lkml.org 
[lkml]   [2007]   [Jun]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH -mm 2/2] PM: Disable usermode helper before hibernation and suspend
Date
On Friday, 15 June 2007 15:08, Uli Luckas wrote:
> On Monday, 4. June 2007, Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <rjw@sisk.pl>
> >
> > Use a hibernation and suspend notifier to disable the user mode helper
> > before a hibernation/suspend and enable it after the operation.
> >
> Hi Rafael,
> I have a couple of questions, regarding this patch ...
> > - if (!khelper_wq)
> > + if (!khelper_wq || usermodehelper_disabled)
> > return -EBUSY;
> 1) how about not returning -EBUSY here, if (wait == UMH_NO_WAIT)?

Yes, this would make sense.

> 2) how does your patch prevent wait_for_completion(&done) to hang during
> freezing if usermodehelper_pm_callback is called _after_ the above check?

It doesn't. Once the helper is running, we can't distinguish it from any other
user land process.

Still, it narrows the window quite a bit.

Greetings,
Rafael


--
"Premature optimization is the root of all evil." - Donald Knuth
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-06-15 23:33    [W:0.060 / U:0.468 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site