From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f176.google.com (mail-wi0-f176.google.com [209.85.212.176]) by kanga.kvack.org (Postfix) with ESMTP id 79F6B6B0253 for ; Mon, 9 Nov 2015 03:16:53 -0500 (EST) Received: by wikq8 with SMTP id q8so62938066wik.1 for ; Mon, 09 Nov 2015 00:16:53 -0800 (PST) Received: from mail-wi0-f172.google.com (mail-wi0-f172.google.com. [209.85.212.172]) by mx.google.com with ESMTPS id s7si15284035wmd.28.2015.11.09.00.16.52 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 09 Nov 2015 00:16:52 -0800 (PST) Received: by wiby19 with SMTP id y19so10833799wib.0 for ; Mon, 09 Nov 2015 00:16:52 -0800 (PST) Date: Mon, 9 Nov 2015 09:16:50 +0100 From: Michal Hocko Subject: Re: [PATCH] jbd2: get rid of superfluous __GFP_REPEAT Message-ID: <20151109081650.GA8916@dhcp22.suse.cz> References: <1446740160-29094-4-git-send-email-mhocko@kernel.org> <1446826623-23959-1-git-send-email-mhocko@kernel.org> <563D526F.6030504@I-love.SAKURA.ne.jp> <20151108050802.GB3880@thunk.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151108050802.GB3880@thunk.org> Sender: owner-linux-mm@kvack.org List-ID: To: Theodore Ts'o Cc: Tetsuo Handa , linux-mm@kvack.org, Andrew Morton , LKML , john.johansen@canonical.com On Sun 08-11-15 00:08:02, Theodore Ts'o wrote: > On Sat, Nov 07, 2015 at 10:22:55AM +0900, Tetsuo Handa wrote: > > All jbd2_alloc() callers seem to pass GFP_NOFS. Therefore, use of > > vmalloc() which implicitly passes GFP_KERNEL | __GFP_HIGHMEM can cause > > deadlock, can't it? This vmalloc(size) call needs to be replaced with > > __vmalloc(size, flags). > > jbd2_alloc is only passed in the bh->b_size, which can't be > > PAGE_SIZE, so the code path that calls vmalloc() should never get > called. When we conveted jbd2_alloc() to suppor sub-page size > allocations in commit d2eecb039368, there was an assumption that it > could be called with a size greater than PAGE_SIZE, but that's > certaily not true today. Thanks for the clarification. Then the patch can be simplified even more then. ---