From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with SMTP id 7250E6B01EF for ; Fri, 23 Apr 2010 09:52:27 -0400 (EDT) Message-ID: <4BD1A609.4040401@redhat.com> Date: Fri, 23 Apr 2010 09:52:09 -0400 From: Rik van Riel MIME-Version: 1.0 Subject: Re: [PATCH] [BUGFIX] rmap: remove anon_vma check in page_address_in_vma() References: <20100422054241.GB10957@spritzerA.linux.bs1.fc.nec.co.jp> <4BD0688A.7050806@redhat.com> <20100423020827.GB7383@spritzerA.linux.bs1.fc.nec.co.jp> In-Reply-To: <20100423020827.GB7383@spritzerA.linux.bs1.fc.nec.co.jp> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Naoya Horiguchi Cc: linux-mm , LKML , Andrew Morton , Andi Kleen List-ID: On 04/22/2010 10:08 PM, Naoya Horiguchi wrote: > Currently page_address_in_vma() compares vma->anon_vma and page_anon_vma(page) > for parameter check, but in 2.6.34 a vma can have multiple anon_vmas with > anon_vma_chain, so current check does not work. (For anonymous page shared by > multiple processes, some verified (page,vma) pairs return -EFAULT wrongly.) > > We can go to checking all anon_vmas in the "same_vma" chain, but it needs > to meet lock requirement. Instead, we can remove anon_vma check safely > because page_address_in_vma() assumes that page and vma are already checked > to belong to the identical process. > > Signed-off-by: Naoya Horiguchi > Cc: Andrew Morton > Cc: Rik van Riel > Cc: Andi Kleen Reviewed-by: Rik van Riel -- 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: email@kvack.org