From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lithops.sigma-star.at ([195.201.40.130]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gC8NN-0004nN-5M for linux-um@lists.infradead.org; Mon, 15 Oct 2018 19:18:07 +0000 From: Richard Weinberger Subject: Re: [PATCH, RFC] ubd: remove use of blk_rq_map_sg Date: Mon, 15 Oct 2018 21:17:46 +0200 Message-ID: <20263939.GgfHUqOn1T@blindfold> In-Reply-To: <20181015084541.GA27159@lst.de> References: <20181015065637.1860-1-hch@lst.de> <4055590.4i3nx3fRmo@blindfold> <20181015084541.GA27159@lst.de> MIME-Version: 1.0 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: Christoph Hellwig Cc: axboe@kernel.dk, linux-block@vger.kernel.org, linux-um@lists.infradead.org, anton.ivanov@cambridgegreys.com Am Montag, 15. Oktober 2018, 10:45:41 CEST schrieb Christoph Hellwig: > On Mon, Oct 15, 2018 at 10:40:06AM +0200, Richard Weinberger wrote: > > hm, this breaks UML. > > Every filesystem fails to mount. > > > > I did some very rough tests, it seems that the driver fails to read > > data correctly as soon the upper layer tries to get more than 4096 bytes > > at once out of the block device. > > > > IOW: > > dd if=/dev/ubda bs=4096 count=1 skip=0 2>/dev/null| md5sum - > > is good. > > As soon I set bs to something greater it returns garbage. > > > > Later this day I might have some cycles left to debug further. > > It probably needs this on top: Sadly not. I'm checking now what exactly is broken. BTW: Why are you using for_each_bio() with bio_for_each_segment()? I thought we have rq_for_each_segment() for that. Thanks, //richard _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um