Linux-HyperV Archive on lore.kernel.org
 help / color / Atom feed
From: Thomas Gleixner <tglx@linutronix.de>
To: David Woodhouse <dwmw2@infradead.org>, x86@kernel.org
Cc: iommu <iommu@lists.linux-foundation.org>,
	kvm <kvm@vger.kernel.org>,
	linux-hyperv@vger.kernel.org, Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH 10/13] x86/irq: Limit IOAPIC and MSI domains' affinity without IR
Date: Wed, 07 Oct 2020 18:02:59 +0200
Message-ID: <877ds23txo.fsf@nanos.tec.linutronix.de> (raw)
In-Reply-To: <1b1fda3079627748e1f5084ddae8a686258c78d9.camel@infradead.org>

On Wed, Oct 07 2020 at 15:23, David Woodhouse wrote:
> On Wed, 2020-10-07 at 16:05 +0200, Thomas Gleixner wrote:
>> On Wed, Oct 07 2020 at 14:08, David Woodhouse wrote:
>> > On 7 October 2020 13:59:00 BST, Thomas Gleixner <tglx@linutronix.de> wrote:
>> > > On Wed, Oct 07 2020 at 08:48, David Woodhouse wrote:
>> > > > To fix *that* case, we really do need the whole series giving us per-
>> > > > domain restricted affinity, and to use it for those MSIs/IOAPICs that
>> > > > the IRQ remapping doesn't cover.
>> > > 
>> > > Which do not exist today.
>> > 
>> > Sure. But at patch 10/13 into this particular patch series, it *does*
>> > exist.
>> 
>> As I told you before: Your ordering is wrong. We do not introduce bugs
>> first and then fix them later ....
>
> I didn't introduce that bug; it's been there for years. Fixing it
> properly requires per-irqdomain affinity limits.
>
> There's a cute little TODO at least in the Intel irq-remapping driver,
> noting that we should probably check if there are any IOAPICs that
> aren't in the scope of any DRHD at all. But that's all.

So someone forgot to remove the cute little TODO when this was added:

       if (parse_ioapics_under_ir()) {
                pr_info("Not enabling interrupt remapping\n");
                goto error;
        }

Thanks,

        tglx

  reply index

Thread overview: 51+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-05 15:28 [PATCH 0/13] Fix per-domain IRQ affinity, allow >255 CPUs on x86 without IRQ remapping David Woodhouse
2020-10-05 15:28 ` [PATCH 01/13] x86/apic: Use x2apic in guest kernels even with unusable CPUs David Woodhouse
2020-10-05 15:28   ` [PATCH 02/13] x86/msi: Only use high bits of MSI address for DMAR unit David Woodhouse
2020-10-06 20:45     ` Thomas Gleixner
2020-10-05 15:28   ` [PATCH 03/13] x86/ioapic: Handle Extended Destination ID field in RTE David Woodhouse
2020-10-05 15:28   ` [PATCH 04/13] x86/apic: Support 15 bits of APIC ID in IOAPIC/MSI where available David Woodhouse
2020-10-05 15:28   ` [PATCH 05/13] genirq: Prepare for default affinity to be passed to __irq_alloc_descs() David Woodhouse
2020-10-06 21:01     ` Thomas Gleixner
2020-10-06 21:07       ` David Woodhouse
2020-10-05 15:28   ` [PATCH 06/13] genirq: Add default_affinity argument " David Woodhouse
2020-10-06 21:06     ` Thomas Gleixner
2020-10-05 15:28   ` [PATCH 07/13] irqdomain: Add max_affinity argument to irq_domain_alloc_descs() David Woodhouse
2020-10-06 21:26     ` Thomas Gleixner
2020-10-07  7:19       ` David Woodhouse
2020-10-07 13:37         ` Thomas Gleixner
2020-10-07 14:10           ` David Woodhouse
2020-10-07 15:57             ` Thomas Gleixner
2020-10-07 16:11               ` David Woodhouse
2020-10-07 20:53                 ` Thomas Gleixner
2020-10-08  7:21               ` David Woodhouse
2020-10-08  9:34                 ` Thomas Gleixner
2020-10-08 11:10                   ` David Woodhouse
2020-10-08 12:40                     ` Thomas Gleixner
2020-10-09  7:54                       ` David Woodhouse
2020-10-05 15:28   ` [PATCH 08/13] genirq: Add irq_domain_set_affinity() David Woodhouse
2020-10-06 21:32     ` Thomas Gleixner
2020-10-07  7:22       ` David Woodhouse
2020-10-05 15:28   ` [PATCH 09/13] x86/irq: Add x86_non_ir_cpumask David Woodhouse
2020-10-06 21:42     ` Thomas Gleixner
2020-10-07  7:25       ` David Woodhouse
2020-10-05 15:28   ` [PATCH 10/13] x86/irq: Limit IOAPIC and MSI domains' affinity without IR David Woodhouse
2020-10-06 21:54     ` Thomas Gleixner
2020-10-07  7:48       ` David Woodhouse
2020-10-07 12:59         ` Thomas Gleixner
2020-10-07 13:08           ` David Woodhouse
2020-10-07 14:05             ` Thomas Gleixner
2020-10-07 14:23               ` David Woodhouse
2020-10-07 16:02                 ` Thomas Gleixner [this message]
2020-10-07 16:15                   ` David Woodhouse
2020-10-07 15:05               ` David Woodhouse
2020-10-07 15:25                 ` Thomas Gleixner
2020-10-07 15:46                   ` David Woodhouse
2020-10-07 17:23                     ` Thomas Gleixner
2020-10-07 17:34                       ` David Woodhouse
2020-10-05 15:28   ` [PATCH 11/13] x86/smp: Allow more than 255 CPUs even without interrupt remapping David Woodhouse
2020-10-05 15:28   ` [PATCH 12/13] iommu/irq_remapping: Kill most of hyperv-iommu.c now it's redundant David Woodhouse
2020-10-05 15:28   ` [PATCH 13/13] x86/kvm: Add KVM_FEATURE_MSI_EXT_DEST_ID David Woodhouse
2020-10-07  8:14     ` Paolo Bonzini
2020-10-07  8:59       ` David Woodhouse
2020-10-07 11:15         ` Paolo Bonzini
2020-10-07 12:04           ` David Woodhouse

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=877ds23txo.fsf@nanos.tec.linutronix.de \
    --to=tglx@linutronix.de \
    --cc=dwmw2@infradead.org \
    --cc=iommu@lists.linux-foundation.org \
    --cc=kvm@vger.kernel.org \
    --cc=linux-hyperv@vger.kernel.org \
    --cc=pbonzini@redhat.com \
    --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

Linux-HyperV Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-hyperv/0 linux-hyperv/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-hyperv linux-hyperv/ https://lore.kernel.org/linux-hyperv \
		linux-hyperv@vger.kernel.org
	public-inbox-index linux-hyperv

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-hyperv


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git