Re: 2.6.24-rc1-54866f032307063776b4eff7eadb131d47f9f9b4 fails to boot: kernel BUG at include/linux/scatterlist.h:49!

[Jens Axboe <jens.axboe@oracle.com>]

On Sat, Nov 03 2007, Jens Axboe wrote:
> On Sat, Nov 03 2007, Stefan Richter wrote:
> > Torsten Kaiser wrote:
> > > On 11/2/07, Stefan Richter <stefanr@s5r6.in-berlin.de> wrote:
> > >> To which extent do you need IEEE 1394 drivers?
> > > 
> > > Using eth1394 as primary network connection on this computer.
> > > So switching to the new stack is currently not an option,
> > 
> > That's right.
> > 
> > > Looking that calltrace upwards, it seems replacing the
> > > memset(dma->sglist,...) with sg_init_table(...) would fix the BUG_ON()
> > > as that inits the SG_MAGIC.
> > 
> > Yes, this should be the first thing to be fixed.
> 
> It's probably enough. Only if you use chaining do you need to convert to
> using for_each_sg() and so on.

Did a grep over ieee1394/, this seems to be all you need.

diff --git a/drivers/ieee1394/dma.c b/drivers/ieee1394/dma.c
index f5f4983..7c4eb39 100644
--- a/drivers/ieee1394/dma.c
+++ b/drivers/ieee1394/dma.c
@@ -103,8 +103,7 @@ int dma_region_alloc(struct dma_region *dma, unsigned long n_bytes,
 		goto err;
 	}
 
-	/* just to be safe - this will become unnecessary once sglist->address goes away */
-	memset(dma->sglist, 0, dma->n_pages * sizeof(*dma->sglist));
+	sg_init_table(dma->sglist, dma->n_pages);
 
 	/* fill scatter/gather list with pages */
 	for (i = 0; i < dma->n_pages; i++) {

-- 
Jens Axboe