Messages in this thread | | | Date | Wed, 19 Sep 2007 21:46:41 +0200 | From | Jiri Slaby <> | Subject | Re: X-freeze after clflush changes [Was: 2.6.23-rc6-mm1] |
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On 09/19/2007 09:24 PM, Andi Kleen wrote: > On Wed, Sep 19, 2007 at 12:10:17PM -0700, Andrew Morton wrote: >> On Wed, 19 Sep 2007 16:59:04 +0200 Jiri Slaby <jirislaby@gmail.com> wrote: >> >>> ---------8<---------8<---------8<---------8<---------8<---------8<---- >>> That means >>> void agp_generic_destroy_page(void *addr) >>> { >>> struct page *page; >>> >>> if (addr == NULL) >>> return; >>> >>> page = virt_to_page(addr); >>> (1) unmap_page_from_agp(page); >>> put_page(page); >>> (2) free_page((unsigned long)addr); >>> atomic_dec(&agp_bridge->current_memory_agp); >>> } >>> >>> (1) unmap_page_from_agp -> change_page_attr -> change_page_attr_addr -> >>> __change_page_attr -> save_page -> list_add(&fpage->lru, &deferred_pages); >>> (2) free_page -> free_pages -> __free_pages -> free_hot_page -> >>> free_hot_cold_page -> list_add(&page->lru, &pcp->list); >> that'll hurt. >> >>> any ideas how to fix this? >> We should hold a single reference on the page for its membership in >> deferred_pages. > > The code is broken anyways. If you free pages without flushing > them first some other innocent user allocating them will end up > with possible uncached pages for some time. > > Does this simple patch help?
Yeah. (But X doesn't run -- this is maybe the known issue in this release).
> Flush uncached AGP pages before freeing > > Signed-off-by: Andi Kleen <ak@suse.de>
Tested-by: Jiri Slaby <jirislaby@gmail.com>
> > Index: linux/drivers/char/agp/generic.c > =================================================================== > --- linux.orig/drivers/char/agp/generic.c > +++ linux/drivers/char/agp/generic.c > @@ -1185,6 +1185,7 @@ void agp_generic_destroy_page(void *addr > > page = virt_to_page(addr); > unmap_page_from_agp(page); > + flush_agp_mappings(); > put_page(page); > free_page((unsigned long)addr); > atomic_dec(&agp_bridge->current_memory_agp); >
thanks, -- Jiri Slaby (jirislaby@gmail.com) Faculty of Informatics, Masaryk University - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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