diff --git a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_dataset.c b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_dataset.c
index 42d4704fdd18..dba47efedee9 100644
--- a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_dataset.c
+++ b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_dataset.c
@@ -4213,7 +4213,7 @@ zfs_get_fsacl(zfs_handle_t *zhp, nvlist_t **nvl)
 
 	(void) strlcpy(zc.zc_name, zhp->zfs_name, ZFS_MAXNAMELEN);
 
-	if (zfs_ioctl(hdl, ZFS_IOC_GET_FSACL, &zc) != 0) {
+	if (ioctl(hdl->libzfs_fd, ZFS_IOC_GET_FSACL, &zc) != 0) {
 		(void) snprintf(errbuf, sizeof (errbuf),
 		    dgettext(TEXT_DOMAIN, "cannot get permissions on '%s'"),
 		    zc.zc_name);
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c
index a0620b889347..3a289da6703d 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c
@@ -20,7 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2011 by Delphix. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  */
 
 #include <sys/zfs_context.h>
@@ -36,7 +36,7 @@
  * avoid having to load lots of space_maps in a given txg. There are,
  * however, some cases where we want to avoid "fast" ganging and instead
  * we want to do an exhaustive search of all metaslabs on this device.
- * Currently we don't allow any gang or dump device related allocations
+ * Currently we don't allow any gang, zil, or dump device related allocations
  * to "fast" gang.
  */
 #define	CAN_FASTGANG(flags) \
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa.c
index 8da471b3a3d2..f467223fd920 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa.c
@@ -1073,8 +1073,10 @@ spa_unload(spa_t *spa)
 	}
 	spa->spa_spares.sav_count = 0;
 
-	for (i = 0; i < spa->spa_l2cache.sav_count; i++)
+	for (i = 0; i < spa->spa_l2cache.sav_count; i++) {
+		vdev_clear_stats(spa->spa_l2cache.sav_vdevs[i]);
 		vdev_free(spa->spa_l2cache.sav_vdevs[i]);
+	}
 	if (spa->spa_l2cache.sav_vdevs) {
 		kmem_free(spa->spa_l2cache.sav_vdevs,
 		    spa->spa_l2cache.sav_count * sizeof (void *));
@@ -1302,11 +1304,13 @@ spa_load_l2cache(spa_t *spa)
 
 		vd = oldvdevs[i];
 		if (vd != NULL) {
+			ASSERT(vd->vdev_isl2cache);
+
 			if (spa_l2cache_exists(vd->vdev_guid, &pool) &&
 			    pool != 0ULL && l2arc_vdev_present(vd))
 				l2arc_remove_vdev(vd);
-			(void) vdev_close(vd);
-			spa_l2cache_remove(vd);
+			vdev_clear_stats(vd);
+			vdev_free(vd);
 		}
 	}
 
@@ -1949,7 +1953,7 @@ spa_load_impl(spa_t *spa, uint64_t pool_guid, nvlist_t *config,
 	 */
 	if (type != SPA_IMPORT_ASSEMBLE) {
 		spa_config_enter(spa, SCL_ALL, FTAG, RW_WRITER);
-		error = vdev_validate(rvd);
+		error = vdev_validate(rvd, mosconfig);
 		spa_config_exit(spa, SCL_ALL, FTAG);
 
 		if (error != 0)
@@ -2818,6 +2822,7 @@ spa_validate_aux_devs(spa_t *spa, nvlist_t *nvroot, uint64_t crtxg, int mode,
 		if ((strcmp(config, ZPOOL_CONFIG_L2CACHE) == 0) &&
 		    strcmp(vd->vdev_ops->vdev_op_type, VDEV_TYPE_DISK) != 0) {
 			error = ENOTBLK;
+			vdev_free(vd);
 			goto out;
 		}
 #endif
@@ -2927,10 +2932,6 @@ spa_l2cache_drop(spa_t *spa)
 		if (spa_l2cache_exists(vd->vdev_guid, &pool) &&
 		    pool != 0ULL && l2arc_vdev_present(vd))
 			l2arc_remove_vdev(vd);
-		if (vd->vdev_isl2cache)
-			spa_l2cache_remove(vd);
-		vdev_clear_stats(vd);
-		(void) vdev_close(vd);
 	}
 }
 
