From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Ewan D. Milne" Subject: Re: [PATCH 1/3] scsi_dh_rdac: switch to scsi_execute_req_flags() Date: Thu, 03 Nov 2016 12:11:39 -0400 Message-ID: <1478189499.1001.26.camel@localhost.localdomain> References: <1478036978-30583-1-git-send-email-hare@suse.de> <1478036978-30583-2-git-send-email-hare@suse.de> <1478101469.1001.9.camel@localhost.localdomain> <6bb2b352-d137-a9da-2f35-e6b0cdef4774@suse.com> Reply-To: emilne@redhat.com Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from mx1.redhat.com ([209.132.183.28]:41934 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758307AbcKCQLl (ORCPT ); Thu, 3 Nov 2016 12:11:41 -0400 In-Reply-To: <6bb2b352-d137-a9da-2f35-e6b0cdef4774@suse.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Hannes Reinecke Cc: "Martin K. Petersen" , Christoph Hellwig , James Bottomley , linux-scsi@vger.kernel.org On Wed, 2016-11-02 at 22:27 +0100, Hannes Reinecke wrote: > On 11/02/2016 04:44 PM, Ewan D. Milne wrote: > > In this and other places the patch changes the code from submitting the > > INQUIRY/EVPD command for the page it wants, to calling scsi_get_vpd_page(). > > scsi_get_vpd_page() will return -EINVAL if the device did not report in > > VPD page 0 that the requested page is in the list of supported pages. > > Did you actually verify that the RDAC returns all of these VPD pages in > > its VPD page 0 list? > > > > I mean, I know it's supposed to, but these are old devices. > > > Errm. > > Old? Don't tell that to the E-Series folk; you'll never again get > something sponsored :-) > > No, seriously: RDAC mode is continued to be supported even on the latest > models, and all firmware revisions I've got support VPD page 0x0. > And incidentally, this is the very same method we're using for basically > all tools accessing VPD page 0x83, be it in the kernel or something like > sg3_utils. > _Not_ asking for page 0x0 lead to crashes on several older devices. You're right, I was curious, so I resurrected our old RDAC, and it does in fact report the necessary supported VPD pages: # sg_vpd -H /dev/sg4 Supported VPD pages VPD page: 00 20 00 00 12 00 80 83 85 86 87 b0 b1 c0 c1 c2 c3 ............... 10 c4 c8 c9 ca d0 e0 ...... My concern was that older devices might not do this, I think there have been some arrays that had hidden commands/pages. -Ewan