Re: [PATCH v1] mtd: ubi: Release device reference on busy detach

From: Zhihao Cheng

Date: Fri Aug 07 2026 - 21:50:40 EST


在 2026/8/8 4:45, Yuho Choi 写道:
ubi_detach_mtd_dev() obtains a device reference through ubi_get_device()
before checking whether the UBI device is busy. The busy return path drops
ubi->ref_count but leaves the device reference held, so the device object
cannot be released after a later detach.

Drop the device reference before returning -EBUSY.

Fixes: 7e84c961b2eb ("mtd: ubi: introduce pre-removal notification for UBI volumes")
Signed-off-by: Yuho Choi <dbgh9129@xxxxxxxxx>
---
drivers/mtd/ubi/build.c | 1 +
1 file changed, 1 insertion(+)

I think you have sent this patch before?
https://lore.kernel.org/linux-mtd/26c9c959-a3b6-e1de-1215-887990a46870@xxxxxxxxxx/

diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index 674ad87809df..ee6ce4471b25 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -1105,6 +1105,7 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway)
ubi->ref_count -= 1;
if (ubi->ref_count) {
if (!anyway) {
+ put_device(&ubi->dev);
spin_unlock(&ubi_devices_lock);
return -EBUSY;
}