[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <20151030152659.GA29070@kroah.com>
Date: Fri, 30 Oct 2015 08:26:59 -0700
From: Greg KH <gregkh@...uxfoundation.org>
To: Lucas De Marchi <lucas.de.marchi@...il.com>
Cc: Mika Westerberg <mika.westerberg@...ux.intel.com>,
Linus Walleij <linus.walleij@...aro.org>,
Mathias Nyman <mathias.nyman@...ux.intel.com>,
Heikki Krogerus <heikki.krogerus@...ux.intel.com>,
"linux-gpio@...r.kernel.org" <linux-gpio@...r.kernel.org>,
lkml <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 2/2] pinctrl: baytrail: Serialize all register access
On Fri, Oct 30, 2015 at 12:48:38PM -0200, Lucas De Marchi wrote:
> Hi Mika and Linus,
>
> CC'ing Greg.
>
> On Tue, Aug 4, 2015 at 9:03 AM, Mika Westerberg
> <mika.westerberg@...ux.intel.com> wrote:
> > There is a hardware issue in Intel Baytrail where concurrent GPIO register
> > access might result reads of 0xffffffff and writes might get dropped
> > completely.
> >
> > Prevent this from happening by taking the serializing lock in all places
> > where it is possible that more than one thread might be accessing the
> > hardware concurrently.
> >
> > Signed-off-by: Mika Westerberg <mika.westerberg@...ux.intel.com>
> > ---
>
> Now that this is on 4.2, can we get it on stable branches? I was
> hitting this bug for some time on MinnowBoard Max and this week I had
> some time to take a look on how to fix it. Good timing, it had already
> been fixed. Applying this patch the issue is gone on top of 4.1.12.
>
> I'm using these patches from Linus Torvalds' tree:
> 39ce815 pinctrl: baytrail: Serialize all register access
> 78e1c89 pinctrl: baytrail: Use raw_spinlock for locking
>
>
> The ones to Cherryview could be sent too but I couldn't test them.
>
> Leaving the patch below for reference.
<formletter>
This is not the correct way to submit patches for inclusion in the
stable kernel tree. Please read Documentation/stable_kernel_rules.txt
for how to do this properly.
</formletter>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists