From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from terminus.zytor.com ([198.137.202.10] helo=mail.zytor.com) by bombadil.infradead.org with esmtps (Exim 4.72 #1 (Red Hat Linux)) id 1OeUej-0006fB-Mq for kexec@lists.infradead.org; Thu, 29 Jul 2010 15:04:25 +0000 Message-ID: <4C519853.2040206@zytor.com> Date: Thu, 29 Jul 2010 08:03:47 -0700 From: "H. Peter Anvin" MIME-Version: 1.0 Subject: Re: In place kexec References: <4C50A7AD.8040902@zytor.com> <20100729134343.GA31490@shamino.rdu.redhat.com> In-Reply-To: <20100729134343.GA31490@shamino.rdu.redhat.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: kexec-bounces@lists.infradead.org Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Neil Horman Cc: Simon Horman , "kexec@lists.infradead.org" , "Eric W. Biederman" On 07/29/2010 06:43 AM, Neil Horman wrote: > On Wed, Jul 28, 2010 at 03:02:19PM -0700, Eric W. Biederman wrote: >> "H. Peter Anvin" writes: >> >>> We are getting a claim that the qla driver corrupts memory after a >>> kexec, apparently due to a DMA engine left running in the before-kernel. >>> >>> For an in-place kexec (as opposed to a crash dump kexec, where we switch >>> into dedicated memory), what shutdown paths get executed? >> >> It is the normal reboot path, so the device shutdown method gets >> executed. >> >> Eric >> > Check your iommu. We've had lots of problems with them in the past, and in the > crash path we explicity leave the iommu on now, whereas the normal shutdown path > turns it off. If some other dma-capable device doesn't shut down properly and > keeps dma operations going, you're liable to get memory corruption when the > iommu re-initalizes. > Sorry, can we keep the discussions of kexec-on-crash and kexec-in-place clearly separated, please? The qla driver issue is supposed to be kexec-in-place, and it sounds like you're talking about kexec-on-crash. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf. _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec