From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: Re: [PATCH] uas: Limit qdepth at the scsi-host level Date: Sat, 19 Mar 2016 10:06:16 -0700 Message-ID: <1458407176.2288.5.camel@HansenPartnership.com> References: <1458377952-12567-1-git-send-email-hdegoede@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1458377952-12567-1-git-send-email-hdegoede@redhat.com> Sender: stable-owner@vger.kernel.org To: Hans de Goede , Greg Kroah-Hartman , Gerd Hoffmann Cc: Christoph Hellwig , linux-usb@vger.kernel.org, linux-scsi@vger.kernel.org, stable@vger.kernel.org List-Id: linux-scsi@vger.kernel.org On Sat, 2016-03-19 at 09:59 +0100, Hans de Goede wrote: > Commit 64d513ac31bd ("scsi: use host wide tags by default") causes > the scsi-core to queue more cmnds then we can handle on devices with > multiple LUNs, limit the qdepth at the scsi-host level instead of > per slave to fix this. Help me understand this bug a bit more. Are you saying that the commit you identify is causing the block layer to queue more commands than you've set the per-lun limit to? In which case we have a serious problem for more than just UAS. Or are you saying that UAS always had a global command limit, but it just didn't get set correctly; however, it mostly worked until the above commit exposed the problem? James