Re: [PATCH 1/3] Input: sysrq - drop tty argument from sysrq opshandlers

From: Benjamin Herrenschmidt
Date: Wed Aug 04 2010 - 22:03:33 EST


On Wed, 2010-08-04 at 07:03 -0500, Jason Wessel wrote:
> The usb serial has the same kind of problem with all sorts of locks.
> I
> had resorted to using a tasklet or workqueue to get the sysrq to
> execute
> just outside the usb serial driver context. This work never made it
> upstream because it was part of another series, but the reference is:
> http://lkml.org/lkml/2010/3/9/17
>
> For the standard serial you might be able to get away with dropping
> the
> lock for the sysrq.
>
> Did you have a particular way to trigger the problem or was it just
> completely random, because I don't know that I have observed this
> behavior with the typical 8250 driver.

Yes, I do actually :-) A 64-way machine and a bunch of processes
flooding the console will do it just fine :-)

Cheers,
Ben.


--
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/