Re: IDE Hotswap

[Alan Cox <alan@lxorguk.ukuu.org.uk>]

On Mer, 2004-09-29 at 19:20, Bartlomiej Zolnierkiewicz wrote:
> > Doesn't occur in the 2.4 situation or the 2.6 stuff with the locking in
> > the 2.6.8.1-ac patch.
> 
> I will verify this in a few days, I have some real work to do first.

2.6 is the important stuff sure.

> > > - double unlock obvious mistake
> > Details ?
> 
> 2003/08/16 alan               | 	/* Drive shutdown sequence done */
> 2003/08/16 alan               | 	/* Prevent new opens ?? */
> 2003/08/16 alan               | 	spin_unlock_irqrestore(&io_request_lock, flags);
> 2003/08/16 alan               | 	/*
> 2003/08/16 alan               | 	 * Flush kernel side caches, and dump the /proc files
> 2003/08/16 alan               | 	 */
> 2003/08/16 alan               | 	spin_unlock_irqrestore(&io_request_lock, flags);
> 

Thanks. I'll go over this when I dig out the one little bit 2.4.2x needs
for hotplug to behave right with hard disks that I should get to
Marcelo.

> OK BKL protects us against i.e. concurrent HDIO_GETGEO
> and hotplug ioctl.  There is however no protection for controller
> hotplug.

Agreed.