From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yk0-f177.google.com (mail-yk0-f177.google.com [209.85.160.177]) by kanga.kvack.org (Postfix) with ESMTP id 4BEEE6B0253 for ; Sun, 8 Nov 2015 00:08:09 -0500 (EST) Received: by ykdv3 with SMTP id v3so133993356ykd.0 for ; Sat, 07 Nov 2015 21:08:09 -0800 (PST) Received: from imap.thunk.org (imap.thunk.org. [2600:3c02::f03c:91ff:fe96:be03]) by mx.google.com with ESMTPS id w144si3798122ywd.67.2015.11.07.21.08.08 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 07 Nov 2015 21:08:08 -0800 (PST) Date: Sun, 8 Nov 2015 00:08:02 -0500 From: Theodore Ts'o Subject: Re: [PATCH] jbd2: get rid of superfluous __GFP_REPEAT Message-ID: <20151108050802.GB3880@thunk.org> 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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <563D526F.6030504@I-love.SAKURA.ne.jp> Sender: owner-linux-mm@kvack.org List-ID: To: Tetsuo Handa Cc: mhocko@kernel.org, linux-mm@kvack.org, Andrew Morton , LKML , Michal Hocko , john.johansen@canonical.com 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. - Ted -- 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