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From: Thomas Gleixner <tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org>
To: LKML <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
Cc: Heiko Stuebner <heiko-4mtYJXux2i+zQB+pC5nmwQ@public.gmane.org>,
	Julia Cartwright <julia-acOepvfBmUk@public.gmane.org>,
	Marc Zyngier <marc.zyngier-5wv7dgnIgG8@public.gmane.org>,
	Linus Walleij
	<linus.walleij-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>,
	Brian Norris
	<briannorris-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>,
	Doug Anderson <dianders-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>,
	linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org,
	John Keeping <john-HooS5bfzL4hWk0Htik3J/w@public.gmane.org>,
	linux-gpio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: [patch 0/5] genirq: Distangle irq_request/release_resources() from irq_desc->lock
Date: Thu, 29 Jun 2017 23:33:34 +0200	[thread overview]
Message-ID: <20170629213334.375848050@linutronix.de> (raw)

The irq_request/release_resources() callbacks are a problem on RT as they
are called under irq_desc->lock with interrupts disabled.

Aside of that calling them under irq_desc->lock is conceptually wrong and
has a (hard to trigger and probably theoretical) issue in free_irq(). See
patch 4/5 for a detailed explanation.

The series contains also a fix for the exynos gpio driver, which fiddles
with the irq masking in the resource callbacks, which is bogus and
potentially harmful.

Finally it moves the irq timings deallocation out of the spin locked region.

Thanks,

	tglx
---
 drivers/pinctrl/samsung/pinctrl-exynos.c |    4 --
 include/linux/irqdesc.h                  |    3 +
 kernel/irq/irqdesc.c                     |    1 
 kernel/irq/manage.c                      |   47 +++++++++++++++++++------------
 4 files changed, 34 insertions(+), 21 deletions(-)

             reply	other threads:[~2017-06-29 21:33 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-06-29 21:33 Thomas Gleixner [this message]
2017-06-29 21:33 ` [patch 1/5] pinctrl: samsung: Remove bogus irq_[un]mask from resource management Thomas Gleixner
2017-06-30  2:47   ` Tomasz Figa
2017-06-30  6:02     ` Krzysztof Kozlowski
2017-06-30  6:20       ` Tomasz Figa
     [not found]   ` <20170629214343.882576048-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org>
2017-06-30 12:12     ` Linus Walleij
2017-06-30 12:17       ` Thomas Gleixner
2017-06-30 13:53   ` Linus Walleij
2017-06-30 14:58     ` Krzysztof Kozlowski
2017-06-29 21:33 ` [patch 2/5] genirq: Move bus locking into __setup_irq() Thomas Gleixner
2017-06-29 21:33 ` [patch 3/5] genirq: Add mutex to irq desc to serialize request/free_irq() Thomas Gleixner
2017-06-29 21:33 ` [patch 4/5] genirq: Move irq resource handling out of spinlocked region Thomas Gleixner
2017-06-29 21:33 ` [patch 5/5] genirq/timings: Move free timings " Thomas Gleixner
2017-06-30 13:49 ` [patch 0/5] genirq: Distangle irq_request/release_resources() from irq_desc->lock Marc Zyngier

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