From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx203.postini.com [74.125.245.203]) by kanga.kvack.org (Postfix) with SMTP id 7026E6B0044 for ; Mon, 21 May 2012 14:23:56 -0400 (EDT) Message-ID: <4FBA8829.3010800@jp.fujitsu.com> Date: Mon, 21 May 2012 14:23:37 -0400 From: KOSAKI Motohiro MIME-Version: 1.0 Subject: Re: [RFC][PATCH] hugetlb: fix resv_map leak in error path References: <20120518184630.FF3307BD@kernel> In-Reply-To: <20120518184630.FF3307BD@kernel> Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: dave@linux.vnet.ibm.com Cc: cl@linux.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, aarcange@redhat.com, kosaki.motohiro@jp.fujitsu.com, hughd@google.com, rientjes@google.com, adobriyan@gmail.com, akpm@linux-foundation.org, mel@csn.ul.ie On 5/18/2012 2:46 PM, Dave Hansen wrote: > When called for anonymous (non-shared) mappings, > hugetlb_reserve_pages() does a resv_map_alloc(). It depends on > code in hugetlbfs's vm_ops->close() to release that allocation. > > However, in the mmap() failure path, we do a plain unmap_region() > without the remove_vma() which actually calls vm_ops->close(). > > This is a decent fix. This leak could get reintroduced if > new code (say, after hugetlb_reserve_pages() in > hugetlbfs_file_mmap()) decides to return an error. But, I think > it would have to unroll the reservation anyway. > > This hasn't been extensively tested. Pretty much compile and > boot tested along with Christoph's test case. > > Comments? > > > Signed-off-by: Dave Hansen > --- I don't think this is cleaner fix. but I also think we should fix the leak asap. so Let's simple fix first. Acked-by: KOSAKI Motohiro -- 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