linux-kernel - Re: request_firmware API exhaust memory

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Message-ID: <20100425193658.GA24039@kroah.com>
Date:	Sun, 25 Apr 2010 12:36:58 -0700
From:	Greg KH <greg@...ah.com>
To:	Tomas Winkler <tomasw@...il.com>
Cc:	Johannes Berg <johannes@...solutions.net>,
	Kay Sievers <kay.sievers@...y.org>,
	David Woodhouse <dwmw2@...radead.org>,
	"Rafael J. Wysocki" <rjw@...k.pl>,
	Emmanuel Grumbach <egrumbach@...il.com>,
	linux-kernel@...r.kernel.org
Subject: Re: request_firmware API exhaust memory

On Sun, Apr 25, 2010 at 10:22:54PM +0300, Tomas Winkler wrote:
> On Sun, Apr 25, 2010 at 7:37 PM, Greg KH <greg@...ah.com> wrote:
> > On Thu, Apr 22, 2010 at 01:22:51AM +0300, Tomas Winkler wrote:
> >> On Mon, Apr 19, 2010 at 5:59 PM, Greg KH <greg@...ah.com> wrote:
> >> > On Mon, Apr 19, 2010 at 03:20:34PM +0300, Tomas Winkler wrote:
> >> >> Lately we've been developing a device that rather more extensively
> >> >> used request_firmware API in load and also using pm_notifiers to load
> >> >> firmware.
> >> >
> >> > Do you have a pointer to your driver source anywhere that shows how you
> >> > are trying to use the firmware api in this manner?
> >>
> >> I've attached a very simple ??test driver I'm using. ??Just wanted to
> >> eliminate anything else.
> >> Bellow is a little script that loads and releases the firmware. My
> >> previous observation was wrong.
> >> The free memory gradually decreases regardless of number or dangling
> >> udevd forks, which are eventually collected if the sleep period is
> >> long enough ~10s.
> >
> > That sounds normal for the free memory. ??Kay, that's also to be expected
> > for the udevd forks as well, right?
> 
> Sorry maybe I was not clear what I mean that the memory will be
> eventually exhausted and system will crash
> Is this normal?

Ah, no, that's not normal.  Have you run kmemleak on your module (or
test module) to verify that you are properly freeing up the memory?

> Actually I less suspect now udevd as the same happens on android
> platform where there is no udev

Which is a sad thing for a whole other range of issues...

thanks,

greg k-h
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