Hi Oliver,
Good spot. Thanks.
The control transfers are not used very often so this bug remained
hidden for so long. This patch hopefully fix it plus one more.
Comments?
later,
Petko
--- Oliver Neukum <[EMAIL PROTECTED]> wrote:
> Hi Petkan, hi list,
>
> I believe there's a race that may lead to a lost
> wake_up between
> get_registers() and cousins in
>
> while ( pegasus->flags & ETH_REGS_CHANGED ) {
> pegasus->flags |= CTRL_URB_SLEEP;
> interruptible_sleep_on( &pegasus->ctrl_wait );
> }
>
> with the following lines from ctrl_callback
>
> if ( pegasus->flags & CTRL_URB_SLEEP ) {
> pegasus->flags &= ~CTRL_URB_SLEEP;
> wake_up_interruptible( &pegasus->ctrl_wait );
> }
>
> To be precise, if the interrupt happens exactly
>
> while ( pegasus->flags & ETH_REGS_CHANGED ) {
> pegasus->flags |= CTRL_URB_SLEEP;
> ----------> here
> interruptible_sleep_on( &pegasus->ctrl_wait );
>
> ,you are screwed.
>
> HTH
> Oliver
pegasus.c.diff