@@ -3929,7 +3930,7 @@ spa_vdev_attach(spa_t *spa, uint64_t guid, nvlist_t *nvroot, int replacing)
 	pvd = oldvd->vdev_parent;
 
 	if ((error = spa_config_parse(spa, &newrootvd, nvroot, NULL, 0,
-	    VDEV_ALLOC_ADD)) != 0)
+	    VDEV_ALLOC_ATTACH)) != 0)
 		return (spa_vdev_exit(spa, NULL, txg, EINVAL));
 
 	if (newrootvd->vdev_children != 1)
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/vdev.h b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/vdev.h
index 941f234dc68f..aa6559c801fe 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/vdev.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/vdev.h
@@ -20,6 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  */
 
 #ifndef _SYS_VDEV_H
@@ -48,7 +49,7 @@ extern boolean_t zfs_nocacheflush;
 extern int vdev_open(vdev_t *);
 extern void vdev_open_children(vdev_t *);
 extern boolean_t vdev_uses_zvols(vdev_t *);
-extern int vdev_validate(vdev_t *);
+extern int vdev_validate(vdev_t *, boolean_t);
 extern void vdev_close(vdev_t *);
 extern int vdev_create(vdev_t *, uint64_t txg, boolean_t isreplace);
 extern void vdev_reopen(vdev_t *);
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/vdev_impl.h b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/vdev_impl.h
index 7efa3f3b13cf..992ce0cf2760 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/vdev_impl.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/vdev_impl.h
@@ -261,6 +261,7 @@ typedef struct vdev_label {
 #define	VDEV_ALLOC_L2CACHE	3
 #define	VDEV_ALLOC_ROOTPOOL	4
 #define	VDEV_ALLOC_SPLIT	5
+#define	VDEV_ALLOC_ATTACH	6
 
 /*
  * Allocate or free a vdev
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev.c
index 04597ec2c6a6..b5d6fda56bc0 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/vdev.c
@@ -499,7 +499,7 @@ vdev_alloc(spa_t *spa, vdev_t **vdp, nvlist_t *nv, vdev_t *parent, uint_t id,
 		    &vd->vdev_removing);
 	}
 
-	if (parent && !parent->vdev_parent) {
+	if (parent && !parent->vdev_parent && alloctype != VDEV_ALLOC_ATTACH) {
 		ASSERT(alloctype == VDEV_ALLOC_LOAD ||
 		    alloctype == VDEV_ALLOC_ADD ||
 		    alloctype == VDEV_ALLOC_SPLIT ||
@@ -675,6 +675,8 @@ vdev_top_transfer(vdev_t *svd, vdev_t *tvd)
 	svd->vdev_ms_shift = 0;
 	svd->vdev_ms_count = 0;
 
+	if (tvd->vdev_mg)
+		ASSERT3P(tvd->vdev_mg, ==, svd->vdev_mg);
 	tvd->vdev_mg = svd->vdev_mg;
 	tvd->vdev_ms = svd->vdev_ms;
 
@@ -1294,13 +1296,18 @@ vdev_open(vdev_t *vd)
  * contents.  This needs to be done before vdev_load() so that we don't
  * inadvertently do repair I/Os to the wrong device.
  *
+ * If 'strict' is false ignore the spa guid check. This is necessary because
+ * if the machine crashed during a re-guid the new guid might have been written
+ * to all of the vdev labels, but not the cached config. The strict check
+ * will be performed when the pool is opened again using the mos config.
+ *
  * This function will only return failure if one of the vdevs indicates that it
  * has since been destroyed or exported.  This is only possible if
  * /etc/zfs/zpool.cache was readonly at the time.  Otherwise, the vdev state
  * will be updated but the function will return 0.
  */
 int
-vdev_validate(vdev_t *vd)
+vdev_validate(vdev_t *vd, boolean_t strict)
 {
 	spa_t *spa = vd->vdev_spa;
 	nvlist_t *label;
@@ -1308,7 +1315,7 @@ vdev_validate(vdev_t *vd)
 	uint64_t state;
 
 	for (int c = 0; c < vd->vdev_children; c++)
-		if (vdev_validate(vd->vdev_child[c]) != 0)
+		if (vdev_validate(vd->vdev_child[c], strict) != 0)
 			return (EBADF);
 
