By default a block driver bounces highmem requests, but virtio-blk is perfectly fine with any request that fit into it's 64 bit addressing scheme, mapped in the kernel virtual space or not. Besides improving performance on highmem systems this also makes the reproducible oops in __bounce_end_io go away (but hiding the real cause). Signed-off-by: Christoph Hellwig <hch@xxxxxx> Index: linux-2.6/drivers/block/virtio_blk.c =================================================================== --- linux-2.6.orig/drivers/block/virtio_blk.c 2009-06-15 16:28:24.225815322 +0200 +++ linux-2.6/drivers/block/virtio_blk.c 2009-06-19 18:03:12.469805377 +0200 @@ -360,6 +360,9 @@ static int __devinit virtblk_probe(struc blk_queue_max_phys_segments(vblk->disk->queue, vblk->sg_elems-2); blk_queue_max_hw_segments(vblk->disk->queue, vblk->sg_elems-2); + /* No need to bounce any requests */ + blk_queue_bounce_limit(brd->brd_queue, BLK_BOUNCE_ANY); + /* No real sector limit. */ blk_queue_max_sectors(vblk->disk->queue, -1U); -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
