Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753864Ab3CKDnM (ORCPT ); Sun, 10 Mar 2013 23:43:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:6145 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753697Ab3CKDnL (ORCPT ); Sun, 10 Mar 2013 23:43:11 -0400 Message-ID: <513D52BA.3070206@redhat.com> Date: Mon, 11 Mar 2013 11:42:50 +0800 From: WANG Chao User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130221 Thunderbird/17.0.3 MIME-Version: 1.0 To: Yinghai Lu CC: Vivek Goyal , "Eric W. Biederman" , "H. Peter Anvin" , Shuah Khan , Konrad Rzeszutek Wilk , CAI Qian , LKML , kexec , Dave Young , Takao Indoh Subject: Re: 3.9-rc1: crash kernel panic - not syncing: Can not allocate SWIOTLB buffer earlier and can't now provide you with the DMA bounce buffer References: <51397D1D.5030602@redhat.com> <1750036321.11235774.1362722613994.JavaMail.root@redhat.com>

<51399154.5030500@redhat.com> <51399442.1080609@redhat.com> <5139D5A0.6000600@redhat.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2649 Lines: 69 On 03/09/2013 03:39 AM, Yinghai Lu wrote: > [ Add more to To list ] > > On Fri, Mar 8, 2013 at 10:24 AM, Yinghai Lu wrote: >> On Fri, Mar 8, 2013 at 4:12 AM, WANG Chao wrote: >> >>>> what is 00:02.0 in your system? >>> This IOMMU issue is related to https://lkml.org/lkml/2012/11/26/814. We can >>> discuss this IOMMU issue in that thread. >>> Anyway 00:02.0 is a video card, the box is Ivy Bridge. >>> # lspci -s 00:02.0 -v >>> 00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor >>> Graphics Controller (rev 09) (prog-if 00 [VGA controller]) >>> Subsystem: Intel Corporation Device 2211 >>> Flags: bus master, fast devsel, latency 0, IRQ 44 >>> Memory at afc00000 (64-bit, non-prefetchable) [size=4M] >>> Memory at c0000000 (64-bit, prefetchable) [size=256M] >>> I/O ports at 6000 [size=64] >>> Expansion ROM at [disabled] >>> Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit- >>> Capabilities: [d0] Power Management version 2 >>> Capabilities: [a4] PCI Advanced Features >>> Kernel driver in use: i915 >> >> disable drm for i915 will make your iommu work with dump? >> >>> >>> >>> Is it expected to intel_iommu=on or crashkernel_low to make 2nd kernel boot in >>> 3.9? Back in 3.8, it works just fine w/ only crashkernel param. >> >> Yes, I really do not want to set crashkernel low range like 72M >> automatically for all. >> that would have the system with proper iommu support lose 72M under 4G >> in first kernel. >> And can not play allocate and return tricks, as first kernel have no >> idea if iommu will work >> on second kernel even iommu is working on first kernel. >> >> Better to fix iommu support at first. >> >> For old system that does not have DMAR or kernel does not have IOMMU >> support enabled, or >> user does not pass intel_iommu=on. >> We could set crashkernel low range to 72M automatically. > > It seem that it is not worthy to check case that does not support > IOMMU in second kernel. > > Please check attached patch that will just set crashkernel_low auto, and if the > system DO support iommu with kdump, user can specify crashkernel_low=0 > to save low 72M. The patch works flawlessly on my box! Thank you, Yinghai! Let me know if anything else I can help. WANG Chao > > Thanks > > Yinghai > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/