From: Mark Haverkamp <markh@osdl.org>
Last September a fix was checked in for a memory leak problem in
bounce_end_io causing the entire bio to be checked. This ended up causing
some dm cloned bios that had bounce buffers to free NULL pages because
their bi_idx can be non-zero. This patch skips NULL pages in the bio's
bio_vec. I'm not sure if this is the most optimal fix but I think that it
is safe since bvec_alloc memsets the bio_vec to zero.
Signed-off-by Mark Haverkamp <markh@osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/mm/highmem.c | 2 +-
1 files changed, 1 insertion(+), 1 deletion(-)
diff -puN mm/highmem.c~fix-panic-in-26-with-bounced-bio-and-dm mm/highmem.c
--- 25/mm/highmem.c~fix-panic-in-26-with-bounced-bio-and-dm Fri Feb 25 16:14:43 2005
+++ 25-akpm/mm/highmem.c Fri Feb 25 16:14:43 2005
@@ -319,7 +319,7 @@ static void bounce_end_io(struct bio *bi
*/
__bio_for_each_segment(bvec, bio, i, 0) {
org_vec = bio_orig->bi_io_vec + i;
- if (bvec->bv_page == org_vec->bv_page)
+ if (!bvec->bv_page || bvec->bv_page == org_vec->bv_page)
continue;
mempool_free(bvec->bv_page, pool);
_