[PATCH 1/1] mtd: nand: add check for out of page read
Jason Liu
liu.h.jason at gmail.com
Thu Dec 23 01:06:33 EST 2010
Hi, Artem,
2010/12/20 Artem Bityutskiy <dedekind1 at gmail.com>:
> On Wed, 2010-12-15 at 09:55 +0800, Jason Liu wrote:
>> > /* Do not allow reads past end of device */
>> > if (unlikely(from >= mtd->size ||
>> > ops->ooboffs + readlen > ((mtd->size >> chip->page_shift) -
>> > (from >> chip->page_shift)) * len)) {
>> > DEBUG(MTD_DEBUG_LEVEL0, "%s: Attempt read beyond end "
>> > "of device\n", __func__);
>> > return -EINVAL;
>> > }
>>
>> Here the mtd->size in nand_base.c should be the NAND flash chip size,
>
> I think this is partition size as well.
I think you are wrong. This should be the NAND flash chip size not the
partition size.
>
>> while in nand_oobtest,
>>
>> /* Attempt to read off end of device */
>> ops.mode = MTD_OOB_AUTO;
>> ops.len = 0;
>> ops.retlen = 0;
>> ops.ooblen = mtd->ecclayout->oobavail;
>> ops.oobretlen = 0;
>> ops.ooboffs = 1;
>> ops.datbuf = NULL;
>> ops.oobbuf = readbuf;
>> printk(PRINT_PREF "attempting to read past end of device\n");
>> printk(PRINT_PREF "an error is expected...\n");
>> err = mtd->read_oob(mtd, mtd->size - mtd->writesize, &ops);
>> if (err) {
>> printk(PRINT_PREF "error occurred as expected\n");
>> err = 0;
>> } else {
>> printk(PRINT_PREF "error: read past end of device\n");
>> errcnt += 1;
>> }
>> }
>>
>> here, mtd->size is mtd partition size right? when the mtd partition is
>> not the last MTD partition, the error will happen.
>
> I think this is the same in both. Try to debug this with printks().
>
>>
>> I have tested on real NAND, while not on nandsim.
>
> Please, try to reproduce this with nandsim as well, and if it works, try
> to find out why (using printk debugging)
Yes, I have reproduce this issue with nandsim, please check the following log,
root at freescale ~$ insmod nandsim.ko first_id_byte=0x20
second_id_byte=0xaa third_id_byte=0x00 fourth_id_byte=0x15
parts=0x400,0x400
[nandsim] warning: read_byte: unexpected data output cycle, state is
STATE_READY return 0x0
[nandsim] warning: read_byte: unexpected data output cycle, state is
STATE_READY return 0x0
[nandsim] warning: read_byte: unexpected data output cycle, state is
STATE_READY return 0x0
[nandsim] warning: read_byte: unexpected data output cycle, state is
STATE_READY return 0x0
NAND device: Manufacturer ID: 0x20, Chip ID: 0xaa (ST Micro NAND
256MiB 1,8V 8-bit)
flash size: 256 MiB
page size: 2048 bytes
OOB area size: 64 bytes
sector size: 128 KiB
pages number: 131072
pages per sector: 64
bus width: 8
bits in sector size: 17
bits in page size: 11
bits in OOB size: 6
flash size with OOB: 270336 KiB
page address bytes: 5
sector address bytes: 3
options: 0x8
Scanning device for bad blocks
Creating 2 MTD partitions on "NAND 256MiB 1,8V 8-bit":
0x000000000000-0x000008000000 : "NAND simulator partition 0"
0x000008000000-0x000010000000 : "NAND simulator partition 1"
root at freescale ~$ cat /proc/mtd
dev: size erasesize name
mtd0: 00300000 00080000 "bootloader"
mtd1: 00500000 00080000 "nand.kernel"
mtd2: 10000000 00080000 "nand.rootfs"
mtd3: 10000000 00080000 "nand.userfs1"
mtd4: df800000 00080000 "nand.userfs2"
mtd5: 08000000 00020000 "NAND simulator partition 0"
mtd6: 08000000 00020000 "NAND simulator partition 1"
root at freescale ~$ insmod mtd_oobtest.ko dev=5
