On Tue, 15 Jul 2008 10:37:58 -0400 (EDT) Mikulas Patocka <mpatocka@xxxxxxxxxx> wrote: > >>> This bug could happen on alpha, parisc, and sparc, which use VMERGE. > >> > >> Parisc doesn't use virtual merge accounting (there is variable for it but > >> it's always 0). > > > > Hmm, really? Looks like PARISC IOMMUs (ccio-dma.c and sba_iomm.c) set > > parisc_vmerge_boundary (CC'ed PARISC mailing list). > > That's right, I looked only at arch and include. > > >> On sparc64 it is broken anyway with or without your patch. > > > > Yeah, we need to modify SPARC64 IOMMU code (I'm not sure that it's > > worth). Right now, the best fix is setting BIO_VMERGE_BOUNDARY to 0. > > Even if we fix it now, the question is: how long it will stay fixed? Until > someone makes another change to struct device that restricts boundaries on > some wacky hardware. I'm not sure how the boundary restriction of a device can break the VMERGE accounting. -- To unsubscribe from this list: send the line "unsubscribe linux-parisc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
