Linux-Tegra Archive on
 help / color / Atom feed
From: Thomas Gleixner <>
To: Marc Zyngier <>
	Thierry Reding <>,
	Jonathan Hunter <>,
	Dmitry Osipenko <>,
	Sowjanya Komatineni <>,
	Venkat Reddy Talla <>,
Subject: Re: [PATCH v2 1/4] genirq/irqdomain: Allow partial trimming of irq_data hierarchy
Date: Wed, 07 Oct 2020 14:54:57 +0200
Message-ID: <> (raw)
In-Reply-To: <>

On Wed, Oct 07 2020 at 09:53, Marc Zyngier wrote:
> On 2020-10-07 09:05, Marc Zyngier wrote:
>> On 2020-10-06 21:39, Thomas Gleixner wrote:
>>> This is butt ugly, really. Especially the use case where the tegra PMC
>>> domain removes itself from the hierarchy from .alloc()
>> I don't disagree at all. It is both horrible and dangerous.
>> My preference would have been to split the PMC domain into discrete
>> domains, each one having having its own depth. But that's incredibly
>> hard to express in DT, and would break the combination of old/new
>> DT and kernel.


>>> That said, I don't have a better idea either. Sigh...
>> A (very minor) improvement would be to turn the trim call in the PMC
>> driver into a flag set in the first invalid irq_data structure, and
>> let __irq_domain_alloc_irqs() do the dirty work.
>> Still crap, but at least would prevent some form of abuse. Thoughts?
> Actually, I wonder whether we can have a more general approach:
> A partial hierarchy that doesn't have an irq_data->chip pointer
> populated cannot be valid. So I wonder if the least ugly thing to do
> is to just drop any messing about in the PMC driver, and instead to
> let __irq_domain_alloc_irqs() do the culling, always, by looking for a
> NULL pointer in irq_data->chip.
> Not any less ugly, but at least doesn't need any driver intervention.

I like that approach.



  parent reply index

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-06 10:11 [PATCH v2 0/4] soc/tegra: Prevent the PMC driver from corrupting interrupt routing Marc Zyngier
2020-10-06 10:11 ` [PATCH v2 1/4] genirq/irqdomain: Allow partial trimming of irq_data hierarchy Marc Zyngier
2020-10-06 20:39   ` Thomas Gleixner
2020-10-07  8:05     ` Marc Zyngier
2020-10-07  8:53       ` Marc Zyngier
2020-10-07 12:23         ` Marc Zyngier
2020-10-07 12:54         ` Thomas Gleixner [this message]
2020-10-06 10:11 ` [PATCH v2 2/4] gpio: tegra186: Allow optional irq parent callbacks Marc Zyngier
2020-10-06 10:11 ` [PATCH v2 3/4] soc/tegra: pmc: " Marc Zyngier
2020-10-06 10:11 ` [PATCH v2 4/4] soc/tegra: pmc: Don't create fake interrupt hierarchy levels Marc Zyngier
2020-10-06 12:39 ` [PATCH v2 0/4] soc/tegra: Prevent the PMC driver from corrupting interrupt routing Thierry Reding

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:

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

  git send-email \ \ \ \ \ \ \ \ \ \ \ \ \

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-Tegra Archive on

Archives are clonable:
	git clone --mirror linux-tegra/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-tegra linux-tegra/ \
	public-inbox-index linux-tegra

Example config snippet for mirrors

Newsgroup available over NNTP:

AGPL code for this site: git clone