From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f49.google.com (mail-pa0-f49.google.com [209.85.220.49]) by kanga.kvack.org (Postfix) with ESMTP id C11DB6B0036 for ; Wed, 30 Jul 2014 06:52:54 -0400 (EDT) Received: by mail-pa0-f49.google.com with SMTP id hz1so1312688pad.36 for ; Wed, 30 Jul 2014 03:52:54 -0700 (PDT) Received: from g4t3426.houston.hp.com (g4t3426.houston.hp.com. [15.201.208.54]) by mx.google.com with ESMTPS id ik3si1940367pbc.249.2014.07.30.03.52.53 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Wed, 30 Jul 2014 03:52:53 -0700 (PDT) Message-ID: <1406717571.9336.19.camel@buesod1.americas.hpqcorp.net> Subject: Re: [PATCH] mm: BUG when __kmap_atomic_idx crosses boundary From: Davidlohr Bueso Date: Wed, 30 Jul 2014 03:52:51 -0700 In-Reply-To: <1406716641.9336.17.camel@buesod1.americas.hpqcorp.net> References: <1406710355-4360-1-git-send-email-cpandya@codeaurora.org> <20140730020615.2f943cf7.akpm@linux-foundation.org> <1406716641.9336.17.camel@buesod1.americas.hpqcorp.net> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Chintan Pandya , linux-kernel@vger.kernel.org, linux-mm@kvack.org On Wed, 2014-07-30 at 03:37 -0700, Davidlohr Bueso wrote: > On Wed, 2014-07-30 at 02:06 -0700, Andrew Morton wrote: > > On Wed, 30 Jul 2014 14:22:35 +0530 Chintan Pandya wrote: > > > > > __kmap_atomic_idx >= KM_TYPE_NR or < ZERO is a bug. > > > Report it even if CONFIG_DEBUG_HIGHMEM is not enabled. > > > That saves much debugging efforts. > > > > Please take considerably more care when preparing patch changelogs. > > > > kmap_atomic() is a very commonly called function so we'll need much > > more detail than this to justify adding overhead to it. > > > > I don't think CONFIG_DEBUG_HIGHMEM really needs to exist. We could do > > s/CONFIG_DEBUG_HIGHMEM/CONFIG_DEBUG_VM/g and perhaps your secret bug > > whatever it was would have been found more easily. > > Agreed, it would be nice to fold DEBUG_HIGHMEM into DEBUG_VM. However > you'd still need some kind of intermediate option as DEBUG_VM must still > exist if !HIGHMEM. Actually no, it's a lot more straightforward than I thought. -- 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