mtd: core: don't remove debugfs directory if device is in use

[ Upstream commit c13de2386c ]

Previously, if del_mtd_device() failed with -EBUSY due to a non-zero
usecount, a subsequent call to attempt the deletion again would try to
remove a debugfs directory that had already been removed and panic.
With this change the second call can instead proceed safely.

Fixes: e8e3edb95c ("mtd: create per-device and module-scope debugfs entries")
Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20211014203953.5424-1-zev@bewilderbeest.net
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Zev Weiss 2021-10-14 13:39:52 -07:00 committed by Greg Kroah-Hartman
parent 59929f9a57
commit 04317e7474

View file

@ -727,8 +727,6 @@ int del_mtd_device(struct mtd_info *mtd)
mutex_lock(&mtd_table_mutex);
debugfs_remove_recursive(mtd->dbg.dfs_dir);
if (idr_find(&mtd_idr, mtd->index) != mtd) {
ret = -ENODEV;
goto out_error;
@ -744,6 +742,8 @@ int del_mtd_device(struct mtd_info *mtd)
mtd->index, mtd->name, mtd->usecount);
ret = -EBUSY;
} else {
debugfs_remove_recursive(mtd->dbg.dfs_dir);
/* Try to remove the NVMEM provider */
if (mtd->nvmem)
nvmem_unregister(mtd->nvmem);