Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757458Ab0DVTta (ORCPT ); Thu, 22 Apr 2010 15:49:30 -0400 Received: from kroah.org ([198.145.64.141]:41042 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756566Ab0DVT2z (ORCPT ); Thu, 22 Apr 2010 15:28:55 -0400 X-Mailbox-Line: From gregkh@kvm.kroah.org Thu Apr 22 12:09:17 2010 Message-Id: <20100422190916.931886465@kvm.kroah.org> User-Agent: quilt/0.48-4.4 Date: Thu, 22 Apr 2010 12:09:18 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Neil Horman , Vivek Goyal , Chris Wright , Joerg Roedel Subject: [107/197] x86/amd-iommu: enable iommu before attaching devices In-Reply-To: <20100422191857.GA13268@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1956 Lines: 64 2.6.32-stable review patch. If anyone has any objections, please let us know. ------------------ From: Chris Wright commit 75f66533bc883f761a7adcab3281fe3323efbc90 upstream. Hit another kdump problem as reported by Neil Horman. When initializaing the IOMMU, we attach devices to their domains before the IOMMU is fully (re)initialized. Attaching a device will issue some important invalidations. In the context of the newly kexec'd kdump kernel, the IOMMU may have stale cached data from the original kernel. Because we do the attach too early, the invalidation commands are placed in the new command buffer before the IOMMU is updated w/ that buffer. This leaves the stale entries in the kdump context and can renders device unusable. Simply enable the IOMMU before we do the attach. Cc: Neil Horman Cc: Vivek Goyal Signed-off-by: Chris Wright Signed-off-by: Joerg Roedel Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/amd_iommu_init.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/arch/x86/kernel/amd_iommu_init.c +++ b/arch/x86/kernel/amd_iommu_init.c @@ -1284,6 +1284,8 @@ int __init amd_iommu_init(void) if (ret) goto free; + enable_iommus(); + if (iommu_pass_through) ret = amd_iommu_init_passthrough(); else @@ -1294,8 +1296,6 @@ int __init amd_iommu_init(void) amd_iommu_init_api(); - enable_iommus(); - if (iommu_pass_through) goto out; @@ -1314,6 +1314,8 @@ out: return ret; free: + disable_iommus(); + free_pages((unsigned long)amd_iommu_pd_alloc_bitmap, get_order(MAX_DOMAIN_ID/8)); -- 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/