From: Andrea Righi <andrea.righi@canonical.com>
To: Pavel Machek <pavel@ucw.cz>
Cc: Boqun Feng <boqun.feng@gmail.com>, Dan Murphy <dmurphy@ti.com>,
linux-leds@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] leds: trigger: fix potential deadlock with libata
Date: Wed, 25 Nov 2020 16:20:42 +0100 [thread overview]
Message-ID: <20201125152042.GC73489@xps-13-7390> (raw)
In-Reply-To: <20201125141517.GA73489@xps-13-7390>
On Wed, Nov 25, 2020 at 03:15:18PM +0100, Andrea Righi wrote:
...
> > I'd hate to see this in stable 3 days after Linus merges it...
> >
> > Do these need _irqsave, too?
> >
> > drivers/leds/led-triggers.c: read_lock(&trig->leddev_list_lock);
> > drivers/leds/led-triggers.c: read_unlock(&trig->leddev_list_lock);
> > drivers/leds/led-triggers.c: read_lock(&trig->leddev_list_lock);
> > drivers/leds/led-triggers.c: read_unlock(&trig->leddev_list_lock);
> >
> > Best regards,
>
> I think also led_trigger_blink_setup() needs to use irqsave/irqrestore,
> in fact:
>
> $ git grep "led_trigger_blink("
> drivers/leds/led-triggers.c:void led_trigger_blink(struct led_trigger *trig,
> drivers/power/supply/power_supply_leds.c: led_trigger_blink(psy->charging_blink_full_solid_trig,
> include/linux/leds.h:void led_trigger_blink(struct led_trigger *trigger, unsigned long *delay_on,
> include/linux/leds.h:static inline void led_trigger_blink(struct led_trigger *trigger,
>
> power_supply_leds.c is using led_trigger_blink() from a workqueue
> context, so potentially the same deadlock condition can also happen.
>
> Let me know if you want me to send a new patch to include also this
> case.
Just sent (and tested) a v2 of this patch that changes also
led_trigger_blink_setup().
-Andrea
next prev parent reply other threads:[~2020-11-25 15:20 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-02 10:41 Andrea Righi
2020-11-25 12:46 ` Pavel Machek
2020-11-25 14:01 ` Boqun Feng
2020-11-25 14:15 ` Andrea Righi
2020-11-25 15:20 ` Andrea Righi [this message]
2021-03-06 20:39 ` Marc Kleine-Budde
2021-03-07 2:02 ` Boqun Feng
2021-03-07 7:14 ` Andrea Righi
2021-03-08 14:56 ` Marc Kleine-Budde
2021-03-08 15:05 ` Marc Kleine-Budde
2021-03-07 16:13 ` Pavel Machek
2021-03-07 19:04 ` Hans de Goede
2021-03-07 16:26 ` Pavel Machek
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