diff --git a/cmd/ztest/ztest.c b/cmd/ztest/ztest.c
index 73694b0b35..a580396ebd 100644
--- a/cmd/ztest/ztest.c
+++ b/cmd/ztest/ztest.c
@@ -6669,7 +6669,7 @@ ztest_initialize(ztest_ds_t *zd, uint64_t id)
 	char *path = strdup(rand_vd->vdev_path);
 	boolean_t active = rand_vd->vdev_initialize_thread != NULL;
 
-	zfs_dbgmsg("vd %px, guid %llu", rand_vd, guid);
+	zfs_dbgmsg("vd %px, guid %llu", rand_vd, (u_longlong_t)guid);
 	spa_config_exit(spa, SCL_VDEV, FTAG);
 
 	uint64_t cmd = ztest_random(POOL_INITIALIZE_FUNCS);
@@ -6741,7 +6741,7 @@ ztest_trim(ztest_ds_t *zd, uint64_t id)
 	char *path = strdup(rand_vd->vdev_path);
 	boolean_t active = rand_vd->vdev_trim_thread != NULL;
 
-	zfs_dbgmsg("vd %p, guid %llu", rand_vd, guid);
+	zfs_dbgmsg("vd %p, guid %llu", rand_vd, (u_longlong_t)guid);
 	spa_config_exit(spa, SCL_VDEV, FTAG);
 
 	uint64_t cmd = ztest_random(POOL_TRIM_FUNCS);
diff --git a/include/sys/zfs_debug.h b/include/sys/zfs_debug.h
index 8b9629fb5e..7b103510dd 100644
--- a/include/sys/zfs_debug.h
+++ b/include/sys/zfs_debug.h
@@ -61,7 +61,7 @@ extern int zfs_dbgmsg_enable;
 extern void __set_error(const char *file, const char *func, int line, int err);
 extern void __zfs_dbgmsg(char *buf);
 extern void __dprintf(boolean_t dprint, const char *file, const char *func,
-    int line, const char *fmt, ...);
+    int line, const char *fmt, ...)  __attribute__((format(printf, 5, 6)));
 
 /*
  * Some general principles for using zfs_dbgmsg():
diff --git a/lib/libzpool/kernel.c b/lib/libzpool/kernel.c
index cc8e534e7e..09812decef 100644
--- a/lib/libzpool/kernel.c
+++ b/lib/libzpool/kernel.c
@@ -796,7 +796,7 @@ kernel_init(int mode)
 
 	physmem = sysconf(_SC_PHYS_PAGES);
 
-	dprintf("physmem = %llu pages (%.2f GB)\n", physmem,
+	dprintf("physmem = %llu pages (%.2f GB)\n", (u_longlong_t)physmem,
 	    (double)physmem * sysconf(_SC_PAGE_SIZE) / (1ULL << 30));
 
 	(void) snprintf(hw_serial, sizeof (hw_serial), "%ld",
diff --git a/module/os/freebsd/zfs/zfs_debug.c b/module/os/freebsd/zfs/zfs_debug.c
index 7239db8085..dad342b06f 100644
--- a/module/os/freebsd/zfs/zfs_debug.c
+++ b/module/os/freebsd/zfs/zfs_debug.c
@@ -181,7 +181,7 @@ __set_error(const char *file, const char *func, int line, int err)
 	 * $ echo 512 >/sys/module/zfs/parameters/zfs_flags
 	 */
 	if (zfs_flags & ZFS_DEBUG_SET_ERROR)
-		__dprintf(B_FALSE, file, func, line, "error %lu", err);
+		__dprintf(B_FALSE, file, func, line, "error %lu", (ulong_t)err);
 }
 
 #ifdef _KERNEL
diff --git a/module/os/freebsd/zfs/zfs_vfsops.c b/module/os/freebsd/zfs/zfs_vfsops.c
index 516d7dd81d..b05105e0bb 100644
--- a/module/os/freebsd/zfs/zfs_vfsops.c
+++ b/module/os/freebsd/zfs/zfs_vfsops.c
@@ -1066,7 +1066,7 @@ zfsvfs_setup(zfsvfs_t *zfsvfs, boolean_t mounting)
 				    &zfsvfs->z_kstat, zs.zs_num_entries);
 				dprintf_ds(zfsvfs->z_os->os_dsl_dataset,
 				    "num_entries in unlinked set: %llu",
-				    zs.zs_num_entries);
+				    (u_longlong_t)zs.zs_num_entries);
 			}
 
 			zfs_unlinked_drain(zfsvfs);
@@ -1880,7 +1880,9 @@ zfs_fhtovp(vfs_t *vfsp, fid_t *fidp, int flags, vnode_t **vpp)
 
 	gen_mask = -1ULL >> (64 - 8 * i);
 
-	dprintf("getting %llu [%u mask %llx]\n", object, fid_gen, gen_mask);
+	dprintf("getting %llu [%llu mask %llx]\n", (u_longlong_t)object,
+	    (u_longlong_t)fid_gen,
+	    (u_longlong_t)gen_mask);
 	if ((err = zfs_zget(zfsvfs, object, &zp))) {
 		ZFS_EXIT(zfsvfs);
 		return (err);
@@ -1891,7 +1893,8 @@ zfs_fhtovp(vfs_t *vfsp, fid_t *fidp, int flags, vnode_t **vpp)
 	if (zp_gen == 0)
 		zp_gen = 1;
 	if (zp->z_unlinked || zp_gen != fid_gen) {
-		dprintf("znode gen (%u) != fid gen (%u)\n", zp_gen, fid_gen);
+		dprintf("znode gen (%llu) != fid gen (%llu)\n",
+		    (u_longlong_t)zp_gen, (u_longlong_t)fid_gen);
 		vrele(ZTOV(zp));
 		ZFS_EXIT(zfsvfs);
 		return (SET_ERROR(EINVAL));
diff --git a/module/os/linux/zfs/zfs_debug.c b/module/os/linux/zfs/zfs_debug.c
index 8d7f04097d..98c9923d59 100644
--- a/module/os/linux/zfs/zfs_debug.c
+++ b/module/os/linux/zfs/zfs_debug.c
@@ -127,7 +127,8 @@ __set_error(const char *file, const char *func, int line, int err)
 	 * $ echo 512 >/sys/module/zfs/parameters/zfs_flags
 	 */
 	if (zfs_flags & ZFS_DEBUG_SET_ERROR)
-		__dprintf(B_FALSE, file, func, line, "error %lu", err);
+		__dprintf(B_FALSE, file, func, line, "error %lu",
+		    (ulong_t)err);
 }
 
 void
diff --git a/module/zfs/arc.c b/module/zfs/arc.c
index 43bfddff3e..7d892f4c7b 100644
--- a/module/zfs/arc.c
+++ b/module/zfs/arc.c
@@ -7184,8 +7184,11 @@ arc_tempreserve_space(spa_t *spa, uint64_t reserve, uint64_t txg)
 		    zfs_refcount_count(&arc_anon->arcs_esize[ARC_BUFC_DATA]);
 		dprintf("failing, arc_tempreserve=%lluK anon_meta=%lluK "
 		    "anon_data=%lluK tempreserve=%lluK rarc_c=%lluK\n",
-		    arc_tempreserve >> 10, meta_esize >> 10,
-		    data_esize >> 10, reserve >> 10, rarc_c >> 10);
+		    (u_longlong_t)arc_tempreserve >> 10,
+		    (u_longlong_t)meta_esize >> 10,
+		    (u_longlong_t)data_esize >> 10,
+		    (u_longlong_t)reserve >> 10,
+		    (u_longlong_t)rarc_c >> 10);
 #endif
 		DMU_TX_STAT_BUMP(dmu_tx_dirty_throttle);
 		return (SET_ERROR(ERESTART));
@@ -10255,7 +10258,7 @@ out:
 		 * log as the pool may be in the process of being removed.
 		 */
 		zfs_dbgmsg("L2ARC rebuild aborted, restored %llu blocks",
-		    zfs_refcount_count(&dev->l2ad_lb_count));
+		    (u_longlong_t)zfs_refcount_count(&dev->l2ad_lb_count));
 	} else if (err != 0) {
 		spa_history_log_internal(spa, "L2ARC rebuild", NULL,
 		    "aborted, restored %llu blocks",
@@ -10298,7 +10301,8 @@ l2arc_dev_hdr_read(l2arc_dev_t *dev)
 	if (err != 0) {
 		ARCSTAT_BUMP(arcstat_l2_rebuild_abort_dh_errors);
 		zfs_dbgmsg("L2ARC IO error (%d) while reading device header, "
-		    "vdev guid: %llu", err, dev->l2ad_vdev->vdev_guid);
+		    "vdev guid: %llu", err,
+		    (u_longlong_t)dev->l2ad_vdev->vdev_guid);
 		return (err);
 	}
 
