Messages in this thread | | | Date | Thu, 19 Mar 2015 15:09:01 -0700 | From | Andrew Morton <> | Subject | Re: [PATCH] lib/dma-debug: fix bucket_find_contain |
| |
On Mon, 16 Mar 2015 19:24:29 +0100 (CET) Sebastian Ott <sebott@linux.vnet.ibm.com> wrote:
> bucket_find_contain will search the bucket list for a dma_debug_entry. When > the entry isn't found it needs to search other buckets too, since only the > start address of a dma range is hashed (which might be in a different bucket). > > A copy of the dma_debug_entry is used to get the previous hash bucket but when > its list is searched the original dma_debug_entry is to be used not its > modified copy. > > This fixes false "device driver tries to sync DMA memory it has not allocated" > warnings.
The changelog doesn't help me understand how serious this is. A 4.0 thing? -stable?
> --- a/lib/dma-debug.c > +++ b/lib/dma-debug.c > @@ -361,7 +361,7 @@ static struct dma_debug_entry *bucket_fi > unsigned int range = 0; > > while (range <= max_range) { > - entry = __hash_bucket_find(*bucket, &index, containing_match); > + entry = __hash_bucket_find(*bucket, ref, containing_match); > > if (entry) > return entry;
This code just got more confusing :( Are you sure we aren't supposed to use `ref' in bucket_find_contain()'s call to get_hash_bucket()?
| |