mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Jon Hunter <jonathanh@nvidia.com>
To: Marc Zyngier <maz@kernel.org>, Thierry Reding <thierry.reding@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
	linux-tegra@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: IRQ thread timeouts and affinity
Date: Fri, 10 Oct 2025 15:38:59 +0100	[thread overview]
Message-ID: <c7bb79c1-c760-4b44-97c3-86e1c34fff40@nvidia.com> (raw)
In-Reply-To: <86bjmeyh5m.wl-maz@kernel.org>


On 10/10/2025 15:18, Marc Zyngier wrote:

...

> CPU hotplug is the main area of concern, and I'm pretty sure it breaks
> this distribution mechanism (or the other way around). Another thing
> is that if firmware isn't aware that 1:N interrupts can (or should)
> wake-up a CPU from sleep, bad things will happen. Given that nobody
> uses 1:N, you can bet that any bit of privileged SW (TF-A,
> hypervisors) is likely to be buggy (I've already spotted bugs in KVM
> around this).

Thierry, do we ever hotplug CPUs on this device? If not, I am wondering 
if something like this, for now, could only be enabled for devices that 
don't hotplug CPUs. Maybe tied to the kernel config (ie. 
CONFIG_HOTPLUG_CPU)? Just a thought ...

Jon

-- 
nvpublic


  reply	other threads:[~2025-10-10 14:39 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-10-09 11:38 Thierry Reding
2025-10-09 14:30 ` Marc Zyngier
2025-10-09 16:05   ` Thierry Reding
2025-10-09 17:04     ` Marc Zyngier
2025-10-09 18:11       ` Marc Zyngier
2025-10-10 13:50         ` Thierry Reding
2025-10-10 14:18           ` Marc Zyngier
2025-10-10 14:38             ` Jon Hunter [this message]
2025-10-10 14:54               ` Thierry Reding
2025-10-10 15:52                 ` Jon Hunter
2025-10-10 15:03             ` Thierry Reding
2025-10-11 10:00               ` Marc Zyngier
2025-10-14 10:50                 ` Thierry Reding
2025-10-14 11:08                   ` Thierry Reding
2025-10-14 17:46                     ` Marc Zyngier
2025-10-16 18:53 ` Thomas Gleixner

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=c7bb79c1-c760-4b44-97c3-86e1c34fff40@nvidia.com \
    --to=jonathanh@nvidia.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-tegra@vger.kernel.org \
    --cc=maz@kernel.org \
    --cc=tglx@linutronix.de \
    --cc=thierry.reding@gmail.com \
    /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

all inboxes | Powered by JetHome®