gfs2: Fix "Introduce flag for glock holder auto-demotion"
Function demote_incompat_holders iterates over the list of glock holders
with list_for_each_entry, and it then sometimes removes the current
holder from the list. This will get the loop stuck; we must use
list_for_each_entry_safe instead.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 258d8aa..8dbd6fe 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -411,14 +411,14 @@ static void do_error(struct gfs2_glock *gl, const int ret)
static void demote_incompat_holders(struct gfs2_glock *gl,
struct gfs2_holder *new_gh)
{
- struct gfs2_holder *gh;
+ struct gfs2_holder *gh, *tmp;
/*
* Demote incompatible holders before we make ourselves eligible.
* (This holder may or may not allow auto-demoting, but we don't want
* to demote the new holder before it's even granted.)
*/
- list_for_each_entry(gh, &gl->gl_holders, gh_list) {
+ list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) {
/*
* Since holders are at the front of the list, we stop when we
* find the first non-holder.
