On Wed, 10 Oct 2007 18:52:24 -0400 Philippe Rétornaz <[EMAIL PROTECTED]> wrote:
> As explained on: > http://www.avrfreaks.net/index.php?name=PNphpBB2&file=viewtopic&t=53307 > If the current process is preempted before it can copy RAR_SUP and > RSR_SUP both register are lost and the process will segfault as soon > as it return from the syscall since the return adress will be > corrupted. > > This patch disable IRQ as soon as we enter the syscall path and > reenable them when the copy is done. > > In the interrupt handlers, check if we are interrupting the srrf > instruction, if so disable interrupts and return. The interrupt > handler will be re-called immediatly when the interrupts are > reenabled. Just to make it clear: It will disable interrupts in the return context, so interrupts will be disabled when the interrupt handler returns. > After some stressing workload: > - find / > /dev/null in loop > - top (in ssh) > - ping -f avr32 > > The segfaults are not seen anymore. > > Signed-off-by: Philippe Rétornaz <[EMAIL PROTECTED]> Nice work. The patch looks correct as far as I can tell, so I think I'll merge it as soon as possible, and perhaps enable CONFIG_PREEMPT in the defconfig, to give it some more exposure. Thanks! Håvard - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