@@ -10395,8 +10399,9 @@ l2arc_log_blk_read(l2arc_dev_t *dev,
 	if ((err = zio_wait(this_io)) != 0) {
 		ARCSTAT_BUMP(arcstat_l2_rebuild_abort_io_errors);
 		zfs_dbgmsg("L2ARC IO error (%d) while reading log block, "
-		    "offset: %llu, vdev guid: %llu", err, this_lbp->lbp_daddr,
-		    dev->l2ad_vdev->vdev_guid);
+		    "offset: %llu, vdev guid: %llu", err,
+		    (u_longlong_t)this_lbp->lbp_daddr,
+		    (u_longlong_t)dev->l2ad_vdev->vdev_guid);
 		goto cleanup;
 	}
 
@@ -10410,8 +10415,10 @@ l2arc_log_blk_read(l2arc_dev_t *dev,
 		ARCSTAT_BUMP(arcstat_l2_rebuild_abort_cksum_lb_errors);
 		zfs_dbgmsg("L2ARC log block cksum failed, offset: %llu, "
 		    "vdev guid: %llu, l2ad_hand: %llu, l2ad_evict: %llu",
-		    this_lbp->lbp_daddr, dev->l2ad_vdev->vdev_guid,
-		    dev->l2ad_hand, dev->l2ad_evict);
+		    (u_longlong_t)this_lbp->lbp_daddr,
+		    (u_longlong_t)dev->l2ad_vdev->vdev_guid,
+		    (u_longlong_t)dev->l2ad_hand,
+		    (u_longlong_t)dev->l2ad_evict);
 		err = SET_ERROR(ECKSUM);
 		goto cleanup;
 	}
@@ -10665,7 +10672,8 @@ l2arc_dev_hdr_update(l2arc_dev_t *dev)
 
 	if (err != 0) {
 		zfs_dbgmsg("L2ARC IO error (%d) while writing device header, "
-		    "vdev guid: %llu", err, dev->l2ad_vdev->vdev_guid);
+		    "vdev guid: %llu", err,
+		    (u_longlong_t)dev->l2ad_vdev->vdev_guid);
 	}
 }
 
diff --git a/module/zfs/dbuf.c b/module/zfs/dbuf.c
index 1eb0536f09..8e55a613bb 100644
--- a/module/zfs/dbuf.c
+++ b/module/zfs/dbuf.c
@@ -1850,7 +1850,8 @@ dbuf_free_range(dnode_t *dn, uint64_t start_blkid, uint64_t end_blkid,
 	if (end_blkid > dn->dn_maxblkid &&
 	    !(start_blkid == DMU_SPILL_BLKID || end_blkid == DMU_SPILL_BLKID))
 		end_blkid = dn->dn_maxblkid;
-	dprintf_dnode(dn, "start=%llu end=%llu\n", start_blkid, end_blkid);
+	dprintf_dnode(dn, "start=%llu end=%llu\n", (u_longlong_t)start_blkid,
+	    (u_longlong_t)end_blkid);
 
 	db_search = kmem_alloc(sizeof (dmu_buf_impl_t), KM_SLEEP);
 	db_search->db_level = 0;
diff --git a/module/zfs/dmu_objset.c b/module/zfs/dmu_objset.c
index 8c244dc4c3..22deee7f3d 100644
--- a/module/zfs/dmu_objset.c
+++ b/module/zfs/dmu_objset.c
@@ -1616,7 +1616,7 @@ dmu_objset_sync(objset_t *os, zio_t *pio, dmu_tx_t *tx)
 	blkptr_t *blkptr_copy = kmem_alloc(sizeof (*os->os_rootbp), KM_SLEEP);
 	*blkptr_copy = *os->os_rootbp;
 
-	dprintf_ds(os->os_dsl_dataset, "txg=%llu\n", tx->tx_txg);
+	dprintf_ds(os->os_dsl_dataset, "txg=%llu\n", (u_longlong_t)tx->tx_txg);
 
 	ASSERT(dmu_tx_is_syncing(tx));
 	/* XXX the write_done callback should really give us the tx... */
diff --git a/module/zfs/dmu_recv.c b/module/zfs/dmu_recv.c
index a713e13290..0ec46bdb4f 100644
--- a/module/zfs/dmu_recv.c
+++ b/module/zfs/dmu_recv.c
@@ -2588,8 +2588,8 @@ dprintf_drr(struct receive_record_arg *rrd, int err)
 		dprintf("drr_type = OBJECT obj = %llu type = %u "
 		    "bonustype = %u blksz = %u bonuslen = %u cksumtype = %u "
 		    "compress = %u dn_slots = %u err = %d\n",
-		    drro->drr_object, drro->drr_type,  drro->drr_bonustype,
-		    drro->drr_blksz, drro->drr_bonuslen,
+		    (u_longlong_t)drro->drr_object, drro->drr_type,
+		    drro->drr_bonustype, drro->drr_blksz, drro->drr_bonuslen,
 		    drro->drr_checksumtype, drro->drr_compress,
 		    drro->drr_dn_slots, err);
 		break;
@@ -2600,7 +2600,8 @@ dprintf_drr(struct receive_record_arg *rrd, int err)
 		    &rrd->header.drr_u.drr_freeobjects;
 		dprintf("drr_type = FREEOBJECTS firstobj = %llu "
 		    "numobjs = %llu err = %d\n",
-		    drrfo->drr_firstobj, drrfo->drr_numobjs, err);
+		    (u_longlong_t)drrfo->drr_firstobj,
+		    (u_longlong_t)drrfo->drr_numobjs, err);
 		break;
 	}
 	case DRR_WRITE:
@@ -2609,10 +2610,12 @@ dprintf_drr(struct receive_record_arg *rrd, int err)
 		dprintf("drr_type = WRITE obj = %llu type = %u offset = %llu "
 		    "lsize = %llu cksumtype = %u flags = %u "
 		    "compress = %u psize = %llu err = %d\n",
-		    drrw->drr_object, drrw->drr_type, drrw->drr_offset,
-		    drrw->drr_logical_size, drrw->drr_checksumtype,
-		    drrw->drr_flags, drrw->drr_compressiontype,
-		    drrw->drr_compressed_size, err);
+		    (u_longlong_t)drrw->drr_object, drrw->drr_type,
+		    (u_longlong_t)drrw->drr_offset,
+		    (u_longlong_t)drrw->drr_logical_size,
+		    drrw->drr_checksumtype, drrw->drr_flags,
+		    drrw->drr_compressiontype,
+		    (u_longlong_t)drrw->drr_compressed_size, err);
 		break;
 	}
 	case DRR_WRITE_BYREF:
@@ -2623,11 +2626,14 @@ dprintf_drr(struct receive_record_arg *rrd, int err)
 		    "length = %llu toguid = %llx refguid = %llx "
 		    "refobject = %llu refoffset = %llu cksumtype = %u "
 		    "flags = %u err = %d\n",
-		    drrwbr->drr_object, drrwbr->drr_offset,
-		    drrwbr->drr_length, drrwbr->drr_toguid,
-		    drrwbr->drr_refguid, drrwbr->drr_refobject,
-		    drrwbr->drr_refoffset, drrwbr->drr_checksumtype,
-		    drrwbr->drr_flags, err);
+		    (u_longlong_t)drrwbr->drr_object,
+		    (u_longlong_t)drrwbr->drr_offset,
+		    (u_longlong_t)drrwbr->drr_length,
+		    (u_longlong_t)drrwbr->drr_toguid,
+		    (u_longlong_t)drrwbr->drr_refguid,
+		    (u_longlong_t)drrwbr->drr_refobject,
+		    (u_longlong_t)drrwbr->drr_refoffset,
+		    drrwbr->drr_checksumtype, drrwbr->drr_flags, err);
 		break;
 	}
 	case DRR_WRITE_EMBEDDED:
@@ -2637,7 +2643,9 @@ dprintf_drr(struct receive_record_arg *rrd, int err)
 		dprintf("drr_type = WRITE_EMBEDDED obj = %llu offset = %llu "
 		    "length = %llu compress = %u etype = %u lsize = %u "
 		    "psize = %u err = %d\n",
-		    drrwe->drr_object, drrwe->drr_offset, drrwe->drr_length,
+		    (u_longlong_t)drrwe->drr_object,
+		    (u_longlong_t)drrwe->drr_offset,
+		    (u_longlong_t)drrwe->drr_length,
 		    drrwe->drr_compression, drrwe->drr_etype,
 		    drrwe->drr_lsize, drrwe->drr_psize, err);
 		break;
@@ -2647,7 +2655,9 @@ dprintf_drr(struct receive_record_arg *rrd, int err)
 		struct drr_free *drrf = &rrd->header.drr_u.drr_free;
 		dprintf("drr_type = FREE obj = %llu offset = %llu "
 		    "length = %lld err = %d\n",
-		    drrf->drr_object, drrf->drr_offset, drrf->drr_length,
+		    (u_longlong_t)drrf->drr_object,
+		    (u_longlong_t)drrf->drr_offset,
+		    (longlong_t)drrf->drr_length,
 		    err);
 		break;
 	}
@@ -2655,7 +2665,8 @@ dprintf_drr(struct receive_record_arg *rrd, int err)
 	{
 		struct drr_spill *drrs = &rrd->header.drr_u.drr_spill;
 		dprintf("drr_type = SPILL obj = %llu length = %llu "
-		    "err = %d\n", drrs->drr_object, drrs->drr_length, err);
+		    "err = %d\n", (u_longlong_t)drrs->drr_object,
+		    (u_longlong_t)drrs->drr_length, err);
 		break;
 	}
 	case DRR_OBJECT_RANGE:
@@ -2664,7 +2675,8 @@ dprintf_drr(struct receive_record_arg *rrd, int err)
 		    &rrd->header.drr_u.drr_object_range;
 		dprintf("drr_type = OBJECT_RANGE firstobj = %llu "
 		    "numslots = %llu flags = %u err = %d\n",
-		    drror->drr_firstobj, drror->drr_numslots,
+		    (u_longlong_t)drror->drr_firstobj,
+		    (u_longlong_t)drror->drr_numslots,
 		    drror->drr_flags, err);
 		break;
 	}
diff --git a/module/zfs/dmu_tx.c b/module/zfs/dmu_tx.c
index 73667915df..0beb983f99 100644
--- a/module/zfs/dmu_tx.c
+++ b/module/zfs/dmu_tx.c
@@ -613,7 +613,8 @@ dmu_tx_dirty_buf(dmu_tx_t *tx, dmu_buf_impl_t *db)
 			/* XXX txh_arg2 better not be zero... */
 
