On Thu, 2012-10-18 at 23:53 +0800, Ming Lei wrote: > Hi, > > Below v1 should be more efficient and simper, sorry for the noise. > > > Thanks, > -- > Ming Lei > > -- > From d275d195794ff80e018145f2fae714b35ddc49e2 Mon Sep 17 00:00:00 2001 > From: Ming Lei <[email protected]> > Date: Thu, 18 Oct 2012 23:30:57 +0800 > Subject: [PATCH v1] lib/dma-debug.c: fix __hash_bucket_find > > If there is only one match, the unique matched entry should be returned. > > Without the fix, the commit f62566214fe31c9f9b3218a42f1b19e6a9e6844a > > dma-debug: new interfaces to debug dma mapping errors > > can't work reliably because only device and dma_addr are passed to > dma_mapping_error(). > > Cc: Joerg Roedel <[email protected]> > Cc: Shuah Khan <[email protected]> > Cc: Paul Gortmaker <[email protected]> > Cc: Andrew Morton <[email protected]> > Cc: Jakub Kicinski <[email protected]> > Signed-off-by: Ming Lei <[email protected]> > --- > lib/dma-debug.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/lib/dma-debug.c b/lib/dma-debug.c > index 94aa94e..59f4a1a 100644 > --- a/lib/dma-debug.c > +++ b/lib/dma-debug.c > @@ -277,7 +277,7 @@ static struct dma_debug_entry > *__hash_bucket_find(struct hash_bucket *bucket, > match_fn match) > { > struct dma_debug_entry *entry, *ret = NULL; > - int matches = 0, match_lvl, last_lvl = 0; > + int matches = 0, match_lvl, last_lvl = -1; > > list_for_each_entry(entry, &bucket->list, list) { > if (!match(ref, entry)) > @@ -306,7 +306,7 @@ static struct dma_debug_entry > *__hash_bucket_find(struct hash_bucket *bucket, > } else if (match_lvl > last_lvl) { > /* > * We found an entry that fits better then the > - * previous one > + * previous one or it is the 1st match. > */ > last_lvl = match_lvl; > ret = entry;
Thanks for finding and fixing the problem. This fixes the problem Fengguang Wu reported: adding him to the thread. https://lkml.org/lkml/2012/10/14/233 I have a reliable test case and test system that reproduces the problem. Re-tested it with and without patch and didn't see the warning with your patch. That said, this patch is malformed and didn't apply cleanly. You have my Tested-by: Shuah Khan <[email protected]> Thanks, -- Shuah -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