 	/*
@@ -1338,8 +1345,9 @@ vdev_validate(vdev_t *vd)
 			return (0);
 		}
 
-		if (nvlist_lookup_uint64(label, ZPOOL_CONFIG_POOL_GUID,
-		    &guid) != 0 || guid != spa_guid(spa)) {
+		if (strict && (nvlist_lookup_uint64(label,
+		    ZPOOL_CONFIG_POOL_GUID, &guid) != 0 ||
+		    guid != spa_guid(spa))) {
 			vdev_set_state(vd, B_FALSE, VDEV_STATE_CANT_OPEN,
 			    VDEV_AUX_CORRUPT_DATA);
 			nvlist_free(label);
@@ -1501,7 +1509,7 @@ vdev_reopen(vdev_t *vd)
 		    !l2arc_vdev_present(vd))
 			l2arc_add_vdev(spa, vd);
 	} else {
-		(void) vdev_validate(vd);
+		(void) vdev_validate(vd, B_TRUE);
 	}
 
 	/*
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_fm.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_fm.c
index 0b4812666442..fa5903a432dd 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_fm.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_fm.c
@@ -23,6 +23,10 @@
  * Use is subject to license terms.
  */
 
+/*
+ * Copyright (c) 2012 by Delphix. All rights reserved.
+ */
+
 #include <sys/spa.h>
 #include <sys/spa_impl.h>
 #include <sys/vdev.h>
@@ -709,6 +713,10 @@ zfs_ereport_start_checksum(spa_t *spa, vdev_t *vd,
 
 	if (report->zcr_ereport == NULL) {
 		report->zcr_free(report->zcr_cbdata, report->zcr_cbinfo);
+		if (report->zcr_ckinfo != NULL) {
+			kmem_free(report->zcr_ckinfo,
+			    sizeof (*report->zcr_ckinfo));
+		}
 		kmem_free(report, sizeof (*report));
 		return;
 	}
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zio.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zio.c
index 5f8f00b6a577..3eeeb58eedc8 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zio.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zio.c
@@ -20,7 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2011 by Delphix. All rights reserved.
+ * Copyright (c) 2012 by Delphix. All rights reserved.
  */
 
 #include <sys/zfs_context.h>
@@ -2235,13 +2235,22 @@ zio_alloc_zil(spa_t *spa, uint64_t txg, blkptr_t *new_bp, blkptr_t *old_bp,
 
 	ASSERT(txg > spa_syncing_txg(spa));
 
-	if (use_slog)
+	/*
+	 * ZIL blocks are always contiguous (i.e. not gang blocks) so we
+	 * set the METASLAB_GANG_AVOID flag so that they don't "fast gang"
+	 * when allocating them.
+	 */
+	if (use_slog) {
 		error = metaslab_alloc(spa, spa_log_class(spa), size,
-		    new_bp, 1, txg, old_bp, METASLAB_HINTBP_AVOID);
+		    new_bp, 1, txg, old_bp,
+		    METASLAB_HINTBP_AVOID | METASLAB_GANG_AVOID);
+	}
 
-	if (error)
+	if (error) {
 		error = metaslab_alloc(spa, spa_normal_class(spa), size,
-		    new_bp, 1, txg, old_bp, METASLAB_HINTBP_AVOID);
+		    new_bp, 1, txg, old_bp,
+		    METASLAB_HINTBP_AVOID | METASLAB_GANG_AVOID);
+	}
 
 	if (error == 0) {
 		BP_SET_LSIZE(new_bp, size);