From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: Re: [PATCH v2] scsi: introduce short_inquiry flag for broken host adapters Date: Tue, 15 Sep 2015 11:24:05 -0700 Message-ID: <1442341445.2177.9.camel@HansenPartnership.com> References: <1441296673-14315-1-git-send-email-vkuznets@redhat.com> <87k2rryczs.fsf@vitty.brq.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from bedivere.hansenpartnership.com ([66.63.167.143]:55599 "EHLO bedivere.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751601AbbIOSYH (ORCPT ); Tue, 15 Sep 2015 14:24:07 -0400 In-Reply-To: <87k2rryczs.fsf@vitty.brq.redhat.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Vitaly Kuznetsov Cc: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, "K. Y. Srinivasan" , Long Li , Dexuan Cui On Tue, 2015-09-15 at 16:27 +0200, Vitaly Kuznetsov wrote: > Vitaly Kuznetsov writes: > > > Some host adapters (e.g. Hyper-V storvsc) are known for not respecting the > > SPC-2/3/4 requirement for 'INQUIRY data (see table ...) shall contain at > > least 36 bytes'. As a result we get tons on 'scsi 0:7:1:1: scsi scan: > > INQUIRY result too short (5), using 36' messages on console. This can be > > problematic for slow consoles. Introduce short_inquiry host template flag > > to avoid printing error messages for such adapters. > > > > Signed-off-by: Vitaly Kuznetsov > > --- > > Changes since v1: > > - This is a successor of previously sent "scsi_scan: move 'INQUIRY result > > too short' message to debug level" patch. Instead of moving the message > > to debug level for all adapters introduce a special 'short_inquiry' flag > > for host template [inspired by James Bottomley]. > > James, > > sorry for the ping but can you please let me know your opinion? This is > not a 'cosmetic fix', serial port on Hyper-V is extremely slow and users > get softlockups just because we output too much. Here is a freshly > booted guest with SCSI and FC adapters connected: > > # dmesg | grep -c INQUIRY > 2076 It needs a review ... preferably from someone who validates that we don't get any adverse impact from the missing inquiry data > (my other pernding '[PATCH] scsi_scan: don't dump trace when > scsi_prep_async_scan() is called twice' is related to the same issue). So does this. James > See also: https://lkml.org/lkml/2015/9/6/119 > > Thanks, > > [...] >