From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f194.google.com ([209.85.223.194]:45499 "EHLO mail-io0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750832AbdK2FN4 (ORCPT ); Wed, 29 Nov 2017 00:13:56 -0500 Received: by mail-io0-f194.google.com with SMTP id e204so2386791iof.12 for ; Tue, 28 Nov 2017 21:13:56 -0800 (PST) From: motobud@gmail.com To: gregkh@linuxfoundation.org Cc: boris.brezillon@free-electrons.com, Brent Taylor , stable@vger.kernel.org Subject: [PATCH] mtd: nand: Fix writing mtdoops to nand flash Date: Tue, 28 Nov 2017 23:13:47 -0600 Message-Id: <20171129051347.1549-1-motobud@gmail.com> Sender: stable-owner@vger.kernel.org List-ID: From: Brent Taylor Gregg, I apologize for the 4.4.y patch, I screwed up the branching in my local tree and tried to submit one patch that would cover versions 4.4.y and 3.18.y. Here is a valid 4.4.y patch. -- Brent 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: # 4.4.x Signed-off-by: Brent Taylor --- drivers/mtd/nand/nand_base.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index 54ab48827258..7ba109e8cf88 100644 --- 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_info *mtd, loff_t to, size_t len, 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; -- 2.15.0