 			dprintf("found txh type %x beginblk=%llx endblk=%llx\n",
-			    txh->txh_type, beginblk, endblk);
+			    txh->txh_type, (u_longlong_t)beginblk,
+			    (u_longlong_t)endblk);
 
 			switch (txh->txh_type) {
 			case THT_WRITE:
diff --git a/module/zfs/dnode.c b/module/zfs/dnode.c
index 8434e72aa4..b1813a8951 100644
--- a/module/zfs/dnode.c
+++ b/module/zfs/dnode.c
@@ -592,7 +592,8 @@ dnode_allocate(dnode_t *dn, dmu_object_type_t ot, int blocksize, int ibs,
 	ibs = MIN(MAX(ibs, DN_MIN_INDBLKSHIFT), DN_MAX_INDBLKSHIFT);
 
 	dprintf("os=%p obj=%llu txg=%llu blocksize=%d ibs=%d dn_slots=%d\n",
-	    dn->dn_objset, dn->dn_object, tx->tx_txg, blocksize, ibs, dn_slots);
+	    dn->dn_objset, (u_longlong_t)dn->dn_object,
+	    (u_longlong_t)tx->tx_txg, blocksize, ibs, dn_slots);
 	DNODE_STAT_BUMP(dnode_allocate);
 
 	ASSERT(dn->dn_type == DMU_OT_NONE);
@@ -1690,7 +1691,7 @@ dnode_setdirty(dnode_t *dn, dmu_tx_t *tx)
 	ASSERT0(dn->dn_next_bonustype[txg & TXG_MASK]);
 
 	dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n",
-	    dn->dn_object, txg);
+	    (u_longlong_t)dn->dn_object, (u_longlong_t)txg);
 
 	multilist_sublist_insert_head(mls, dn);
 
@@ -2253,7 +2254,8 @@ done:
 		range_tree_add(dn->dn_free_ranges[txgoff], blkid, nblks);
 	}
 	dprintf_dnode(dn, "blkid=%llu nblks=%llu txg=%llu\n",
-	    blkid, nblks, tx->tx_txg);
+	    (u_longlong_t)blkid, (u_longlong_t)nblks,
+	    (u_longlong_t)tx->tx_txg);
 	mutex_exit(&dn->dn_mtx);
 
 	dbuf_free_range(dn, blkid, blkid + nblks - 1, tx);
diff --git a/module/zfs/dnode_sync.c b/module/zfs/dnode_sync.c
index 66e48a1e17..dd37e3af7e 100644
--- a/module/zfs/dnode_sync.c
+++ b/module/zfs/dnode_sync.c
@@ -59,7 +59,7 @@ dnode_increase_indirection(dnode_t *dn, dmu_tx_t *tx)
 
 	dn->dn_phys->dn_nlevels = new_level;
 	dprintf("os=%p obj=%llu, increase to %d\n", dn->dn_objset,
-	    dn->dn_object, dn->dn_phys->dn_nlevels);
+	    (u_longlong_t)dn->dn_object, dn->dn_phys->dn_nlevels);
 
 	/*
 	 * Lock ordering requires that we hold the children's db_mutexes (by
@@ -136,7 +136,8 @@ free_blocks(dnode_t *dn, blkptr_t *bp, int num, dmu_tx_t *tx)
 	dsl_dataset_t *ds = dn->dn_objset->os_dsl_dataset;
 	uint64_t bytesfreed = 0;
 
-	dprintf("ds=%p obj=%llx num=%d\n", ds, dn->dn_object, num);
+	dprintf("ds=%p obj=%llx num=%d\n", ds, (u_longlong_t)dn->dn_object,
+	    num);
 
 	for (int i = 0; i < num; i++, bp++) {
 		if (BP_IS_HOLE(bp))
diff --git a/module/zfs/dsl_dataset.c b/module/zfs/dsl_dataset.c
index 9b9bb42287..1c03216ef6 100644
--- a/module/zfs/dsl_dataset.c
+++ b/module/zfs/dsl_dataset.c
@@ -282,7 +282,7 @@ dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx,
 	if (bp->blk_birth > dsl_dataset_phys(ds)->ds_prev_snap_txg) {
 		int64_t delta;
 
-		dprintf_bp(bp, "freeing ds=%llu", ds->ds_object);
+		dprintf_bp(bp, "freeing ds=%llu", (u_longlong_t)ds->ds_object);
 		dsl_free(tx->tx_pool, tx->tx_txg, bp);
 
 		mutex_enter(&ds->ds_lock);
@@ -721,7 +721,7 @@ dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag,
 				    dsl_dataset_phys(ds)->ds_fsid_guid,
 				    (long long)ds->ds_fsid_guid,
 				    spa_name(dp->dp_spa),
-				    dsobj);
+				    (u_longlong_t)dsobj);
 			}
 		}
 	}
diff --git a/module/zfs/dsl_destroy.c b/module/zfs/dsl_destroy.c
index 837d78987e..a2748197f2 100644
--- a/module/zfs/dsl_destroy.c
+++ b/module/zfs/dsl_destroy.c
@@ -654,7 +654,7 @@ dsl_destroy_snapshots_nvl(nvlist_t *snaps, boolean_t defer,
 		char *errorstr = NULL;
 		(void) nvlist_lookup_string(result, ZCP_RET_ERROR, &errorstr);
 		if (errorstr != NULL) {
-			zfs_dbgmsg(errorstr);
+			zfs_dbgmsg("%s", errorstr);
 		}
 		fnvlist_free(wrapper);
 		fnvlist_free(result);
diff --git a/module/zfs/dsl_dir.c b/module/zfs/dsl_dir.c
index 90dd787023..df2c3d8f06 100644
--- a/module/zfs/dsl_dir.c
+++ b/module/zfs/dsl_dir.c
@@ -488,7 +488,7 @@ dsl_dir_hold(dsl_pool_t *dp, const char *name, void *tag,
 		if (next[0] == '@')
 			break;
 		dprintf("looking up %s in obj%lld\n",
-		    buf, dsl_dir_phys(dd)->dd_child_dir_zapobj);
+		    buf, (longlong_t)dsl_dir_phys(dd)->dd_child_dir_zapobj);
 
 		err = zap_lookup(dp->dp_meta_objset,
 		    dsl_dir_phys(dd)->dd_child_dir_zapobj,
@@ -1156,8 +1156,8 @@ dsl_dir_sync(dsl_dir_t *dd, dmu_tx_t *tx)
 
 	mutex_enter(&dd->dd_lock);
 	ASSERT0(dd->dd_tempreserved[tx->tx_txg & TXG_MASK]);
-	dprintf_dd(dd, "txg=%llu towrite=%lluK\n", tx->tx_txg,
-	    dd->dd_space_towrite[tx->tx_txg & TXG_MASK] / 1024);
+	dprintf_dd(dd, "txg=%llu towrite=%lluK\n", (u_longlong_t)tx->tx_txg,
+	    (u_longlong_t)dd->dd_space_towrite[tx->tx_txg & TXG_MASK] / 1024);
 	dd->dd_space_towrite[tx->tx_txg & TXG_MASK] = 0;
 	mutex_exit(&dd->dd_lock);
 
