From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomas Henzl Subject: Re: [PATCH 01/15] megaraid_sas: Do not allow PCI access during OCR Date: Mon, 11 Jan 2016 18:02:03 +0100 Message-ID: <5693E00B.4000403@redhat.com> References: <1450445228-26571-1-git-send-email-Sumit.Saxena@avagotech.com> <1450445228-26571-2-git-send-email-Sumit.Saxena@avagotech.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: Received: from mx1.redhat.com ([209.132.183.28]:51189 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932358AbcAKRCG (ORCPT ); Mon, 11 Jan 2016 12:02:06 -0500 In-Reply-To: <1450445228-26571-2-git-send-email-Sumit.Saxena@avagotech.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Sumit Saxena , jbottomley@parallels.com, hch@infradead.org, martin.petersen@oracle.com Cc: linux-scsi@vger.kernel.org, kashyap.desai@avagotech.com On 18.12.2015 14:26, Sumit Saxena wrote: > This patch will do synhronization between OCR function and AEN function using "reset_mutex" lock. > reset_mutex will be acquire only in first half of the AEN function which issue DCMD. Second half > of the function calls SCSI API (scsi_add_device/scsi_remove_device) should be out of reset_mutex > to avoid deadlock between scsi_eh thread and Driver. > > During chip reset(inside OCR function), there should not be any PCI access and AEN function > (which is called in delayed context) may be firirng DCMDs(doing PCI writes) when chip reset is > happening in parallel which will cause FW fault. This patch will solve the problem by making > AEN thread and OCR thread mutually exclusive. > > Signed-off-by: Sumit Saxena > Signed-off-by: Kashyap Desai You have removed the no more aen_mutex from megasas_instance later in 5/15 , that's ok for me. Reviewed-by: Tomas Henzl Tomas