Illumos #3522

3522 zfs module should not allow uninitialized variables
Reviewed by: Sebastien Roy <seb@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Garrett D'Amore <garrett@damore.org>

References:
  https://www.illumos.org/issues/3522
  illumos/illumos-gate@d5285cae913f4e01ffa0e6693a6d8ef1fbea30ba

Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>

Porting notes:

1. ZFSOnLinux had already addressed many of these issues because of
   its use of -Wall. However, the manner in which they were addressed
   differed. The illumos fixes replace the ones previously made in
   ZFSOnLinux to reduce code differences.

2. Part of the upstream patch made a small change to arc.c that might
   address zfsonlinux/zfs#1334.

3. The initialization of aclsize in zfs_log_create() differs because
   vsecp is a NULL pointer on ZFSOnLinux.

4. The changes to zfs_register_callbacks() were dropped because it
   has diverged and needs to be resynced.

1 files changed, 2 insertions, 1 deletions

diff --git a/module/zfs/spa.c b/module/zfs/spa.c
index 2bd011a0cbff..b400896c2969 100644
--- a/module/zfs/spa.c
+++ b/module/zfs/spa.c
@@ -1443,7 +1443,7 @@ spa_load_l2cache(spa_t *spa)
 	uint_t nl2cache;
 	int i, j, oldnvdevs;
 	uint64_t guid;
-	vdev_t *vd, **oldvdevs, **newvdevs = NULL;
+	vdev_t *vd, **oldvdevs, **newvdevs;
 	spa_aux_vdev_t *sav = &spa->spa_l2cache;
 
 	ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
@@ -1454,6 +1454,7 @@ spa_load_l2cache(spa_t *spa)
 		newvdevs = kmem_alloc(nl2cache * sizeof (void *), KM_PUSHPAGE);
 	} else {
 		nl2cache = 0;
+		newvdevs = NULL;
 	}
 
 	oldvdevs = sav->sav_vdevs;