@@ -1344,8 +1344,9 @@ top_of_function:
 			retval = ERESTART;
 		dprintf_dd(dd, "failing: used=%lluK inflight = %lluK "
 		    "quota=%lluK tr=%lluK err=%d\n",
-		    used_on_disk>>10, est_inflight>>10,
-		    quota>>10, asize>>10, retval);
+		    (u_longlong_t)used_on_disk>>10,
+		    (u_longlong_t)est_inflight>>10,
+		    (u_longlong_t)quota>>10, (u_longlong_t)asize>>10, retval);
 		mutex_exit(&dd->dd_lock);
 		DMU_TX_STAT_BUMP(dmu_tx_quota);
 		return (SET_ERROR(retval));
diff --git a/module/zfs/metaslab.c b/module/zfs/metaslab.c
index e588765b33..21914c1aee 100644
--- a/module/zfs/metaslab.c
+++ b/module/zfs/metaslab.c
@@ -2437,18 +2437,20 @@ metaslab_load_impl(metaslab_t *msp)
 	    "loading_time %lld ms, ms_max_size %llu, "
 	    "max size error %lld, "
 	    "old_weight %llx, new_weight %llx",
-	    spa_syncing_txg(spa), spa_name(spa),
-	    msp->ms_group->mg_vd->vdev_id, msp->ms_id,
-	    space_map_length(msp->ms_sm),
-	    range_tree_space(msp->ms_unflushed_allocs),
-	    range_tree_space(msp->ms_unflushed_frees),
-	    range_tree_space(msp->ms_freed),
-	    range_tree_space(msp->ms_defer[0]),
-	    range_tree_space(msp->ms_defer[1]),
+	    (u_longlong_t)spa_syncing_txg(spa), spa_name(spa),
+	    (u_longlong_t)msp->ms_group->mg_vd->vdev_id,
+	    (u_longlong_t)msp->ms_id,
+	    (u_longlong_t)space_map_length(msp->ms_sm),
+	    (u_longlong_t)range_tree_space(msp->ms_unflushed_allocs),
+	    (u_longlong_t)range_tree_space(msp->ms_unflushed_frees),
+	    (u_longlong_t)range_tree_space(msp->ms_freed),
+	    (u_longlong_t)range_tree_space(msp->ms_defer[0]),
+	    (u_longlong_t)range_tree_space(msp->ms_defer[1]),
 	    (longlong_t)((load_start - msp->ms_unload_time) / 1000000),
 	    (longlong_t)((load_end - load_start) / 1000000),
-	    msp->ms_max_size, msp->ms_max_size - max_size,
-	    weight, msp->ms_weight);
+	    (u_longlong_t)msp->ms_max_size,
+	    (u_longlong_t)msp->ms_max_size - max_size,
+	    (u_longlong_t)weight, (u_longlong_t)msp->ms_weight);
 
 	metaslab_verify_space(msp, spa_syncing_txg(spa));
 	mutex_exit(&msp->ms_sync_lock);
@@ -2545,14 +2547,17 @@ metaslab_unload(metaslab_t *msp)
 		    "ms_id %llu, weight %llx, "
 		    "selected txg %llu (%llu ms ago), alloc_txg %llu, "
 		    "loaded %llu ms ago, max_size %llu",
-		    spa_syncing_txg(spa), spa_name(spa),
-		    msp->ms_group->mg_vd->vdev_id, msp->ms_id,
-		    msp->ms_weight,
-		    msp->ms_selected_txg,
-		    (msp->ms_unload_time - msp->ms_selected_time) / 1000 / 1000,
-		    msp->ms_alloc_txg,
-		    (msp->ms_unload_time - msp->ms_load_time) / 1000 / 1000,
-		    msp->ms_max_size);
+		    (u_longlong_t)spa_syncing_txg(spa), spa_name(spa),
+		    (u_longlong_t)msp->ms_group->mg_vd->vdev_id,
+		    (u_longlong_t)msp->ms_id,
+		    (u_longlong_t)msp->ms_weight,
+		    (u_longlong_t)msp->ms_selected_txg,
+		    (u_longlong_t)(msp->ms_unload_time -
+		    msp->ms_selected_time) / 1000 / 1000,
+		    (u_longlong_t)msp->ms_alloc_txg,
+		    (u_longlong_t)(msp->ms_unload_time -
+		    msp->ms_load_time) / 1000 / 1000,
+		    (u_longlong_t)msp->ms_max_size);
 	}
 
 	/*
@@ -2914,8 +2919,9 @@ metaslab_set_fragmentation(metaslab_t *msp, boolean_t nodirty)
 			msp->ms_condense_wanted = B_TRUE;
 			vdev_dirty(vd, VDD_METASLAB, msp, txg + 1);
 			zfs_dbgmsg("txg %llu, requesting force condense: "
-			    "ms_id %llu, vdev_id %llu", txg, msp->ms_id,
-			    vd->vdev_id);
+			    "ms_id %llu, vdev_id %llu", (u_longlong_t)txg,
+			    (u_longlong_t)msp->ms_id,
+			    (u_longlong_t)vd->vdev_id);
 		}
 		msp->ms_fragmentation = ZFS_FRAG_INVALID;
 		return;
@@ -3635,10 +3641,11 @@ metaslab_condense(metaslab_t *msp, dmu_tx_t *tx)
 	ASSERT(range_tree_is_empty(msp->ms_freed)); /* since it is pass 1 */
 
 	zfs_dbgmsg("condensing: txg %llu, msp[%llu] %px, vdev id %llu, "
-	    "spa %s, smp size %llu, segments %lu, forcing condense=%s", txg,
-	    msp->ms_id, msp, msp->ms_group->mg_vd->vdev_id,
-	    spa->spa_name, space_map_length(msp->ms_sm),
-	    range_tree_numsegs(msp->ms_allocatable),
+	    "spa %s, smp size %llu, segments %llu, forcing condense=%s",
+	    (u_longlong_t)txg, (u_longlong_t)msp->ms_id, msp,
+	    (u_longlong_t)msp->ms_group->mg_vd->vdev_id,
+	    spa->spa_name, (u_longlong_t)space_map_length(msp->ms_sm),
+	    (u_longlong_t)range_tree_numsegs(msp->ms_allocatable),
 	    msp->ms_condense_wanted ? "TRUE" : "FALSE");
 
 	msp->ms_condense_wanted = B_FALSE;
@@ -3883,11 +3890,13 @@ metaslab_flush(metaslab_t *msp, dmu_tx_t *tx)
 	if (zfs_flags & ZFS_DEBUG_LOG_SPACEMAP) {
 		zfs_dbgmsg("flushing: txg %llu, spa %s, vdev_id %llu, "
 		    "ms_id %llu, unflushed_allocs %llu, unflushed_frees %llu, "
-		    "appended %llu bytes", dmu_tx_get_txg(tx), spa_name(spa),
-		    msp->ms_group->mg_vd->vdev_id, msp->ms_id,
-		    range_tree_space(msp->ms_unflushed_allocs),
-		    range_tree_space(msp->ms_unflushed_frees),
-		    (sm_len_after - sm_len_before));
+		    "appended %llu bytes", (u_longlong_t)dmu_tx_get_txg(tx),
+		    spa_name(spa),
+		    (u_longlong_t)msp->ms_group->mg_vd->vdev_id,
+		    (u_longlong_t)msp->ms_id,
+		    (u_longlong_t)range_tree_space(msp->ms_unflushed_allocs),
+		    (u_longlong_t)range_tree_space(msp->ms_unflushed_frees),
+		    (u_longlong_t)(sm_len_after - sm_len_before));
 	}
 
 	ASSERT3U(spa->spa_unflushed_stats.sus_memused, >=,
diff --git a/module/zfs/mmp.c b/module/zfs/mmp.c
index d05c9db24c..d9ed457a71 100644
--- a/module/zfs/mmp.c
+++ b/module/zfs/mmp.c
@@ -485,8 +485,9 @@ mmp_write_uberblock(spa_t *spa)
 	if (mmp->mmp_skip_error != 0) {
 		mmp->mmp_skip_error = 0;
 		zfs_dbgmsg("MMP write after skipping due to unavailable "
-		    "leaves, pool '%s' gethrtime %llu leaf %#llu",
-		    spa_name(spa), gethrtime(), vd->vdev_guid);
+		    "leaves, pool '%s' gethrtime %llu leaf %llu",
+		    spa_name(spa), (u_longlong_t)gethrtime(),
+		    (u_longlong_t)vd->vdev_guid);
 	}
 
 	if (mmp->mmp_zio_root == NULL)
@@ -617,10 +618,11 @@ mmp_thread(void *arg)
 			    "mmp_interval %llu last_mmp_fail_intervals %u "
 			    "mmp_fail_intervals %u mmp_fail_ns %llu "
 			    "skip_wait %d leaves %d next_time %llu",
-			    spa_name(spa), gethrtime(), last_mmp_interval,
-			    mmp_interval, last_mmp_fail_intervals,
-			    mmp_fail_intervals, mmp_fail_ns, skip_wait, leaves,
-			    next_time);
+			    spa_name(spa), (u_longlong_t)gethrtime(),
+			    (u_longlong_t)last_mmp_interval,
+			    (u_longlong_t)mmp_interval, last_mmp_fail_intervals,
+			    mmp_fail_intervals, (u_longlong_t)mmp_fail_ns,
+			    skip_wait, leaves, (u_longlong_t)next_time);
 		}
 
