linux-pci.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Marc Zyngier <maz@kernel.org>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: LKML <linux-kernel@vger.kernel.org>,
	x86@kernel.org, Bjorn Helgaas <bhelgaas@google.com>,
	linux-pci@vger.kernel.org, Keith Busch <kbusch@kernel.org>,
	Kuppuswamy Sathyanarayanan 
	<sathyanarayanan.kuppuswamy@linux.intel.com>
Subject: Re: [patch 6/7] genirq: Provide interrupt injection mechanism
Date: Fri, 06 Mar 2020 13:52:10 +0000	[thread overview]
Message-ID: <772fa52c32de3ca3229d2df3a32cc643@kernel.org> (raw)
In-Reply-To: <20200306130623.990928309@linutronix.de>

On 2020-03-06 13:03, Thomas Gleixner wrote:
> Error injection mechanisms need a half ways safe way to inject 
> interrupts as
> invoking generic_handle_irq() or the actual device interrupt handler
> directly from e.g. a debugfs write is not guaranteed to be safe.
> 
> On x86 generic_handle_irq() is unsafe due to the hardware trainwreck 
> which
> is the base of x86 interrupt delivery and affinity management.
> 
> Move the irq debugfs injection code into a separate function which can 
> be
> used by error injection code as well.
> 
> The implementation prevents at least that state is corrupted, but it 
> cannot
> close a very tiny race window on x86 which might result in a stale and 
> not
> serviced device interrupt under very unlikely circumstances.
> 
> This is explicitly for debugging and testing and not for production use 
> or
> abuse in random driver code.
> 
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Acked-by: Marc Zyngier <maz@kernel.org>

         M.
-- 
Jazz is not dead. It just smells funny...

  reply	other threads:[~2020-03-06 13:52 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-06 13:03 [patch 0/7] genirq/PCI: Sanitize interrupt injection Thomas Gleixner
2020-03-06 13:03 ` [patch 1/7] genirq/debugfs: Add missing sanity checks to " Thomas Gleixner
2020-03-06 13:15   ` Marc Zyngier
2020-03-06 13:03 ` [patch 2/7] genirq: Add protection against unsafe usage of generic_handle_irq() Thomas Gleixner
2020-03-06 13:36   ` Marc Zyngier
2020-03-06 13:03 ` [patch 3/7] x86/apic/vector: Force interupt handler invocation to irq context Thomas Gleixner
2020-03-06 13:03 ` [patch 4/7] genirq: Add return value to check_irq_resend() Thomas Gleixner
2020-03-06 13:44   ` Marc Zyngier
2020-03-06 13:03 ` [patch 5/7] genirq: Sanitize state handling in check_irq_resend() Thomas Gleixner
2020-03-06 13:46   ` Marc Zyngier
2020-03-06 13:03 ` [patch 6/7] genirq: Provide interrupt injection mechanism Thomas Gleixner
2020-03-06 13:52   ` Marc Zyngier [this message]
2020-03-06 18:34   ` Kuppuswamy Sathyanarayanan
2020-03-06 13:03 ` [patch 7/7] PCI/AER: Fix the broken interrupt injection Thomas Gleixner
2020-03-06 18:32   ` Kuppuswamy Sathyanarayanan
2020-03-06 19:29     ` Kuppuswamy Sathyanarayanan

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=772fa52c32de3ca3229d2df3a32cc643@kernel.org \
    --to=maz@kernel.org \
    --cc=bhelgaas@google.com \
    --cc=kbusch@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=sathyanarayanan.kuppuswamy@linux.intel.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;
as well as URLs for NNTP newsgroup(s).