From c27e9b80bee039cfefa51c7af08b01eaab3dfb61 Mon Sep 17 00:00:00 2001 From: Sebastian Siewior Date: Fri, 18 Apr 2008 13:44:24 -0700 Subject: [PATCH] [MTD] [NAND] fix possible Ooops in rfc_from4 MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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: Sebastian Siewior Cc: Thomas Gleixner Cc: Jörn Engel Signed-off-by: Andrew Morton Signed-off-by: David Woodhouse --- drivers/mtd/nand/rtc_from4.c | 50 +++++++++++++++++++++--------------- 1 file changed, 29 insertions(+), 21 deletions(-) diff --git a/drivers/mtd/nand/rtc_from4.c b/drivers/mtd/nand/rtc_from4.c index 0f6ac250f4..26f88215bc 100644 --- a/drivers/mtd/nand/rtc_from4.c +++ b/drivers/mtd/nand/rtc_from4.c @@ -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); -- 2.39.5