Re: Linux 2.6.26-rc4

[Arjan van de Ven <arjan@infradead.org>]

On Tue, 27 May 2008 06:43:51 +0100
David Woodhouse <dwmw2@infradead.org> wrote:

> On Mon, 2008-05-26 at 17:25 -0700, Arjan van de Ven wrote:
> > btw this guy has shown up on kerneloops.org a lot: 
> > http://www.kerneloops.org/searchweek.php?search=__ioremap_caller
> > where it's trying to map memory as uncachable, which is.. well nasty
> > (it seems to map not just the piece it needs, but more, and then
> > turns that "more" uncachable, even if the kernel is using it for
> > "normal" things)
> 
> The driver needs that 'more' to reach the lock registers for the flash
> chip. If it's being used for other things, shouldn't the
> request_region() fail?

it does fail....
... and then the driver continues anyway!

        if (request_resource(&iomem_resource, &window->rsrc)) {
                window->rsrc.parent = NULL;
                printk(KERN_ERR MOD_NAME   
                        " %s(): Unable to register resource"
                        " 0x%.016llx-0x%.016llx - kernel bug?\n",
                        __func__,
                        (unsigned long long)window->rsrc.start,
                        (unsigned long long)window->rsrc.end); 
        }

notice the lack of "return" or "goto out" etc ;)

> 
> On a vaguely related note, there's a lot to be said for _not_ using
> the standard PCI driver setup on the BIOS flash drivers, and going
> back to having them manually loaded rather than being automatically
> loaded whenever the appropriate southbridge is present.
> 
> It would be nicer if the only people who have write access to their
> BIOS flash are the ones who _really_ wanted it.

absolutely

do we need a MODULE_NO_AUTOLOAD() ?

> 


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