[PATCH] mtd: don't try to detect UBI in too small flash partitions

[Ahmad Fatoum]

The detect callback will try to detect an UBI volume inside a partition.
If that partition happens to be smaller than 512 bytes, detect will fail
with -EINVAL.

Avoid this confusing error by early exiting in this case.

Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
---
 drivers/mtd/core.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/mtd/core.c b/drivers/mtd/core.c
index 97a7996cf68e..34f919b96ea4 100644
--- a/drivers/mtd/core.c
+++ b/drivers/mtd/core.c
@@ -599,6 +599,10 @@ static int mtd_detect(struct device *dev)
 	enum filetype filetype;
 	int npebs = mtd_div_by_eb(mtd->size, mtd);
 
+	/* No point in looking for UBI on a partition that's smaller than an erase block */
+	if (!npebs)
+		return 0;
+
 	npebs = max(npebs, 64);
 
 	/*
-- 
2.39.2