Re: [PATCH] Make math_state_restore() save and restore the interruptflag

From: H. Peter Anvin
Date: Sat Feb 01 2014 - 15:17:31 EST


On 02/01/2014 11:46 AM, Linus Torvalds wrote:
>
> .. which *does* actually bring up something that might work, and might
> be a good idea: remove the "restore math state or set TS" from the
> normal kernel paths *entirely*, and move it to the "return to user
> space" phase.
>

The task switch code would have to be aware in case of preemption,
though. The nice thing about *that* is that we could probably
completely drop the notion that we can't preempt an FPU-using kernel task.

-hpa

--
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/