Commit c27e9b80 authored by Sebastian Siewior's avatar Sebastian Siewior Committed by David Woodhouse
Browse files

[MTD] [NAND] fix possible Ooops in rfc_from4 



I found this while I was looking how the rs_lib is working.  The rs_decoder is
initialized _after_ the nand core code read the BBT table and _after_ the
partition table has been added.  The driver has a private BBT description
which is in located in flash data so we Ooops if there is a bit flip _or_ if a
bit flips while reading the partition table.

This patch moves the initialization of the rs_lib before the first possible
access by nand core.

Signed-off-by: default avatarSebastian Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jörn Engel <joern@wh.fh-wedel.de>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarDavid Woodhouse <dwmw2@infradead.org>
parent cb53b3b9

drivers/mtd/nand/rtc_from4.c

+29 −21
Original line number Diff line number Diff line
@@ -478,6 +478,7 @@ static int __init rtc_from4_init(void) 
	struct nand_chip *this;

	unsigned short bcr1, bcr2, wcr2;

	int i;

	int ret;



	/* Allocate memory for MTD device structure and private data */

	rtc_from4_mtd = kmalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip), GFP_KERNEL);
@@ -537,6 +538,22 @@ static int __init rtc_from4_init(void) 
	this->ecc.hwctl = rtc_from4_enable_hwecc;

	this->ecc.calculate = rtc_from4_calculate_ecc;

	this->ecc.correct = rtc_from4_correct_data;



	/* We could create the decoder on demand, if memory is a concern.

	 * This way we have it handy, if an error happens

	 *

	 * Symbolsize is 10 (bits)

	 * Primitve polynomial is x^10+x^3+1

	 * first consecutive root is 0

	 * primitve element to generate roots = 1

	 * generator polinomial degree = 6

	 */

	rs_decoder = init_rs(10, 0x409, 0, 1, 6);

	if (!rs_decoder) {

		printk(KERN_ERR "Could not create a RS decoder\n");

		ret = -ENOMEM;

		goto err_1;

	}

#else

	printk(KERN_INFO "rtc_from4_init: using software ECC detection.\n");
@@ -549,8 +566,8 @@ static int __init rtc_from4_init(void) 


	/* Scan to find existence of the device */

	if (nand_scan(rtc_from4_mtd, RTC_FROM4_MAX_CHIPS)) {

		kfree(rtc_from4_mtd);

		return -ENXIO;

		ret = -ENXIO;

		goto err_2;

	}



	/* Perform 'device recovery' for each chip in case there was a power loss. */
@@ -566,28 +583,19 @@ static int __init rtc_from4_init(void) 
#endif



	/* Register the partitions */

	add_mtd_partitions(rtc_from4_mtd, partition_info, NUM_PARTITIONS);

	ret = add_mtd_partitions(rtc_from4_mtd, partition_info, NUM_PARTITIONS);

	if (ret)

		goto err_3;



#ifdef RTC_FROM4_HWECC

	/* We could create the decoder on demand, if memory is a concern.

	 * This way we have it handy, if an error happens

	 *

	 * Symbolsize is 10 (bits)

	 * Primitve polynomial is x^10+x^3+1

	 * first consecutive root is 0

	 * primitve element to generate roots = 1

	 * generator polinomial degree = 6

	 */

	rs_decoder = init_rs(10, 0x409, 0, 1, 6);

	if (!rs_decoder) {

		printk(KERN_ERR "Could not create a RS decoder\n");

		nand_release(rtc_from4_mtd);

		kfree(rtc_from4_mtd);

		return -ENOMEM;

	}

#endif

	/* Return happy */

	return 0;

err_3:

	nand_release(rtc_from4_mtd);

err_2:

	free_rs(rs_decoder);

err_1:

	kfree(rtc_from4_mtd);

	return ret;

}



module_init(rtc_from4_init);

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