From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Subject: Re: [PATCH] scsi: lpfc: Add shutdown method for kexec Date: Tue, 14 Feb 2017 13:04:46 +1100 Message-ID: <1487037886.23576.16.camel@kernel.crashing.org> References: <20170212214920.28866-1-anton@ozlabs.org> <1486941294.3401.67.camel@kernel.crashing.org> <20170213104723.7741de0a@kryten> <87efz3hre6.fsf@xmission.com> <1486947669.3401.69.camel@kernel.crashing.org> <2fa7fc70-44d4-f536-befb-8a7849741fb7@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from gate.crashing.org ([63.228.1.57]:39279 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750946AbdBND2h (ORCPT ); Mon, 13 Feb 2017 22:28:37 -0500 In-Reply-To: <2fa7fc70-44d4-f536-befb-8a7849741fb7@linux.vnet.ibm.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Brian King , "Eric W. Biederman" , Anton Blanchard Cc: james.smart@broadcom.com, dick.kennedy@broadcom.com, jejb@linux.vnet.ibm.com, martin.petersen@oracle.com, jk@ozlabs.org, linux-scsi@vger.kernel.org On Mon, 2017-02-13 at 15:57 -0600, Brian King wrote: > If we do transition to use remove rather than shutdown, I think we > want > some way for a device driver to know whether we are doing kexec or > not. > A RAID adapter with a write cache is going to want to flush its write > cache on a PCI hotplug remove, but for a kexec, its going to want to > skip > that so the kexec is faster. Today, since kexec looks like a reboot, > rather than a shutdown, we can skip the flush on a reboot, since its > technically not needed there either. What happens if a non-flushed adapter gets a PERST ? I wouldn't trust that 'don't have to flush' magic ... Cheers, Ben.