From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io1-xd31.google.com ([2607:f8b0:4864:20::d31]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gMHcK-0006dl-Vp for linux-um@lists.infradead.org; Mon, 12 Nov 2018 19:11:26 +0000 Received: by mail-io1-xd31.google.com with SMTP id b26-v6so6354781ioc.6 for ; Mon, 12 Nov 2018 11:11:11 -0800 (PST) Subject: Re: New Patch series for the UBD Driver References: <20181112174201.12290-1-anton.ivanov@cambridgegreys.com> <62f14981-9804-8fac-c3ec-b544a90751c3@kernel.dk> <58614d39-8c3b-4e8e-7b41-633bb52b533e@cambridgegreys.com> <880075e6-1032-fe4f-0001-085d7409eb54@kernel.dk> <2b318d17-7fde-991b-fda4-271fde2a7db9@kernel.dk> <0e31d0a6-64f0-208e-bfc8-acd05db432f1@cambridgegreys.com> <1d334c50-0f89-70e7-b6c7-fe0d719ed5df@cambridgegreys.com> From: Jens Axboe Message-ID: <1e27868d-974b-9554-1010-a7e28a238479@kernel.dk> Date: Mon, 12 Nov 2018 12:11:08 -0700 MIME-Version: 1.0 In-Reply-To: <1d334c50-0f89-70e7-b6c7-fe0d719ed5df@cambridgegreys.com> Content-Language: en-US List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-um" Errors-To: linux-um-bounces+geert=linux-m68k.org@lists.infradead.org To: Anton Ivanov , linux-um@lists.infradead.org Cc: richard@nod.at, hch@lst.de On 11/12/18 11:41 AM, Anton Ivanov wrote: >>> And hang. Let me try a few more times to see if I can get the spinlock >>> recursion and/or abort instead of hang case (they are more difficult to >>> reproduce). >> This shows exactly what I was talking about, you are trying to >> issue IO from irq/non-blocking context. If you look up the warning, >> that's exactly what it is telling you. > > > So why does this happen only in the case of an error? Why nothing is > triggered in the OK path? > > After adding this flag I no longer get the block/blk.h:439 The spinlock > recursion and the other barfs are alive and well. > > Back to "what is that" - can I execute blk_update_request, > __blk_mq_end_request, blk_mq_end_request out of an interrupt context? > > It seems that I can when error is BLK_STS_OK, but not when it is not. Post a new stack trace with BLOCKING set. Of course you can call the end request functions from irq context, most drivers end up doing that. For OK and error. There's something fundamentally wrong with your case, it might be reuse or something like that. -- Jens Axboe _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um