Re: PnP BIOS driver status

[Brian Gerst <bgerst@didntduck.org>]

Thomas Hood wrote:
> 
> A couple people have asked me about the status of the
> PnP BIOS driver, so I thought I'd post an update.
> 
> History: During the pre-Tosatti 2.4-ac series the driver was
> hammered into a reliable form.  However it never entered the
> mainline kernel series.
> 
> The driver was then stripped down to the core functionality
> required to make the lspnp and setpnp utilities work.
> pnpbios_register_driver() and pnpbios_unregister_driver() are
> still there but aren't used by anything.  Additional /proc/
> interface files were then added to allow reading of ESCD info.
> 
> The latest version of the driver seems nice 'n' stable and can
> be found in Alan's latest 2.4 patches.
> 
> Current 2.5 kernels also contain the driver, but it's a bit out
> of date.  There's a patch in 2.5-dj but that's also out of date.
> ("Out of date" here means "missing new features and some
> cleanups".)  Once DJ releases a 2.5.6-dj I'll send him a patch
> to bring his tree up to date.  Then he can pass it on to Linus.

The current driver is not SMP-safe.  It is modifying the GDT descriptors
outside of the pnp_bios_lock.  Also, you can remove the __cli(), as
spin_lock_irq() already turns off interrupts.

-- 

						Brian Gerst