From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from va3ehsobe001.messaging.microsoft.com ([216.32.180.11] helo=VA3EHSOBE001.bigfish.com) by bombadil.infradead.org with esmtps (Exim 4.69 #1 (Red Hat Linux)) id 1NzCvs-0000ov-Ll for kexec@lists.infradead.org; Tue, 06 Apr 2010 17:51:25 +0000 Date: Tue, 6 Apr 2010 19:51:06 +0200 From: Joerg Roedel Subject: Re: [PATCH 3/4] Revert "x86: disable IOMMUs on kernel crash" Message-ID: <20100406175106.GH28166@amd.com> References: <20100403012751.834020949@sous-sol.org> <20100403012820.229410717@sous-sol.org> <20100403174128.GQ24846@8bytes.org> <4BB83EAE.5090609@bwalle.de> <20100404085338.GU24846@8bytes.org> <20100404100101.GW24846@8bytes.org> <20100406174257.GG29241@sequoia.sous-sol.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20100406174257.GG29241@sequoia.sous-sol.org> 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: Chris Wright Cc: nhorman@redhat.com, nhorman@tuxdriver.com, Bernhard Walle , Joerg Roedel , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, hbabu@us.ibm.com, iommu@lists.linux-foundation.org, "Eric W. Biederman" , vgoyal@redhat.com On Tue, Apr 06, 2010 at 10:42:57AM -0700, Chris Wright wrote: > * Joerg Roedel (joro@8bytes.org) wrote: > > On Sun, Apr 04, 2010 at 02:44:36AM -0700, Eric W. Biederman wrote: > > > Joerg Roedel writes: > > > > > > > On Sun, Apr 04, 2010 at 09:24:30AM +0200, Bernhard Walle wrote: > > > >> Am 03.04.10 19:49, schrieb Eric W. Biederman: > > > >> > Not a problem. We require a lot of things of the kdump kernel, > > > >> > and it is immediately apparent in a basic sanity test. > > > >> > > > >> Also, in most cases (for example: distribution kernels), the kdump > > > >> kernel nowadays is identical to the running kernel. So, if the running > > > >> kernel has IOMMU support, the kdump kernel also has. > > > > > > > > Yes, I know. But is that a requirement for kexec? > > > > > > For normal kexec no. That path is expected to do a clean hardware > > > shutdown. > > > > > > For kexec on panic aka kdump the requirement is that your your crash > > > kernel be able to initialize your hardware from any state it can be > > > put in. > > > > Ok, if you show me where this is documented for everybody then I am > > probably convinced :-) > > We should fixup the gart initialization anyway. > > So, you planning to pull in all 4 patches then? Yes, I will apply them tomorrow and write a fix for the GART issue this may introduce. Joerg _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec