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

mtd: nand: Fix writing mtdoops to nand flash.

to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: mtd-nand-fix-writing-mtdoops-to-nand-flash.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 30863e38ebeb500a31cecee8096fb5002677dd9b Mon Sep 17 00:00:00 2001

From: Brent Taylor motobud@gmail.com Date: Mon, 30 Oct 2017 22:32:45 -0500 Subject: mtd: nand: Fix writing mtdoops to nand flash.

From: Brent Taylor motobud@gmail.com

commit 30863e38ebeb500a31cecee8096fb5002677dd9b upstream.

When mtdoops calls mtd_panic_write(), it eventually calls panic_nand_write() in nand_base.c. In order to properly wait for the nand chip to be ready in panic_nand_wait(), the chip must first be selected.

When using the atmel nand flash controller, a panic would occur due to a NULL pointer exception.

Fixes: 2af7c6539931 ("mtd: Add panic_write for NAND flashes") Cc: stable@vger.kernel.org Signed-off-by: Brent Taylor motobud@gmail.com Signed-off-by: Boris Brezillon boris.brezillon@free-electrons.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/mtd/nand/nand_base.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)

--- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -2663,15 +2663,18 @@ static int panic_nand_write(struct mtd_i size_t *retlen, const uint8_t *buf) { struct nand_chip *chip = mtd->priv; + int chipnr = (int)(to >> chip->chip_shift); struct mtd_oob_ops ops; int ret;

- /* Wait for the device to get ready */ - panic_nand_wait(mtd, chip, 400); - /* Grab the device */ panic_nand_get_device(chip, mtd, FL_WRITING);

+ chip->select_chip(mtd, chipnr); + + /* Wait for the device to get ready */ + panic_nand_wait(mtd, chip, 400); + memset(&ops, 0, sizeof(ops)); ops.len = len; ops.datbuf = (uint8_t *)buf;

Patches currently in stable-queue which might be from motobud@gmail.com are

queue-4.4/mtd-nand-fix-writing-mtdoops-to-nand-flash.patch