Re: [PATCH, RESEND] microblaze: Fix level interrupt ACKing

[Steven J. Magnani]

On Fri, 2009-11-20 at 12:07 +0100, Michal Simek wrote:
> Hi Steve,
> 
> steve@xxxxxxxxxxxxxxx wrote:
> > Level interrupts need to be ack'd in the unmask handler, as in powerpc. 
> > Among other issues, this bug causes the system clock to appear to run at 
> > double-speed.
> 
> Can you send me any step-by-step manual how to demonstrate me this 
> fault? If system clock runs at double-speed, then I should be able able 
> to see that time is two times faster. Or do you mean different behavior?

Unless there's a way to read jiffies_64 in userspace, the easiest way I
know of is to use the debugger. Stop the kernel soon after you boot it,
and read jiffies_64. Continue execution for some known amount of
wall-clock time, then stop the kernel again and recheck jiffies_64.
Without the patch, the number of elapsed jiffies is twice what you'd
expect based on HZ.

> 
> Thanks,
> Michal

Regards,
------------------------------------------------------------------------
 Steven J. Magnani               "I claim this network for MARS!
 www.digidescorp.com              Earthling, return my space modulator!"

 #include <standard.disclaimer>



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