From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiang Liu Subject: Re: [PATCH 0/5] Fix Intel IRQ remapping initialization order Date: Mon, 15 Dec 2014 23:30:16 +0800 Message-ID: <548EFE88.3000307@linux.intel.com> References: <1418656404-28575-1-git-send-email-joro@8bytes.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1418656404-28575-1-git-send-email-joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Joerg Roedel , Thomas Gleixner , Ingo Molnar , hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org, x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, Borislav Petkov Cc: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: iommu@lists.linux-foundation.org On 2014/12/15 23:13, Joerg Roedel wrote: > Hi, > > here is a patch-set against tip/x86/apic to fix an initialization order > problem with the IRQ remapping code. The problem is in the ordering of > the irq_remapping_prepare and irq_remapping_supported functions. > > Currently the call-order is irq_remapping_prepare -> > irq_remapping_supported, so that 'prepare' can succeed but 'supported' > fails, so that interrupt remapping gets initialized but not enabled. > This causes a broken interrupt setup on affected systems (machines with > an Intel IOMMU without, or broken, IRQ remapping support). The result > are lost interrupts and a non-bootable system. > > Both functions do checks whether IRQ remapping can be enabled on the > machine. The reason for this is that some checks rely on > dmar_table_init() and thus have to be done in irq_remapping_prepare(). > > This patch-set moves all these checks into the irq_remapping_prepare() > path with the right ordering and removes the irq_remapping_supported() > function and its call-backs. This fixes the initializion order problem > and simplifies the exported API from the IOMMU code. > > Please review. Hi Joerg, I have posted a patch set for the same purpose at: https://lkml.org/lkml/2014/12/10/20 Seems we need to combine these two patch sets:) Regards! Gerry > > Thanks, > > Joerg > > Joerg Roedel (5): > iommu/vt-d: Allocate IRQ remapping data structures only for all IOMMUs > iommu/vt-d: Don't check for ecap_ir_support in > intel_irq_remapping_supported > iommu/vt-d: Move supported-checks to intel_prepare_irq_remapping() > iommu/amd: Check for irq-remap support amd_iommu_prepare() > iommu, x86, apic: Remove irq_remapping_supported() > > arch/x86/kernel/apic/apic.c | 5 --- > drivers/iommu/amd_iommu.c | 1 - > drivers/iommu/amd_iommu_init.c | 8 ++--- > drivers/iommu/amd_iommu_proto.h | 1 - > drivers/iommu/intel_irq_remapping.c | 62 +++++++++++++++++-------------------- > drivers/iommu/irq_remapping.c | 11 ------- > drivers/iommu/irq_remapping.h | 3 -- > 7 files changed, 31 insertions(+), 60 deletions(-) >