Re: Top kernel oopses/warnings for the week of May 30th 2008

[Arjan van de Ven]

Linus Torvalds wrote:
> On Fri, 30 May 2008, Arjan van de Ven wrote:
> > ok for some it did gather this information, and it is
> >
> > kernel BUG at mm/highmem.c:319!
>
> That's just _odd_. The call chain actually has kmap() in it, and kmap 
> does:
>
> 	if (!PageHighMem(page))
> 		return page_address(page);
> 	return kmap_high(page);
>
> so if it's the one at line 319, which says
>
> 	BUG_ON(!PageHighMem(page));
>
> then I wonder what happened to that PageHighMem() test of the page in 
> between..
>
> Ahh.. Not the same "page". It looks like it's in the 
> flush_all_zero_pkmaps() path, and it's clearing some _other_ page in the 
> pkmap table in order to make room for the new one. So the page that causes 
> problems is from here:
>
> 	 page = pte_page(pkmap_page_table[i]);
>
> rather than the one we're trying to map.
>
> Not that it explains the BUG_ON(). We should only insert page table 
> entries into the pkmap_page_table[] array in map_new_virtual(), which in 
> turn is only called from kmap_high(), which in turn means that *those* 
> pages have also gine through the PageHighMem() test.
>
> So it sounds like we either
>  - have corruption in pkmap_page_table[]
>  - or pte_page() doesn't reverse mk_pte(page) propely, and one or the 
>    other is broken.
>
> Does anybody know if the fc9 x86-32 kernel is built with PAE enabled? 

versions that do identify themselves as "2.6.25-14.fc9.i686.PAE", and these ones didn't,
(they're all in the "2.6.25-14.fc9.i686" form) so this is a kernel without PAE.
--
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/