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

From: Zev Weiss
Date: Thu Oct 14 2021 - 16:40:08 EST


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: e8e3edb95ce6 ("mtd: create per-device and module-scope debugfs entries")
Signed-off-by: Zev Weiss <zev@xxxxxxxxxxxxxxxxx>
---
drivers/mtd/mtdcore.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index e22266f63ae9..0a0fca737d43 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -724,8 +724,6 @@ 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;
@@ -741,6 +739,8 @@ 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);
--
2.33.0