diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index e99f413..c29410a 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -580,7 +580,8 @@
 	struct dm_target_callbacks callbacks;
 
 	dm_block_t low_water_blocks;
-	struct pool_features pf;
+	struct pool_features requested_pf; /* Features requested during table load */
+	struct pool_features adjusted_pf;  /* Features used after adjusting for constituent devices */
 };
 
 /*
@@ -1848,21 +1849,36 @@
 
 /*
  * If discard_passdown was enabled verify that the data device
- * supports discards.  Disable discard_passdown if not; otherwise
- * -EOPNOTSUPP will be returned.
+ * supports discards.  Disable discard_passdown if not.
  */
-static void disable_passdown_if_not_supported(struct pool_c *pt,
-					      struct pool_features *pf)
+static void disable_passdown_if_not_supported(struct pool_c *pt)
 {
+	struct pool *pool = pt->pool;
+	struct block_device *data_bdev = pt->data_dev->bdev;
+	struct queue_limits *data_limits = &bdev_get_queue(data_bdev)->limits;
+	sector_t block_size = pool->sectors_per_block << SECTOR_SHIFT;
+	const char *reason = NULL;
 	char buf[BDEVNAME_SIZE];
 
-	if (!pf->discard_passdown || data_dev_supports_discard(pt))
+	if (!pt->adjusted_pf.discard_passdown)
 		return;
 
-	DMWARN("Discard unsupported by data device (%s): Disabling discard passdown.",
-	       bdevname(pt->data_dev->bdev, buf));
+	if (!data_dev_supports_discard(pt))
+		reason = "discard unsupported";
 
-	pf->discard_passdown = false;
+	else if (data_limits->max_discard_sectors < pool->sectors_per_block)
+		reason = "max discard sectors smaller than a block";
+
+	else if (data_limits->discard_granularity > block_size)
+		reason = "discard granularity larger than a block";
+
+	else if (block_size & (data_limits->discard_granularity - 1))
+		reason = "discard granularity not a factor of block size";
+
+	if (reason) {
+		DMWARN("Data device (%s) %s: Disabling discard passdown.", bdevname(data_bdev, buf), reason);
+		pt->adjusted_pf.discard_passdown = false;
+	}
 }
 
 static int bind_control_target(struct pool *pool, struct dm_target *ti)
@@ -1873,16 +1889,15 @@
 	 * We want to make sure that degraded pools are never upgraded.
 	 */
 	enum pool_mode old_mode = pool->pf.mode;
-	enum pool_mode new_mode = pt->pf.mode;
+	enum pool_mode new_mode = pt->adjusted_pf.mode;
 
 	if (old_mode > new_mode)
 		new_mode = old_mode;
 
 	pool->ti = ti;
 	pool->low_water_blocks = pt->low_water_blocks;
-	pool->pf = pt->pf;
+	pool->pf = pt->adjusted_pf;
 
-	disable_passdown_if_not_supported(pt, &pool->pf);
 	set_pool_mode(pool, new_mode);
 
 	return 0;
@@ -2271,7 +2286,7 @@
 	pt->metadata_dev = metadata_dev;
 	pt->data_dev = data_dev;
 	pt->low_water_blocks = low_water_blocks;
-	pt->pf = pf;
+	pt->adjusted_pf = pt->requested_pf = pf;
 	ti->num_flush_requests = 1;
 
 	/*
@@ -2718,7 +2733,7 @@
 		       format_dev_t(buf2, pt->data_dev->bdev->bd_dev),
 		       (unsigned long)pool->sectors_per_block,
 		       (unsigned long long)pt->low_water_blocks);
-		emit_flags(&pt->pf, result, sz, maxlen);
+		emit_flags(&pt->requested_pf, result, sz, maxlen);
 		break;
 	}
 
@@ -2747,19 +2762,21 @@
 	return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
 }
 
-static void set_discard_limits(struct pool *pool, struct queue_limits *limits)
+static void set_discard_limits(struct pool_c *pt, struct queue_limits *limits)
 {
-	/*
-	 * FIXME: these limits may be incompatible with the pool's data device
-	 */
+	struct pool *pool = pt->pool;
+	struct queue_limits *data_limits;
+
 	limits->max_discard_sectors = pool->sectors_per_block;
 
 	/*
-	 * This is just a hint, and not enforced.  We have to cope with
-	 * bios that cover a block partially.  A discard that spans a block
-	 * boundary is not sent to this target.
+	 * discard_granularity is just a hint, and not enforced.
 	 */
-	limits->discard_granularity = pool->sectors_per_block << SECTOR_SHIFT;
+	if (pt->adjusted_pf.discard_passdown) {
+		data_limits = &bdev_get_queue(pt->data_dev->bdev)->limits;
+		limits->discard_granularity = data_limits->discard_granularity;
+	} else
+		limits->discard_granularity = pool->sectors_per_block << SECTOR_SHIFT;
 }
 
 static void pool_io_hints(struct dm_target *ti, struct queue_limits *limits)
@@ -2769,15 +2786,25 @@
 
 	blk_limits_io_min(limits, 0);
 	blk_limits_io_opt(limits, pool->sectors_per_block << SECTOR_SHIFT);
-	if (pool->pf.discard_enabled)
-		set_discard_limits(pool, limits);
+
+	/*
+	 * pt->adjusted_pf is a staging area for the actual features to use.
+	 * They get transferred to the live pool in bind_control_target()
+	 * called from pool_preresume().
+	 */
+	if (!pt->adjusted_pf.discard_enabled)
+		return;
+
+	disable_passdown_if_not_supported(pt);
+
+	set_discard_limits(pt, limits);
 }
 
 static struct target_type pool_target = {
 	.name = "thin-pool",
 	.features = DM_TARGET_SINGLETON | DM_TARGET_ALWAYS_WRITEABLE |
 		    DM_TARGET_IMMUTABLE,
-	.version = {1, 3, 0},
+	.version = {1, 4, 0},
 	.module = THIS_MODULE,
 	.ctr = pool_ctr,
 	.dtr = pool_dtr,
@@ -3056,19 +3083,19 @@
 	return 0;
 }
 
+/*
+ * A thin device always inherits its queue limits from its pool.
+ */
 static void thin_io_hints(struct dm_target *ti, struct queue_limits *limits)
 {
 	struct thin_c *tc = ti->private;
-	struct pool *pool = tc->pool;
 
-	blk_limits_io_min(limits, 0);
-	blk_limits_io_opt(limits, pool->sectors_per_block << SECTOR_SHIFT);
-	set_discard_limits(pool, limits);
+	*limits = bdev_get_queue(tc->pool_dev->bdev)->limits;
 }
 
 static struct target_type thin_target = {
 	.name = "thin",
-	.version = {1, 3, 0},
+	.version = {1, 4, 0},
 	.module	= THIS_MODULE,
 	.ctr = thin_ctr,
 	.dtr = thin_dtr,