From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from out01.mta.xmission.com ([166.70.13.231]) by bombadil.infradead.org with esmtp (Exim 4.72 #1 (Red Hat Linux)) id 1OehQI-00054z-DU for kexec@lists.infradead.org; Fri, 30 Jul 2010 04:42:19 +0000 Subject: Re: In place kexec References: <4C50A7AD.8040902@zytor.com> <20100729134343.GA31490@shamino.rdu.redhat.com> <4C519853.2040206@zytor.com> <20100729150640.GF31490@shamino.rdu.redhat.com> <4C51BFA5.60507@zytor.com> <4C51C878.2090102@zytor.com> <20100729191654.GB28704@redhat.com> <20100729125535.85dfd7da.randy.dunlap@oracle.com> <4C524934.5070806@zytor.com> From: ebiederm@xmission.com (Eric W. Biederman) Date: Thu, 29 Jul 2010 21:41:59 -0700 In-Reply-To: <4C524934.5070806@zytor.com> (H. Peter Anvin's message of "Thu\, 29 Jul 2010 20\:38\:28 -0700") Message-ID: MIME-Version: 1.0 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: "H. Peter Anvin" Cc: Randy Dunlap , Neil Horman , "kexec@lists.infradead.org" , Simon Horman , Andrew Vasquez , linux-driver@qlogic.com, Vivek Goyal "H. Peter Anvin" writes: > On 07/29/2010 12:55 PM, Randy Dunlap wrote: >>> >>> And device_shutdown calls every drivers .shutdown method. >>> >>> Things like this are always a driver problem. >> >> so is there a default .shutdown method for drivers that do not specify one? >> >> like the qla2xxx driver does not. >> > > If it doesn't, even if bus mastering gets shut off at the core level, > there is a risk that is clobbers data when it turns it back on if the > initialization sequence is problematic. There isn't a bus master shut off at the core level. When we did the original analysis it turned out that the bus mastering bit was implemented on a lot of devices in advisory way, so it didn't make sense to count on it. That said it looks like the code to do the shutdown is in qla2x00_remove_one so it should be too hard if someone cared to extract just the hardware bits. Eric _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec