Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block

* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  cfq-iosched: cache prio_tree root in cfqq->p_root
  cfq-iosched: fix bug with aliased request and cooperation detection
  cfq-iosched: clear ->prio_trees[] on cfqd alloc
  block: fix intermittent dm timeout based oops
  umem: fix request_queue lock warning
  block: simplify I/O stat accounting
  pktcdvd.h should include mempool.h
  cfq-iosched: use the default seek distance when there aren't enough seek samples
  cfq-iosched: make seek_mean converge more quickly
  block: make blk_abort_queue() ignore non-request based devices
  block: include empty disks in /proc/diskstats
  bio: use bio_kmalloc() in copy/map functions
  bio: fix bio_kmalloc()
  block: fix queue bounce limit setting
  block: fix SG_IO vector request data length handling
  scatterlist: make sure sg_miter_next() doesn't return 0 sized mappings

1 files changed, 6 insertions, 3 deletions

diff --git a/lib/scatterlist.c b/lib/scatterlist.c
index b7b449dafbe5..a295e404e908 100644
--- a/lib/scatterlist.c
+++ b/lib/scatterlist.c
@@ -347,9 +347,12 @@ bool sg_miter_next(struct sg_mapping_iter *miter)
         sg_miter_stop(miter);
 
         /* get to the next sg if necessary.  __offset is adjusted by stop */
-        if (miter->__offset == miter->__sg->length && --miter->__nents) {
-                miter->__sg = sg_next(miter->__sg);
-                miter->__offset = 0;
+        while (miter->__offset == miter->__sg->length) {
+                if (--miter->__nents) {
+                        miter->__sg = sg_next(miter->__sg);
+                        miter->__offset = 0;
+                } else
+                        return false;
         }
 
         /* map the next page */