Patch "mtd: nand: Drop mtd.owner requirement in nand_scan" has been added to the 4.4-stable tree

Patch "mtd: nand: Drop mtd.owner requirement in nand_scan" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    mtd: nand: Drop mtd.owner requirement in nand_scan

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     mtd-nand-drop-mtd.owner-requirement-in-nand_scan.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 20c07a5bf094198ff2382aa5e7c930b3c9807792 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ezequiel=20Garc=C3=ADa?= <ezequiel@vanguardiasur.com.ar>
Date: Fri, 1 Apr 2016 18:29:23 -0300
Subject: mtd: nand: Drop mtd.owner requirement in nand_scan

From: Ezequiel García <ezequiel@vanguardiasur.com.ar>

commit 20c07a5bf094198ff2382aa5e7c930b3c9807792 upstream.

Since commit 807f16d4db95 ("mtd: core: set some defaults
when dev.parent is set"), it's now legal for drivers
to call nand_scan and nand_scan_ident without setting
mtd.owner.

Drop the check and while at it remove the BUG() abuse.

Fixes: 807f16d4db95 ("mtd: core: set some defaults when dev.parent is set")
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
[Brian: editorial note - while commit 807f16d4db95 wasn't explicitly
    broken, some follow-up commits in the v4.4 release broke a few
    drivers, since they would hit this BUG() if they used nand_scan()
    and were built as modules]
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/mtd/nand/nand_base.c |   10 +---------
 1 file changed, 1 insertion(+), 9 deletions(-)

--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -3979,7 +3979,6 @@ static int nand_dt_init(struct mtd_info
  * This is the first phase of the normal nand_scan() function. It reads the
  * flash ID and sets up MTD fields accordingly.
  *
- * The mtd->owner field must be set to the module of the caller.
  */
 int nand_scan_ident(struct mtd_info *mtd, int maxchips,
 		    struct nand_flash_dev *table)
@@ -4403,19 +4402,12 @@ EXPORT_SYMBOL(nand_scan_tail);
  *
  * This fills out all the uninitialized function pointers with the defaults.
  * The flash ID is read and the mtd/chip structures are filled with the
- * appropriate values. The mtd->owner field must be set to the module of the
- * caller.
+ * appropriate values.
  */
 int nand_scan(struct mtd_info *mtd, int maxchips)
 {
 	int ret;
 
-	/* Many callers got this wrong, so check for it for a while... */
-	if (!mtd->owner && caller_is_module()) {
-		pr_crit("%s called with NULL mtd->owner!\n", __func__);
-		BUG();
-	}
-
 	ret = nand_scan_ident(mtd, maxchips, NULL);
 	if (!ret)
 		ret = nand_scan_tail(mtd);


Patches currently in stable-queue which might be from ezequiel@vanguardiasur.com.ar are

queue-4.4/mtd-nand-drop-mtd.owner-requirement-in-nand_scan.patch