From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Christie Subject: Re: [PATCH] 2.6.25-rc4-git3 - inquiry cmd issued via /dev/sg? device causes infinite loop in 2.6.24 Date: Mon, 17 Mar 2008 13:08:39 -0500 Message-ID: <47DEB3A7.1030600@cs.wisc.edu> References: <47D7035F.5000700@sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from sabe.cs.wisc.edu ([128.105.6.20]:47874 "EHLO sabe.cs.wisc.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750762AbYCQSIx (ORCPT ); Mon, 17 Mar 2008 14:08:53 -0400 In-Reply-To: <47D7035F.5000700@sgi.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Michael Reed Cc: Douglas Gilbert , linux-scsi , Jeremy Higdon , James Bottomley Michael Reed wrote: > - ++blk_size; /* don't know why */ > -/* round request up to next highest SG_SECTOR_SZ byte boundary */ I think we can remove this code. This was asked before, and here is Doug's reply: http://www.mail-archive.com/linux-scsi@vger.kernel.org/msg11757.html It was probaly due to some weirdness in that the scatterlist that sg.c made used to be sent directly to the LLD (now it is only used to hold/organize the pages/segments that the sg and st driver manages in their internal reserves), or maybe it had something to do with that and dma alignment problems or something. I really have no idea, but the block layer SG IO code has not been rounding up in its indirect path and it has been fine.