public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Joerg Roedel <joro@8bytes.org>
To: Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>,
	hpa@zytor.com, x86@kernel.org, Joerg Roedel <joro@8bytes.org>,
	Jiang Liu <jiang.liu@linux.intel.com>,
	Borislav Petkov <bp@alien8.de>
Cc: linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org
Subject: [PATCH 0/5] Fix Intel IRQ remapping initialization order
Date: Mon, 15 Dec 2014 16:13:19 +0100	[thread overview]
Message-ID: <1418656404-28575-1-git-send-email-joro@8bytes.org> (raw)

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.

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(-)

-- 
1.9.1


             reply	other threads:[~2014-12-15 15:13 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-12-15 15:13 Joerg Roedel [this message]
2014-12-15 15:13 ` [PATCH 1/5] iommu/vt-d: Allocate IRQ remapping data structures only for all IOMMUs Joerg Roedel
2014-12-15 15:13 ` [PATCH 2/5] iommu/vt-d: Don't check for ecap_ir_support in intel_irq_remapping_supported Joerg Roedel
2014-12-15 15:13 ` [PATCH 3/5] iommu/vt-d: Move supported-checks to intel_prepare_irq_remapping() Joerg Roedel
2014-12-15 15:13 ` [PATCH 4/5] iommu/amd: Check for irq-remap support amd_iommu_prepare() Joerg Roedel
2014-12-15 15:13 ` [PATCH 5/5] iommu, x86, apic: Remove irq_remapping_supported() Joerg Roedel
2014-12-15 15:30 ` [PATCH 0/5] Fix Intel IRQ remapping initialization order Jiang Liu
2014-12-15 19:54   ` Thomas Gleixner
2014-12-16  1:45     ` Jiang Liu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1418656404-28575-1-git-send-email-joro@8bytes.org \
    --to=joro@8bytes.org \
    --cc=bp@alien8.de \
    --cc=hpa@zytor.com \
    --cc=iommu@lists.linux-foundation.org \
    --cc=jiang.liu@linux.intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=tglx@linutronix.de \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox