From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: blk-mq problem on proliant DL380 G3 (cciss) Date: Wed, 29 Oct 2014 14:13:46 -0600 Message-ID: <54514A7A.8050008@kernel.dk> References: <545102FE.3010003@kernel.dk> <20141029183828.GA31689@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-pa0-f51.google.com ([209.85.220.51]:44602 "EHLO mail-pa0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755980AbaJ2UNr (ORCPT ); Wed, 29 Oct 2014 16:13:47 -0400 Received: by mail-pa0-f51.google.com with SMTP id kq14so3841399pab.24 for ; Wed, 29 Oct 2014 13:13:46 -0700 (PDT) In-Reply-To: Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Meelis Roos , Christoph Hellwig Cc: linux-scsi@vger.kernel.org On 10/29/2014 02:06 PM, Meelis Roos wrote: >> On Wed, Oct 29, 2014 at 09:08:46AM -0600, Jens Axboe wrote: >>>> Another test server with MPT SCSI RAID has similar problem, >>>> scsi_mode.use_blk_mq=0 cures it but I can not get good trace (no serail >>>> console). 3.18.0-rc2-00043-gf7e87a4 was tested there. >>> >>> The first issue looks like scsi cdrom and error handling, it must be leaking >>> requests hence we hang on allocation of a new one. cciss doesn't use blk_mq >>> regardless of the scsi setting. Does the mpt box also have a libata driven >>> cdrom? >> >> cciss does use scsi for CDROMs and other external devices, it is a bit >> of a mess. >> >> Meelis, did you also test scsi-mq on 3.17 and this is a regression, or >> was 3.18-rc2 the first kernel you tested? > > Both machines ran 3.17 successfully. I turned on scsi-mq option as soon > as it appeared in Kconfig as a new option. But I am not sure whan the > option appeared, before or after 3.17 release. So just to be fully clear, you never enabled scsi-mq on 3.17? To do that, you would have had to add a scsi_mod.use_blk_mq=1 boot parameter. The scsi-mq kconfig option did not show up until after 3.17 release. -- Jens Axboe