From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boaz Harrosh Subject: Re: [PATCH] zfcp: Test kmalloc failure in scsi_get_vpd_page() Date: Sun, 08 Nov 2009 11:19:45 +0200 Message-ID: <4AF68D31.4000403@panasas.com> References: <4A92BE18.50208@gmail.com> <1251416731.27356.8.camel@mulgrave.site> <4A9A6676.8050304@panasas.com> <1251642902.10135.4.camel@mulgrave.site> <1257273187.9427.22.camel@mulgrave.site> <4AF14147.4050102@panasas.com> <1257347360.2697.20.camel@mulgrave.site> <4AF1A941.3080808@panasas.com> <1257357013.10416.8.camel@mulgrave.site> <4AF28CCF.8020605@panasas.com> <1257450093.10355.28.camel@mulgrave.site> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: Received: from dip-colo-pa.panasas.com ([67.152.220.67]:54142 "EHLO daytona.int.panasas.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753318AbZKHJTn (ORCPT ); Sun, 8 Nov 2009 04:19:43 -0500 In-Reply-To: <1257450093.10355.28.camel@mulgrave.site> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: James Bottomley Cc: Roel Kluin , linux-scsi@vger.kernel.org, Andrew Morton , "Martin K. Petersen" On 11/05/2009 09:41 PM, James Bottomley wrote: > On Thu, 2009-11-05 at 10:29 +0200, Boaz Harrosh wrote: >> On 11/04/2009 07:50 PM, James Bottomley wrote: >>> On Wed, 2009-11-04 at 18:18 +0200, Boaz Harrosh wrote: >>> >>> The point of checking is not to send a VPD inquiry to USB devices that >>> don't support it. These have a very limited range of supported VPD >>> pages. >>> >> >> OK thanks. But maybe just define a MIN_INQUIRY_SIZE instead of hard >> coded 32 everywhere, and use that. So in future if such a device is >> found we can easily change it. > > So the minimum inquiry size would actually be 36 ... from > scsi_scan.c ... and that's hard coded to a value too. > two wrongs don't make a right ;-) But yes, sorry, that's a wrong name. I meant minimum-vpd-page-inquiry, a specifc constant for that function we are talking about. >> (Never say never ;-)) > > I'm hoping that by the time USB devices get complex enough to need more > than 28 VPD pages, they've actually discovered what conforming to the > standards means. > I don't understand what your saying. I'm making a simple and sane point. A new comer, from looking at the API, will say "Haa I only need 12 bytes lets set that". But no the buffer has dual purpose, one get the page I want, but zero check these crap USB devices. (And all those other subtle things) So you are actually going to argue that a patch should introduce an hard coded 32 unexplained, and refuse a constant that actually communicates the issue, which also covers our asses from the hopes we make. Because I sure hope so too, but I'm also 48 years old. > James > > Boaz