Re: Hang: 2.6.32.4 sky2/DMAR (was [PATCH] sky2: Fix WARNING: atlib/dma-debug.c:902 check_sync)

From: Jarek Poplawski
Date: Thu Jan 28 2010 - 17:35:10 EST


On Thu, Jan 28, 2010 at 01:46:17PM -0500, Michael Breuer wrote:
> On 1/28/2010 12:08 PM, Stephen Hemminger wrote:
> >--- a/lib/dma-debug.c 2010-01-20 15:22:55.919519883 -0800
> >+++ b/lib/dma-debug.c 2010-01-20 15:26:31.648895638 -0800
> >@@ -285,11 +285,9 @@ static struct dma_debug_entry *hash_buck
> > }
> >
> > /*
> >- * If we have multiple matches but no perfect-fit, just return
> >- * NULL.
> >+ * If we have multiple matches but no perfect-fit
> >+ * return best value and let caller deal with it.
> > */
> >- ret = (matches == 1) ? ret : NULL;
> >-
> > return ret;
> > }
> >
> Ok - applied. Noise gone... however I'm not sure whether I'll be
> able to keep dma-debug going long enough to catch anything.
> num_free_entries keeps dropping... looks like entries are not freed.
> I'm running with a huge number for now & sky2 as the driver filter.
> Is there a reason that entries wouldn't be unmapped, or is
> dma-debug.c just not processing the unmap correctly?

Do you mean it's after this patch or earlier too? I think you might
use my sky2/receive_copy/pci_unmap_len patch instead to get rid of
this warning.

Btw, since 1000 was too much, maybe you could try copybreak=256 yet,
plus additional ping or some other source of shorter packets. And how
about trying this new switch?

Jarek P.
--
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/