lkml.org 
[lkml]   [2014]   [Jul]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v11 0/2] Add support for the Allwinner A31 DMA Controller
On Fri, Jul 25, 2014 at 06:37:46PM +0200, Maxime Ripard wrote:
> Hi Vinod,
>
> On Fri, Jul 25, 2014 at 06:42:17PM +0530, Vinod Koul wrote:
> > - don't use devm_request_irq(). You have irq enabled and you have killed
> > tasklet. This is too racy. You need to ensure no irqs can be generated before killing
> > tasklets.
>
> Ok, would calling disable_irq before killing the tasklet an option for
> you ? that would allow to keep the devm_request_irq.

That's not really an acceptable approach if you can use shared interrupts.
A better alternative would be devm_free_irq() to give a definite point
that the interrupt is unregistered in the driver remove sequence. That
allows you to keep the advantage of devm_request_irq() to clean up during
the initialisation side.

An alternative approach would be to ensure that the hardware is quiesced,
and interrupts are disabled. Then call synchronize_irq() on it, and at
that point, you should be certain that your interrupt handler should not
process any further interrupts for your device (though, in a shared
interrupt environment, it would still be called should a different device
on the shared line raise its interrupt.)

--
FTTC broadband for 0.8mile line: currently at 9.5Mbps down 400kbps up
according to speedtest.net.


\
 
 \ /
  Last update: 2014-07-25 21:01    [W:0.073 / U:0.092 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site