From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx126.postini.com [74.125.245.126]) by kanga.kvack.org (Postfix) with SMTP id 695836B0069 for ; Thu, 31 May 2012 02:50:21 -0400 (EDT) Received: by dakp5 with SMTP id p5so1043206dak.14 for ; Wed, 30 May 2012 23:50:20 -0700 (PDT) Date: Wed, 30 May 2012 23:50:18 -0700 (PDT) From: David Rientjes Subject: Re: [PATCH -V7 02/14] hugetlbfs: don't use ERR_PTR with VM_FAULT* values In-Reply-To: <20120531054533.GE24855@skywalker.linux.vnet.ibm.com> Message-ID: References: <1338388739-22919-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1338388739-22919-3-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <20120531054533.GE24855@skywalker.linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: "Aneesh Kumar K.V" Cc: linux-mm@kvack.org, kamezawa.hiroyu@jp.fujitsu.com, dhillf@gmail.com, mhocko@suse.cz, akpm@linux-foundation.org, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, Andrea Arcangeli On Thu, 31 May 2012, Aneesh Kumar K.V wrote: > > Yeah, but is there a reason for using VM_FAULT_HWPOISON_LARGE_MASK since > > that's the only VM_FAULT_* value that is greater than MAX_ERRNO? The rest > > of your patch set doesn't require this, so I think this change should just > > be dropped. (And PTR_ERR() still returns long, this wasn't fixed from my > > original review.) > > > > The changes was done as per Andrew's request so that we don't have such hidden > dependencies on the values of VM_FAULT_*. Yes it can be a seperate patch from > the patchset. I have changed int to long as per your review. > I think it confuscates the code, can't we just add something like BUILD_BUG_ON() to ensure that PTR_ERR() never uses values that are outside the bounds of MAX_ERRNO so we'll catch these at compile time if mm/hugetlb.c or anything else is ever extended to use such values? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org