-horiguchi@ah.jp.nec.com, paul.gortmaker@windriver.com, trenn@suse.de, tj@kernel.org, oleg@redhat.com, axboe@kernel.dk, a.p.zijlstra@chello.nl, kamezawa.hiroyu@jp.fujitsu.com, viro@zeniv.linux.org.uk, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 7/7] x86/tlb: add tlb_flushall_factor into sysfs for user testing/tuning References: <1336626013-28413-1-git-send-email-alex.shi@intel.com> <1336626013-28413-8-git-send-email-alex.shi@intel.com> <20120510082731.GC30055@aftab.osrc.amd.com> <4FAC62B9.9090304@intel.com> <20120511095136.GE8913@aftab.osrc.amd.com> In-Reply-To: <20120511095136.GE8913@aftab.osrc.amd.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/11/2012 05:51 PM, Borislav Petkov wrote: > On Fri, May 11, 2012 at 08:52:09AM +0800, Alex Shi wrote: >>>> +#ifdef CONFIG_DEBUG_TLBFLUSH >> >>>> +static ssize_t __tlb_flushall_factor_store(const char *buf, >>>> + size_t count, int smt) >>>> +{ >>>> + short factor = 0; >>>> + >>>> + if (sscanf(buf, "%hd", &factor) != 1) >>>> + return -EINVAL; >>> >>> This means only single-digit factors, right? >> >> No, you can try '32' '16' etc. not a 'single-digit'. > > Ah, misread sscanf, nevermind. > >>> Why not use kstrtoul? >> >> any advantage of this? > > Well, sscanf uses simple_strto* and those miss overflow checks etc, see > 33ee3b2e2eb9b4b6c64dcf9ed66e2ac3124e748c for details. Thanks for reminder! > > Btw, there are other kstrto* functions which you could use to fit better > the argument type and size passed to tlb_flushall_factor. > >