From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with ESMTP id 0DBA06B00DB for ; Wed, 3 Jun 2009 11:48:34 -0400 (EDT) Date: Wed, 3 Jun 2009 12:21:51 +0200 From: Jens Axboe Subject: Re: [PATCH] [13/16] HWPOISON: The high level memory error handler in the VM v3 Message-ID: <20090603102151.GM11363@kernel.dk> References: <20090528082616.GG6920@wotan.suse.de> <20090528095934.GA10678@localhost> <20090528122357.GM6920@wotan.suse.de> <20090528135428.GB16528@localhost> <20090601115046.GE5018@wotan.suse.de> <20090601140553.GA1979@localhost> <20090601144050.GA12099@wotan.suse.de> <20090602111407.GA17234@localhost> <20090602121940.GD1392@wotan.suse.de> <20090602125134.GA20462@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090602125134.GA20462@localhost> Sender: owner-linux-mm@kvack.org To: Wu Fengguang Cc: Nick Piggin , Andi Kleen , "hugh@veritas.com" , "riel@redhat.com" , "akpm@linux-foundation.org" , "chris.mason@oracle.com" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" List-ID: On Tue, Jun 02 2009, Wu Fengguang wrote: > > And then this is possible because you aren't violating mm > > assumptions due to 1b. This proceeds just as the existing > > pagecache mce error handler case which exists now. > > Yeah that's a good scheme - we are talking about two interception > scheme. Mine is passive one and yours is active one. > > passive: check hwpoison pages at __generic_make_request()/elv_next_request() > (the code will be enabled by an mce_bad_io_pages counter) That's not a feasible approach at all, it'll add O(N) scan of a bio at queue time. Ditto for the elv_next_request() approach. What would be cheaper is to check the pages at dma map time, since you have to scan the request anyway. That means putting it in blk_rq_map_sg() or similar. -- Jens Axboe -- 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