From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jitendra Bhivare Subject: RE: [PATCH 1/9] be2iscsi: Fix soft lockup in mgmt_get_all_if_id path using bmbx Date: Tue, 15 Dec 2015 09:33:13 +0530 Message-ID: <4f2e369895ed4be8f460972fd509289e@mail.gmail.com> References: <1450073466-21077-1-git-send-email-jitendra.bhivare@avagotech.com> <1450073466-21077-2-git-send-email-jitendra.bhivare@avagotech.com> <566EDA6C.8030901@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-qk0-f176.google.com ([209.85.220.176]:36504 "EHLO mail-qk0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753057AbbLOEDQ convert rfc822-to-8bit (ORCPT ); Mon, 14 Dec 2015 23:03:16 -0500 Received: by qkht125 with SMTP id t125so169448922qkh.3 for ; Mon, 14 Dec 2015 20:03:14 -0800 (PST) In-Reply-To: <566EDA6C.8030901@suse.de> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Hannes Reinecke , linux-scsi@vger.kernel.org, michaelc@cs.wisc.edu be_mbox_db_ready_wait was changed to remove wait_event_timeout done und= er spinlock held for port initialization FW commands. The timeout change and unrecoverable error check inside the wait loop w= ere needed to be addressed too. Though spinlock was replaced with mutex in patch 2/9. -----Original Message----- =46rom: Hannes Reinecke [mailto:hare@suse.de] Sent: Monday, December 14, 2015 8:34 PM To: Jitendra Bhivare; linux-scsi@vger.kernel.org; michaelc@cs.wisc.edu Subject: Re: [PATCH 1/9] be2iscsi: Fix soft lockup in mgmt_get_all_if_i= d path using bmbx On 12/14/2015 07:10 AM, Jitendra Bhivare wrote: > From: Jitendra > > We are taking mbox_lock spinlock which disables pre-emption before we > poll for mbox completion. Waiting there with spinlock held in excess > of 20s will cause soft lockup. > > Actual fix is to change mbox_lock to mutex. Really? I didn't find that in the patch ... > The changes are done in phases. This is the first part. > 1. Changed mgmt_get_all_if_id to use MCC instead of BMBX. > 2. Changed be_mbox_db_ready_wait to busy wait for 12s max and removed > wait_event_timeout. Added error handling code for IO reads. > OPCODE_COMMON_QUERY_FIRMWARE_CONFIG mbox command takes 8s time when > unreachable boot targets are configured. > Why did you modify be_mbox_db_ready_wait(), seeing that you're not usin= g the mailbox interface anymore after this change? Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage hare@suse.de +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N=C3=BCrnberg GF: F. Imend=C3=B6rffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton H= RB 21284 (AG N=C3=BCrnberg) -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html