 		/*
@@ -633,8 +635,9 @@ mmp_thread(void *arg)
 			zfs_dbgmsg("MMP state change pool '%s': gethrtime %llu "
 			    "last_spa_multihost %u multihost %u "
 			    "last_spa_suspended %u suspended %u",
-			    spa_name(spa), last_spa_multihost, multihost,
-			    last_spa_suspended, suspended);
+			    spa_name(spa), (u_longlong_t)gethrtime(),
+			    last_spa_multihost, multihost, last_spa_suspended,
+			    suspended);
 			mutex_enter(&mmp->mmp_io_lock);
 			mmp->mmp_last_write = gethrtime();
 			mmp->mmp_delay = mmp_interval;
diff --git a/module/zfs/range_tree.c b/module/zfs/range_tree.c
index 5219fd079b..595918e5a7 100644
--- a/module/zfs/range_tree.c
+++ b/module/zfs/range_tree.c
@@ -116,7 +116,8 @@ range_tree_stat_verify(range_tree_t *rt)
 	for (i = 0; i < RANGE_TREE_HISTOGRAM_SIZE; i++) {
 		if (hist[i] != rt->rt_histogram[i]) {
 			zfs_dbgmsg("i=%d, hist=%px, hist=%llu, rt_hist=%llu",
-			    i, hist, hist[i], rt->rt_histogram[i]);
+			    i, hist, (u_longlong_t)hist[i],
+			    (u_longlong_t)rt->rt_histogram[i]);
 		}
 		VERIFY3U(hist[i], ==, rt->rt_histogram[i]);
 	}
diff --git a/module/zfs/sa.c b/module/zfs/sa.c
index 5af0aaa7d0..2604a7513e 100644
--- a/module/zfs/sa.c
+++ b/module/zfs/sa.c
@@ -1292,7 +1292,7 @@ sa_build_index(sa_handle_t *hdl, sa_buf_type_t buftype)
 			mutex_exit(&sa->sa_lock);
 			zfs_dbgmsg("Buffer Header: %x != SA_MAGIC:%x "
 			    "object=%#llx\n", sa_hdr_phys->sa_magic, SA_MAGIC,
-			    db->db.db_object);
+			    (u_longlong_t)db->db.db_object);
 			return (SET_ERROR(EIO));
 		}
 		sa_byteswap(hdl, buftype);
diff --git a/module/zfs/spa.c b/module/zfs/spa.c
index 26995575ad..e029d00587 100644
--- a/module/zfs/spa.c
+++ b/module/zfs/spa.c
@@ -2578,8 +2578,9 @@ spa_livelist_delete_cb(void *arg, zthr_t *z)
 			    .to_free = &to_free
 			};
 			zfs_dbgmsg("deleting sublist (id %llu) from"
-			    " livelist %llu, %d remaining",
-			    dle->dle_bpobj.bpo_object, ll_obj, count - 1);
+			    " livelist %llu, %lld remaining",
+			    (u_longlong_t)dle->dle_bpobj.bpo_object,
+			    (u_longlong_t)ll_obj, (longlong_t)count - 1);
 			VERIFY0(dsl_sync_task(spa_name(spa), NULL,
 			    sublist_delete_sync, &sync_arg, 0,
 			    ZFS_SPACE_CHECK_DESTROY));
@@ -2596,7 +2597,8 @@ spa_livelist_delete_cb(void *arg, zthr_t *z)
 		    .ll_obj = ll_obj,
 		    .zap_obj = zap_obj
 		};
-		zfs_dbgmsg("deletion of livelist %llu completed", ll_obj);
+		zfs_dbgmsg("deletion of livelist %llu completed",
+		    (u_longlong_t)ll_obj);
 		VERIFY0(dsl_sync_task(spa_name(spa), NULL, livelist_delete_sync,
 		    &sync_arg, 0, ZFS_SPACE_CHECK_DESTROY));
 	}
@@ -2696,10 +2698,12 @@ spa_livelist_condense_sync(void *arg, dmu_tx_t *tx)
 	dsl_dataset_name(ds, dsname);
 	zfs_dbgmsg("txg %llu condensing livelist of %s (id %llu), bpobj %llu "
 	    "(%llu blkptrs) and bpobj %llu (%llu blkptrs) -> bpobj %llu "
-	    "(%llu blkptrs)", tx->tx_txg, dsname, ds->ds_object, first_obj,
-	    cur_first_size, next_obj, cur_next_size,
-	    first->dle_bpobj.bpo_object,
-	    first->dle_bpobj.bpo_phys->bpo_num_blkptrs);
+	    "(%llu blkptrs)", (u_longlong_t)tx->tx_txg, dsname,
+	    (u_longlong_t)ds->ds_object, (u_longlong_t)first_obj,
+	    (u_longlong_t)cur_first_size, (u_longlong_t)next_obj,
+	    (u_longlong_t)cur_next_size,
+	    (u_longlong_t)first->dle_bpobj.bpo_object,
+	    (u_longlong_t)first->dle_bpobj.bpo_phys->bpo_num_blkptrs);
 out:
 	dmu_buf_rele(ds->ds_dbuf, spa);
 	spa->spa_to_condense.ds = NULL;
@@ -3091,8 +3095,10 @@ spa_activity_check_duration(spa_t *spa, uberblock_t *ub)
 
 		zfs_dbgmsg("fail_intvals>0 import_delay=%llu ub_mmp "
 		    "mmp_fails=%llu ub_mmp mmp_interval=%llu "
-		    "import_intervals=%u", import_delay, MMP_FAIL_INT(ub),
-		    MMP_INTERVAL(ub), import_intervals);
+		    "import_intervals=%llu", (u_longlong_t)import_delay,
+		    (u_longlong_t)MMP_FAIL_INT(ub),
+		    (u_longlong_t)MMP_INTERVAL(ub),
+		    (u_longlong_t)import_intervals);
 
 	} else if (MMP_INTERVAL_VALID(ub) && MMP_FAIL_INT_VALID(ub) &&
 	    MMP_FAIL_INT(ub) == 0) {
@@ -3103,8 +3109,10 @@ spa_activity_check_duration(spa_t *spa, uberblock_t *ub)
 
 		zfs_dbgmsg("fail_intvals=0 import_delay=%llu ub_mmp "
 		    "mmp_interval=%llu ub_mmp_delay=%llu "
-		    "import_intervals=%u", import_delay, MMP_INTERVAL(ub),
-		    ub->ub_mmp_delay, import_intervals);
+		    "import_intervals=%llu", (u_longlong_t)import_delay,
+		    (u_longlong_t)MMP_INTERVAL(ub),
+		    (u_longlong_t)ub->ub_mmp_delay,
+		    (u_longlong_t)import_intervals);
 
 	} else if (MMP_VALID(ub)) {
 		/*
@@ -3115,15 +3123,18 @@ spa_activity_check_duration(spa_t *spa, uberblock_t *ub)
 		    ub->ub_mmp_delay) * import_intervals);
 
 		zfs_dbgmsg("import_delay=%llu ub_mmp_delay=%llu "
-		    "import_intervals=%u leaves=%u", import_delay,
-		    ub->ub_mmp_delay, import_intervals,
+		    "import_intervals=%llu leaves=%u",
+		    (u_longlong_t)import_delay,
+		    (u_longlong_t)ub->ub_mmp_delay,
+		    (u_longlong_t)import_intervals,
 		    vdev_count_leaves(spa));
 	} else {
 		/* Using local tunings is the only reasonable option */
 		zfs_dbgmsg("pool last imported on non-MMP aware "
 		    "host using import_delay=%llu multihost_interval=%llu "
-		    "import_intervals=%u", import_delay, multihost_interval,
-		    import_intervals);
+		    "import_intervals=%llu", (u_longlong_t)import_delay,
+		    (u_longlong_t)multihost_interval,
+		    (u_longlong_t)import_intervals);
 	}
 
 	return (import_delay);
@@ -3191,8 +3202,11 @@ spa_activity_check(spa_t *spa, uberblock_t *ub, nvlist_t *config)
 			    "txg %llu ub_txg  %llu "
 			    "timestamp %llu ub_timestamp  %llu "
 			    "mmp_config %#llx ub_mmp_config %#llx",
-			    txg, ub->ub_txg, timestamp, ub->ub_timestamp,
-			    mmp_config, ub->ub_mmp_config);
+			    (u_longlong_t)txg, (u_longlong_t)ub->ub_txg,
+			    (u_longlong_t)timestamp,
+			    (u_longlong_t)ub->ub_timestamp,
+			    (u_longlong_t)mmp_config,
+			    (u_longlong_t)ub->ub_mmp_config);
 
 			error = SET_ERROR(EREMOTEIO);
 			break;
diff --git a/module/zfs/spa_checkpoint.c b/module/zfs/spa_checkpoint.c
index 5fb6144672..09f6299685 100644
--- a/module/zfs/spa_checkpoint.c
+++ b/module/zfs/spa_checkpoint.c
@@ -337,17 +337,18 @@ spa_checkpoint_discard_thread_sync(void *arg, dmu_tx_t *tx)
 	spa_checkpoint_accounting_verify(vd->vdev_spa);
 #endif
 
