-stable review patch. If anyone has any objections, please let us know.
------------------
From: Badari Pulavarty <[email protected]>
Ran into BUG() while doing madvise(REMOVE) testing. If we are punching a
hole into shared memory segment using madvise(REMOVE) and the entire hole
is below the indirect blocks, we hit following assert.
BUG_ON(limit <= SHMEM_NR_DIRECT);
Signed-off-by: Badari Pulavarty <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Chris Wright <[email protected]>
---
mm/shmem.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
--- linux-2.6.19.1.orig/mm/shmem.c
+++ linux-2.6.19.1/mm/shmem.c
@@ -515,7 +515,12 @@ static void shmem_truncate_range(struct
size = SHMEM_NR_DIRECT;
nr_swaps_freed = shmem_free_swp(ptr+idx, ptr+size);
}
- if (!topdir)
+
+ /*
+ * If there are no indirect blocks or we are punching a hole
+ * below indirect blocks, nothing to be done.
+ */
+ if (!topdir || (punch_hole && (limit <= SHMEM_NR_DIRECT)))
goto done2;
BUG_ON(limit <= SHMEM_NR_DIRECT);
--