Re: [patch] i386: remove IOPL check on task switch

Chuck Ebbert
2006-11-04T00:03:18Z

In-Reply-To: <454B850C.3050402@vmware.com>

On Fri, 03 Nov 2006 10:06:04 -0800, Zachary Amsden wrote:

> Chuck Ebbert wrote:
> > IOPL is implicitly saved and restored on task switch,
> > so explicit check is no longer needed.
>
> Nack. This is used for paravirt-ops kernels that use IOPL'd userspace.

How does that work? In the stock kernel, anything done by
the call to set_iopl_mask() (that was removed by the patch)
will be nullified by the 'popfl' at the end of the switch_to()
macro.

--
Chuck
"Even supernovas have their duller moments."