-	zfs_dbgmsg("discarding checkpoint: txg %llu, vdev id %d, "
+	zfs_dbgmsg("discarding checkpoint: txg %llu, vdev id %lld, "
 	    "deleted %llu words - %llu words are left",
-	    tx->tx_txg, vd->vdev_id, (words_before - words_after),
-	    words_after);
+	    (u_longlong_t)tx->tx_txg, (longlong_t)vd->vdev_id,
+	    (u_longlong_t)(words_before - words_after),
+	    (u_longlong_t)words_after);
 
 	if (error != EINTR) {
 		if (error != 0) {
-			zfs_panic_recover("zfs: error %d was returned "
+			zfs_panic_recover("zfs: error %lld was returned "
 			    "while incrementally destroying the checkpoint "
-			    "space map of vdev %llu\n",
-			    error, vd->vdev_id);
+			    "space map of vdev %u\n",
+			    (longlong_t)error, vd->vdev_id);
 		}
 		ASSERT0(words_after);
 		ASSERT0(space_map_allocated(vd->vdev_checkpoint_sm));
diff --git a/module/zfs/spa_history.c b/module/zfs/spa_history.c
index 0482e0f6c3..dae06e46c3 100644
--- a/module/zfs/spa_history.c
+++ b/module/zfs/spa_history.c
@@ -296,14 +296,17 @@ spa_history_log_sync(void *arg, dmu_tx_t *tx)
 	} else if (nvlist_exists(nvl, ZPOOL_HIST_INT_NAME)) {
 		if (nvlist_exists(nvl, ZPOOL_HIST_DSNAME)) {
 			zfs_dbgmsg("txg %lld %s %s (id %llu) %s",
-			    fnvlist_lookup_uint64(nvl, ZPOOL_HIST_TXG),
+			    (longlong_t)fnvlist_lookup_uint64(nvl,
+			    ZPOOL_HIST_TXG),
 			    fnvlist_lookup_string(nvl, ZPOOL_HIST_INT_NAME),
 			    fnvlist_lookup_string(nvl, ZPOOL_HIST_DSNAME),
-			    fnvlist_lookup_uint64(nvl, ZPOOL_HIST_DSID),
+			    (u_longlong_t)fnvlist_lookup_uint64(nvl,
+			    ZPOOL_HIST_DSID),
 			    fnvlist_lookup_string(nvl, ZPOOL_HIST_INT_STR));
 		} else {
 			zfs_dbgmsg("txg %lld %s %s",
-			    fnvlist_lookup_uint64(nvl, ZPOOL_HIST_TXG),
+			    (longlong_t)fnvlist_lookup_uint64(nvl,
+			    ZPOOL_HIST_TXG),
 			    fnvlist_lookup_string(nvl, ZPOOL_HIST_INT_NAME),
 			    fnvlist_lookup_string(nvl, ZPOOL_HIST_INT_STR));
 		}
diff --git a/module/zfs/spa_misc.c b/module/zfs/spa_misc.c
index 1a2e5abc53..65b0988d67 100644
--- a/module/zfs/spa_misc.c
+++ b/module/zfs/spa_misc.c
@@ -615,7 +615,7 @@ spa_deadman(void *arg)
 
 	zfs_dbgmsg("slow spa_sync: started %llu seconds ago, calls %llu",
 	    (gethrtime() - spa->spa_sync_starttime) / NANOSEC,
-	    ++spa->spa_deadman_calls);
+	    (u_longlong_t)++spa->spa_deadman_calls);
 	if (zfs_deadman_enabled)
 		vdev_deadman(spa->spa_root_vdev, FTAG);
 
diff --git a/module/zfs/space_map.c b/module/zfs/space_map.c
index 3db7d19919..138e6c75ed 100644
--- a/module/zfs/space_map.c
+++ b/module/zfs/space_map.c
@@ -877,9 +877,11 @@ space_map_truncate(space_map_t *sm, int blocksize, dmu_tx_t *tx)
 	    doi.doi_data_block_size != blocksize ||
 	    doi.doi_metadata_block_size != 1 << space_map_ibs) {
 		zfs_dbgmsg("txg %llu, spa %s, sm %px, reallocating "
-		    "object[%llu]: old bonus %u, old blocksz %u",
-		    dmu_tx_get_txg(tx), spa_name(spa), sm, sm->sm_object,
-		    doi.doi_bonus_size, doi.doi_data_block_size);
+		    "object[%llu]: old bonus %llu, old blocksz %u",
+		    (u_longlong_t)dmu_tx_get_txg(tx), spa_name(spa), sm,
+		    (u_longlong_t)sm->sm_object,
+		    (u_longlong_t)doi.doi_bonus_size,
+		    doi.doi_data_block_size);
 
 		space_map_free(sm, tx);
 		dmu_buf_rele(sm->sm_dbuf, sm);
diff --git a/module/zfs/txg.c b/module/zfs/txg.c
index 497e19dd58..c55b1d8f96 100644
--- a/module/zfs/txg.c
+++ b/module/zfs/txg.c
@@ -554,7 +554,8 @@ txg_sync_thread(void *arg)
 		    !txg_has_quiesced_to_sync(dp) &&
 		    dp->dp_dirty_total < dirty_min_bytes) {
 			dprintf("waiting; tx_synced=%llu waiting=%llu dp=%p\n",
-			    tx->tx_synced_txg, tx->tx_sync_txg_waiting, dp);
+			    (u_longlong_t)tx->tx_synced_txg,
+			    (u_longlong_t)tx->tx_sync_txg_waiting, dp);
 			txg_thread_wait(tx, &cpr, &tx->tx_sync_more_cv, timer);
 			delta = ddi_get_lbolt() - start;
 			timer = (delta > timeout ? 0 : timeout - delta);
@@ -587,7 +588,8 @@ txg_sync_thread(void *arg)
 		cv_broadcast(&tx->tx_quiesce_more_cv);
 
 		dprintf("txg=%llu quiesce_txg=%llu sync_txg=%llu\n",
-		    txg, tx->tx_quiesce_txg_waiting, tx->tx_sync_txg_waiting);
+		    (u_longlong_t)txg, (u_longlong_t)tx->tx_quiesce_txg_waiting,
+		    (u_longlong_t)tx->tx_sync_txg_waiting);
 		mutex_exit(&tx->tx_sync_lock);
 
 		txg_stat_t *ts = spa_txg_history_init_io(spa, txg, dp);
@@ -638,8 +640,9 @@ txg_quiesce_thread(void *arg)
 
 		txg = tx->tx_open_txg;
 		dprintf("txg=%llu quiesce_txg=%llu sync_txg=%llu\n",
-		    txg, tx->tx_quiesce_txg_waiting,
-		    tx->tx_sync_txg_waiting);
+		    (u_longlong_t)txg,
+		    (u_longlong_t)tx->tx_quiesce_txg_waiting,
+		    (u_longlong_t)tx->tx_sync_txg_waiting);
 		tx->tx_quiescing_txg = txg;
 
 		mutex_exit(&tx->tx_sync_lock);
@@ -649,7 +652,8 @@ txg_quiesce_thread(void *arg)
 		/*
 		 * Hand this txg off to the sync thread.
 		 */
-		dprintf("quiesce done, handing off txg %llu\n", txg);
+		dprintf("quiesce done, handing off txg %llu\n",
+		    (u_longlong_t)txg);
 		tx->tx_quiescing_txg = 0;
 		tx->tx_quiesced_txg = txg;
 		DTRACE_PROBE2(txg__quiesced, dsl_pool_t *, dp, uint64_t, txg);
@@ -705,11 +709,13 @@ txg_wait_synced_impl(dsl_pool_t *dp, uint64_t txg, boolean_t wait_sig)
 	if (tx->tx_sync_txg_waiting < txg)
 		tx->tx_sync_txg_waiting = txg;
 	dprintf("txg=%llu quiesce_txg=%llu sync_txg=%llu\n",
-	    txg, tx->tx_quiesce_txg_waiting, tx->tx_sync_txg_waiting);
+	    (u_longlong_t)txg, (u_longlong_t)tx->tx_quiesce_txg_waiting,
+	    (u_longlong_t)tx->tx_sync_txg_waiting);
 	while (tx->tx_synced_txg < txg) {
 		dprintf("broadcasting sync more "
 		    "tx_synced=%llu waiting=%llu dp=%px\n",
-		    tx->tx_synced_txg, tx->tx_sync_txg_waiting, dp);
+		    (u_longlong_t)tx->tx_synced_txg,
+		    (u_longlong_t)tx->tx_sync_txg_waiting, dp);
 		cv_broadcast(&tx->tx_sync_more_cv);
 		if (wait_sig) {
 			/*
@@ -764,7 +770,8 @@ txg_wait_open(dsl_pool_t *dp, uint64_t txg, boolean_t should_quiesce)
 	if (tx->tx_quiesce_txg_waiting < txg && should_quiesce)
 		tx->tx_quiesce_txg_waiting = txg;
 	dprintf("txg=%llu quiesce_txg=%llu sync_txg=%llu\n",
-	    txg, tx->tx_quiesce_txg_waiting, tx->tx_sync_txg_waiting);
+	    (u_longlong_t)txg, (u_longlong_t)tx->tx_quiesce_txg_waiting,
+	    (u_longlong_t)tx->tx_sync_txg_waiting);
 	while (tx->tx_open_txg < txg) {
 		cv_broadcast(&tx->tx_quiesce_more_cv);
 		/*
diff --git a/module/zfs/vdev.c b/module/zfs/vdev.c
index 5e14d71f19..4e316d8135 100644
--- a/module/zfs/vdev.c
+++ b/module/zfs/vdev.c
@@ -165,7 +165,8 @@ vdev_dbgmsg_print_tree(vdev_t *vd, int indent)
 	char state[20];
 
