4.4-stable review patch. If anyone has any objections, please let me know.
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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;