Messages in this thread | | | Date | Fri, 18 May 2012 11:06:28 -0700 | From | Greg KH <> | Subject | Re: Race in vt_event_wait() during suspend/resume |
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On Fri, May 18, 2012 at 12:40:51PM +0100, Alan Cox wrote: > On Fri, 18 May 2012 16:34:53 +0530 > Rabin Vincent <rabin@rab.in> wrote: > > > pm_restore_console() is called from the suspend/resume path, > > this calls vt_move_to_console(), which calls vt_event_wait(). > > > > There's a race in this path which causes the process > > which requests the suspend to sleep indefinitely waiting > > for an event which already happened: > > > > P1 P2 > > vt_move_to_console() > > set_console() > > schedule_console_callback() > > vt_waitactive() > > check n == fg_console +1 > > console_callback() > > switch_screen() > > vt_event_post() // no waiters > > > > vt_event_wait() // forever > > > > I think the following should fix it. Comments? > > > > Looks right to me.
Great, Rabin, care to resend it with a proper Signed-off-by: line so that I can apply it?
thanks,
greg k-h
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