 	if (vd->vdev_ishole || vd->vdev_ops == &vdev_missing_ops) {
-		zfs_dbgmsg("%*svdev %u: %s", indent, "", vd->vdev_id,
+		zfs_dbgmsg("%*svdev %llu: %s", indent, "",
+		    (u_longlong_t)vd->vdev_id,
 		    vd->vdev_ops->vdev_op_type);
 		return;
 	}
@@ -5208,7 +5209,7 @@ vdev_deadman(vdev_t *vd, char *tag)
 			zio_t *fio;
 			uint64_t delta;
 
-			zfs_dbgmsg("slow vdev: %s has %d active IOs",
+			zfs_dbgmsg("slow vdev: %s has %lu active IOs",
 			    vd->vdev_path, avl_numnodes(&vq->vq_active_tree));
 
 			/*
diff --git a/module/zfs/vdev_indirect.c b/module/zfs/vdev_indirect.c
index 6362683ae9..1b05ff03a0 100644
--- a/module/zfs/vdev_indirect.c
+++ b/module/zfs/vdev_indirect.c
@@ -529,8 +529,9 @@ spa_condense_indirect_complete_sync(void *arg, dmu_tx_t *tx)
 	zfs_dbgmsg("finished condense of vdev %llu in txg %llu: "
 	    "new mapping object %llu has %llu entries "
 	    "(was %llu entries)",
-	    vd->vdev_id, dmu_tx_get_txg(tx), vic->vic_mapping_object,
-	    new_count, old_count);
+	    (u_longlong_t)vd->vdev_id, (u_longlong_t)dmu_tx_get_txg(tx),
+	    (u_longlong_t)vic->vic_mapping_object,
+	    (u_longlong_t)new_count, (u_longlong_t)old_count);
 
 	vdev_config_dirty(spa->spa_root_vdev);
 }
@@ -796,7 +797,7 @@ spa_condense_indirect_start_sync(vdev_t *vd, dmu_tx_t *tx)
 
 	zfs_dbgmsg("starting condense of vdev %llu in txg %llu: "
 	    "posm=%llu nm=%llu",
-	    vd->vdev_id, dmu_tx_get_txg(tx),
+	    (u_longlong_t)vd->vdev_id, (u_longlong_t)dmu_tx_get_txg(tx),
 	    (u_longlong_t)scip->scip_prev_obsolete_sm_object,
 	    (u_longlong_t)scip->scip_next_mapping_object);
 
diff --git a/module/zfs/vdev_removal.c b/module/zfs/vdev_removal.c
index a758fe4fb3..8b0c76ff0a 100644
--- a/module/zfs/vdev_removal.c
+++ b/module/zfs/vdev_removal.c
@@ -345,8 +345,9 @@ vdev_remove_initiate_sync(void *arg, dmu_tx_t *tx)
 	vdev_config_dirty(vd);
 
 	zfs_dbgmsg("starting removal thread for vdev %llu (%px) in txg %llu "
-	    "im_obj=%llu", vd->vdev_id, vd, dmu_tx_get_txg(tx),
-	    vic->vic_mapping_object);
+	    "im_obj=%llu", (u_longlong_t)vd->vdev_id, vd,
+	    (u_longlong_t)dmu_tx_get_txg(tx),
+	    (u_longlong_t)vic->vic_mapping_object);
 
 	spa_history_log_internal(spa, "vdev remove started", tx,
 	    "%s vdev %llu %s", spa_name(spa), (u_longlong_t)vd->vdev_id,
@@ -474,7 +475,8 @@ spa_restart_removal(spa_t *spa)
 	if (!spa_writeable(spa))
 		return;
 
-	zfs_dbgmsg("restarting removal of %llu", svr->svr_vdev_id);
+	zfs_dbgmsg("restarting removal of %llu",
+	    (u_longlong_t)svr->svr_vdev_id);
 	svr->svr_thread = thread_create(NULL, 0, spa_vdev_remove_thread, spa,
 	    0, &p0, TS_RUN, minclsyspri);
 }
@@ -1196,7 +1198,7 @@ vdev_remove_complete(spa_t *spa)
 	    ESC_ZFS_VDEV_REMOVE_DEV);
 
 	zfs_dbgmsg("finishing device removal for vdev %llu in txg %llu",
-	    vd->vdev_id, txg);
+	    (u_longlong_t)vd->vdev_id, (u_longlong_t)txg);
 
 	/*
 	 * Discard allocation state.
@@ -1490,8 +1492,9 @@ spa_vdev_remove_thread(void *arg)
 
 		vca.vca_msp = msp;
 		zfs_dbgmsg("copying %llu segments for metaslab %llu",
-		    zfs_btree_numnodes(&svr->svr_allocd_segs->rt_root),
-		    msp->ms_id);
+		    (u_longlong_t)zfs_btree_numnodes(
+		    &svr->svr_allocd_segs->rt_root),
+		    (u_longlong_t)msp->ms_id);
 
 		while (!svr->svr_thread_exit &&
 		    !range_tree_is_empty(svr->svr_allocd_segs)) {
@@ -1592,8 +1595,8 @@ spa_vdev_remove_thread(void *arg)
 		    vca.vca_write_error_bytes > 0)) {
 			zfs_dbgmsg("canceling removal due to IO errors: "
 			    "[read_error_bytes=%llu] [write_error_bytes=%llu]",
-			    vca.vca_read_error_bytes,
-			    vca.vca_write_error_bytes);
+			    (u_longlong_t)vca.vca_read_error_bytes,
+			    (u_longlong_t)vca.vca_write_error_bytes);
 			spa_vdev_remove_cancel_impl(spa);
 		}
 	} else {
@@ -1765,7 +1768,7 @@ spa_vdev_remove_cancel_sync(void *arg, dmu_tx_t *tx)
 	vdev_config_dirty(vd);
 
 	zfs_dbgmsg("canceled device removal for vdev %llu in %llu",
-	    vd->vdev_id, dmu_tx_get_txg(tx));
+	    (u_longlong_t)vd->vdev_id, (u_longlong_t)dmu_tx_get_txg(tx));
 	spa_history_log_internal(spa, "vdev remove canceled", tx,
 	    "%s vdev %llu %s", spa_name(spa),
 	    (u_longlong_t)vd->vdev_id,
diff --git a/module/zfs/zap.c b/module/zfs/zap.c
index c0c280c520..6f03beef3b 100644
--- a/module/zfs/zap.c
+++ b/module/zfs/zap.c
@@ -221,7 +221,8 @@ zap_table_grow(zap_t *zap, zap_table_phys_t *tbl,
 	tbl->zt_blks_copied++;
 
 	dprintf("copied block %llu of %llu\n",
-	    tbl->zt_blks_copied, tbl->zt_numblks);
+	    (u_longlong_t)tbl->zt_blks_copied,
+	    (u_longlong_t)tbl->zt_numblks);
 
 	if (tbl->zt_blks_copied == tbl->zt_numblks) {
 		(void) dmu_free_range(zap->zap_objset, zap->zap_object,
@@ -234,7 +235,7 @@ zap_table_grow(zap_t *zap, zap_table_phys_t *tbl,
 		tbl->zt_blks_copied = 0;
 
 		dprintf("finished; numblocks now %llu (%uk entries)\n",
-		    tbl->zt_numblks, 1<<(tbl->zt_shift-10));
+		    (u_longlong_t)tbl->zt_numblks, 1<<(tbl->zt_shift-10));
 	}
 
 	return (0);
@@ -249,7 +250,8 @@ zap_table_store(zap_t *zap, zap_table_phys_t *tbl, uint64_t idx, uint64_t val,
 	ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
 	ASSERT(tbl->zt_blk != 0);
 
