From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: [PATCH 2/6] scsi tgt: kill length alignment test in bin_map_user Date: Thu, 16 Feb 2006 21:00:10 +0100 Message-ID: <20060216200010.GZ4203@suse.de> References: <1140119617.20193.49.camel@max> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from ns.virtualhost.dk ([195.184.98.160]:284 "EHLO virtualhost.dk") by vger.kernel.org with ESMTP id S964890AbWBPUAL (ORCPT ); Thu, 16 Feb 2006 15:00:11 -0500 Content-Disposition: inline In-Reply-To: <1140119617.20193.49.camel@max> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Mike Christie Cc: linux-scsi@vger.kernel.org On Thu, Feb 16 2006, Mike Christie wrote: > Subject: [PATCH] block layer: kill length alignment test in bin_map_user > > The tgt project is mapping in bios using bio_map_user. The current targets > do not need their len to be aligned with a queue limit so this check is > causing some problems. Note: pointers passed into the kernel are properly > aligned by usersapace tgt code so the uaddr check in bio_map_user is ok. > > > The major user, blk_bio_map_user checks for the len before mapping > so it is not affected by this patch. > > And the semi-newly added user blk_rq_map_user_iov has been failing > out when the len is not aligned properly so maybe people have been > good and not sending misaligned lens or that path is not used very > often and this change will not be very dangerous. st and sg do not > check the length and we have not seen any problem reports from those > wider used paths so this patch should be fairly safe - for mm > and wider testing at least. As previously discussed, this is fine with me. It's a mixed check anyways, if we need length check in the future it should be a seperate attribute. -- Jens Axboe