From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 13 May 2003 18:10:22 -0700 From: Andrew Morton Subject: Re: Race between vmtruncate and mapped areas? Message-Id: <20030513181022.6dbc5418.akpm@digeo.com> In-Reply-To: <220550000.1052866808@baldur.austin.ibm.com> References: <154080000.1052858685@baldur.austin.ibm.com> <3EC15C6D.1040403@kolumbus.fi> <199610000.1052864784@baldur.austin.ibm.com> <20030513224929.GX8978@holomorphy.com> <220550000.1052866808@baldur.austin.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Dave McCracken Cc: wli@holomorphy.com, mika.penttila@kolumbus.fi, linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: Dave McCracken wrote: > > Actually it does fix it. I added code in vmtruncate_list() to do a > down_write(&vma->vm_mm->mmap_sem) around the zap_page_range(), and the > problem went away. It serializes against any outstanding page faults on a > particular page table. New faults will see that the page is no longer in > the file and fail with SIGBUS. Andrew's test case stopped failing. > > I've attached the patch so you can see what I did. > > Can anyone think of any gotchas to this solution? mmap_sem nests outside i_shared_sem. -- 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/ . Don't email: aart@kvack.org