-	dprintf("storing %llx at index %llx\n", val, idx);
+	dprintf("storing %llx at index %llx\n", (u_longlong_t)val,
+	    (u_longlong_t)idx);
 
 	uint64_t blk = idx >> (bs-3);
 	uint64_t off = idx & ((1<<(bs-3))-1);
diff --git a/module/zfs/zap_micro.c b/module/zfs/zap_micro.c
index 5d9bc20760..b4611685b2 100644
--- a/module/zfs/zap_micro.c
+++ b/module/zfs/zap_micro.c
@@ -563,7 +563,7 @@ zap_lockdir_impl(dmu_buf_t *db, void *tag, dmu_tx_t *tx,
 		uint64_t newsz = db->db_size + SPA_MINBLOCKSIZE;
 		if (newsz > MZAP_MAX_BLKSZ) {
 			dprintf("upgrading obj %llu: num_entries=%u\n",
-			    obj, zap->zap_m.zap_num_entries);
+			    (u_longlong_t)obj, zap->zap_m.zap_num_entries);
 			*zapp = zap;
 			int err = mzap_upgrade(zapp, tag, tx, 0);
 			if (err != 0)
@@ -656,7 +656,7 @@ mzap_upgrade(zap_t **zapp, void *tag, dmu_tx_t *tx, zap_flags_t flags)
 	}
 
 	dprintf("upgrading obj=%llu with %u chunks\n",
-	    zap->zap_object, nchunks);
+	    (u_longlong_t)zap->zap_object, nchunks);
 	/* XXX destroy the avl later, so we can use the stored hash value */
 	mze_destroy(zap);
 
@@ -667,7 +667,7 @@ mzap_upgrade(zap_t **zapp, void *tag, dmu_tx_t *tx, zap_flags_t flags)
 		if (mze->mze_name[0] == 0)
 			continue;
 		dprintf("adding %s=%llu\n",
-		    mze->mze_name, mze->mze_value);
+		    mze->mze_name, (u_longlong_t)mze->mze_value);
 		zap_name_t *zn = zap_name_alloc(zap, mze->mze_name, 0);
 		/* If we fail here, we would end up losing entries */
 		VERIFY0(fzap_add_cd(zn, 8, 1, &mze->mze_value, mze->mze_cd,
@@ -1339,7 +1339,8 @@ zap_update(objset_t *os, uint64_t zapobj, const char *name,
 	} else if (integer_size != 8 || num_integers != 1 ||
 	    strlen(name) >= MZAP_NAME_LEN) {
 		dprintf("upgrading obj %llu: intsz=%u numint=%llu name=%s\n",
-		    zapobj, integer_size, num_integers, name);
+		    (u_longlong_t)zapobj, integer_size,
+		    (u_longlong_t)num_integers, name);
 		err = mzap_upgrade(&zn->zn_zap, FTAG, tx, 0);
 		if (err == 0) {
 			err = fzap_update(zn, integer_size, num_integers,
diff --git a/module/zfs/zcp.c b/module/zfs/zcp.c
index 1ad53eae1e..f724b44baf 100644
--- a/module/zfs/zcp.c
+++ b/module/zfs/zcp.c
@@ -654,7 +654,8 @@ zcp_debug(lua_State *state)
 
 	dbgstring = lua_tostring(state, 1);
 
-	zfs_dbgmsg("txg %lld ZCP: %s", ri->zri_tx->tx_txg, dbgstring);
+	zfs_dbgmsg("txg %lld ZCP: %s", (longlong_t)ri->zri_tx->tx_txg,
+	    dbgstring);
 
 	return (0);
 }
diff --git a/module/zfs/zil.c b/module/zfs/zil.c
index d9c3042084..7f11c3913c 100644
--- a/module/zfs/zil.c
+++ b/module/zfs/zil.c
@@ -1960,7 +1960,7 @@ zil_itx_assign(zilog_t *zilog, itx_t *itx, dmu_tx_t *tx)
 			 * This should be rare.
 			 */
 			zfs_dbgmsg("zil_itx_assign: missed itx cleanup for "
-			    "txg %llu", itxg->itxg_txg);
+			    "txg %llu", (u_longlong_t)itxg->itxg_txg);
 			clean = itxg->itxg_itxs;
 		}
 		itxg->itxg_txg = txg;
@@ -3285,7 +3285,8 @@ zil_close(zilog_t *zilog)
 		txg_wait_synced(zilog->zl_dmu_pool, txg);
 
 	if (zilog_is_dirty(zilog))
-		zfs_dbgmsg("zil (%px) is dirty, txg %llu", zilog, txg);
+		zfs_dbgmsg("zil (%px) is dirty, txg %llu", zilog,
+		    (u_longlong_t)txg);
 	if (txg < spa_freeze_txg(zilog->zl_spa))
 		VERIFY(!zilog_is_dirty(zilog));
 
diff --git a/module/zfs/zio.c b/module/zfs/zio.c
index 66ac545c79..e33d36dab5 100644
--- a/module/zfs/zio.c
+++ b/module/zfs/zio.c
@@ -2014,18 +2014,24 @@ zio_deadman_impl(zio_t *pio, int ziodepth)
 
 		zfs_dbgmsg("slow zio[%d]: zio=%px timestamp=%llu "
 		    "delta=%llu queued=%llu io=%llu "
-		    "path=%s last=%llu "
-		    "type=%d priority=%d flags=0x%x "
-		    "stage=0x%x pipeline=0x%x pipeline-trace=0x%x "
-		    "objset=%llu object=%llu level=%llu blkid=%llu "
-		    "offset=%llu size=%llu error=%d",
+		    "path=%s "
+		    "last=%llu type=%d "
+		    "priority=%d flags=0x%x stage=0x%x "
+		    "pipeline=0x%x pipeline-trace=0x%x "
+		    "objset=%llu object=%llu "
+		    "level=%llu blkid=%llu "
+		    "offset=%llu size=%llu "
+		    "error=%d",
 		    ziodepth, pio, pio->io_timestamp,
-		    delta, pio->io_delta, pio->io_delay,
-		    vd ? vd->vdev_path : "NULL", vq ? vq->vq_io_complete_ts : 0,
-		    pio->io_type, pio->io_priority, pio->io_flags,
-		    pio->io_stage, pio->io_pipeline, pio->io_pipeline_trace,
-		    zb->zb_objset, zb->zb_object, zb->zb_level, zb->zb_blkid,
-		    pio->io_offset, pio->io_size, pio->io_error);
+		    (u_longlong_t)delta, pio->io_delta, pio->io_delay,
+		    vd ? vd->vdev_path : "NULL",
+		    vq ? vq->vq_io_complete_ts : 0, pio->io_type,
+		    pio->io_priority, pio->io_flags, pio->io_stage,
+		    pio->io_pipeline, pio->io_pipeline_trace,
+		    (u_longlong_t)zb->zb_objset, (u_longlong_t)zb->zb_object,
+		    (u_longlong_t)zb->zb_level, (u_longlong_t)zb->zb_blkid,
+		    (u_longlong_t)pio->io_offset, (u_longlong_t)pio->io_size,
+		    pio->io_error);
 		(void) zfs_ereport_post(FM_EREPORT_ZFS_DEADMAN,
 		    pio->io_spa, vd, zb, pio, 0);
 
@@ -3533,7 +3539,8 @@ zio_dva_allocate(zio_t *zio)
 		if (zfs_flags & ZFS_DEBUG_METASLAB_ALLOC) {
 			zfs_dbgmsg("%s: metaslab allocation failure, "
 			    "trying normal class: zio %px, size %llu, error %d",
-			    spa_name(spa), zio, zio->io_size, error);
+			    spa_name(spa), zio, (u_longlong_t)zio->io_size,
+			    error);
 		}
 
 		error = metaslab_alloc(spa, mc, zio->io_size, bp,
@@ -3545,7 +3552,8 @@ zio_dva_allocate(zio_t *zio)
 		if (zfs_flags & ZFS_DEBUG_METASLAB_ALLOC) {
 			zfs_dbgmsg("%s: metaslab allocation failure, "
 			    "trying ganging: zio %px, size %llu, error %d",
-			    spa_name(spa), zio, zio->io_size, error);
+			    spa_name(spa), zio, (u_longlong_t)zio->io_size,
+			    error);
 		}
 		return (zio_write_gang_block(zio, mc));
 	}
@@ -3554,7 +3562,8 @@ zio_dva_allocate(zio_t *zio)
 		    (zfs_flags & ZFS_DEBUG_METASLAB_ALLOC)) {
 			zfs_dbgmsg("%s: metaslab allocation failure: zio %px, "
 			    "size %llu, error %d",
-			    spa_name(spa), zio, zio->io_size, error);
+			    spa_name(spa), zio, (u_longlong_t)zio->io_size,
+			    error);
 		}
 		zio->io_error = error;
 	}
@@ -3680,7 +3689,8 @@ zio_alloc_zil(spa_t *spa, objset_t *os, uint64_t txg, blkptr_t *new_bp,
 		}
 	} else {
 		zfs_dbgmsg("%s: zil block allocation failure: "
-		    "size %llu, error %d", spa_name(spa), size, error);
+		    "size %llu, error %d", spa_name(spa), (u_longlong_t)size,
+		    error);
 	}
 
 	return (error);