From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wols Lists Subject: Re: [PATCH 2/2] md/raid0: Do not bypass blocking queue entered for raid0 bios Date: Wed, 8 May 2019 10:29:22 +0100 Message-ID: <5CD2A172.4010302@youngman.org.uk> References: <20190430223722.20845-1-gpiccoli@canonical.com> <20190430223722.20845-2-gpiccoli@canonical.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Song Liu , "Guilherme G. Piccoli" Cc: axboe@kernel.dk, linux-raid , Tetsuo Handa , kernel@gpiccoli.net, stable@vger.kernel.org, Ming Lei , linux-block@vger.kernel.org, dm-devel@redhat.com, Jay Vosburgh , Gavin Guo List-Id: linux-raid.ids On 06/05/19 22:07, Song Liu wrote: > Could you please run a quick test with raid5? I am wondering whether > some race condition could get us into similar crash. If we cannot easily > trigger the bug, we can process with this version. Bear in mind I just read the list and write documentation, but ... My gut feeling is that if it can theoretically happen for all raid modes, it should be fixed for all raid modes. What happens if code changes elsewhere and suddenly it really does happen for say raid-5? On the other hand, if fixing it in md.c only gets tested for raid-0, how do we know it will actually work for other raids if they do suddenly start falling through. Academic purity versus engineering practicality :-) Cheers, Wol