=================================================
mtd_oobtest: MTD device: 5
mtd_oobtest: MTD device size 134217728, eraseblock size 131072, page
size 2048, count of eraseblocks 1024, pages per eraseblock
64, OOB size 64
mtd_oobtest: scanning for bad eraseblocks
mtd_oobtest: scanned 1024 eraseblocks, 0 are bad
mtd_oobtest: test 1 of 5
mtd_oobtest: erasing whole device
mtd_oobtest: erased 1024 eraseblocks
mtd_oobtest: writing OOBs of whole device
mtd_oobtest: written up to eraseblock 0
mtd_oobtest: written up to eraseblock 256
mtd_oobtest: written up to eraseblock 512
mtd_oobtest: written up to eraseblock 768
mtd_oobtest: written 1024 eraseblocks
mtd_oobtest: verifying all eraseblocks
mtd_oobtest: verified up to eraseblock 0
mtd_oobtest: verified up to eraseblock 256
mtd_oobtest: verified up to eraseblock 512
mtd_oobtest: verified up to eraseblock 768
mtd_oobtest: verified 1024 eraseblocks
mtd_oobtest: test 2 of 5
mtd_oobtest: erasing whole device
mtd_oobtest: erased 1024 eraseblocks
mtd_oobtest: writing OOBs of whole device
mtd_oobtest: written up to eraseblock 0
mtd_oobtest: written up to eraseblock 256
mtd_oobtest: written up to eraseblock 512
mtd_oobtest: written up to eraseblock 768
mtd_oobtest: written 1024 eraseblocks
mtd_oobtest: verifying all eraseblocks
mtd_oobtest: verified up to eraseblock 0
mtd_oobtest: verified up to eraseblock 256
mtd_oobtest: verified up to eraseblock 512
mtd_oobtest: verified up to eraseblock 768
mtd_oobtest: verified 1024 eraseblocks
mtd_oobtest: test 3 of 5
mtd_oobtest: erasing whole device
mtd_oobtest: erased 1024 eraseblocks
mtd_oobtest: writing OOBs of whole device
mtd_oobtest: written up to eraseblock 0
mtd_oobtest: written up to eraseblock 256
mtd_oobtest: written up to eraseblock 512
mtd_oobtest: written up to eraseblock 768
mtd_oobtest: written 1024 eraseblocks
mtd_oobtest: verifying all eraseblocks
mtd_oobtest: verified up to eraseblock 0
mtd_oobtest: verified up to eraseblock 256
mtd_oobtest: verified up to eraseblock 512
mtd_oobtest: verified up to eraseblock 768
mtd_oobtest: verified 1024 eraseblocks
mtd_oobtest: test 4 of 5
mtd_oobtest: erasing whole device
mtd_oobtest: erased 1024 eraseblocks
mtd_oobtest: attempting to start write past end of OOB
mtd_oobtest: an error is expected...
mtd_oobtest: error occurred as expected
mtd_oobtest: attempting to start read past end of OOB
mtd_oobtest: an error is expected...
mtd_oobtest: error occurred as expected
mtd_oobtest: attempting to write past end of device
mtd_oobtest: an error is expected...
mtd_oobtest: error occurred as expected
mtd_oobtest: attempting to read past end of device
mtd_oobtest: an error is expected...
mtd_oobtest: error: read past end of device
mtd_oobtest: attempting to write past end of device
mtd_oobtest: an error is expected...
mtd_oobtest: error occurred as expected
mtd_oobtest: attempting to read past end of device
mtd_oobtest: an error is expected...
mtd_oobtest: error: read past end of device
mtd_oobtest: test 5 of 5
mtd_oobtest: erasing whole device
mtd_oobtest: erased 1024 eraseblocks
mtd_oobtest: writing OOBs of whole device
mtd_oobtest: written up to eraseblock 0
mtd_oobtest: written up to eraseblock 0
mtd_oobtest: written up to eraseblock 256
mtd_oobtest: written up to eraseblock 256
mtd_oobtest: written up to eraseblock 512
mtd_oobtest: written up to eraseblock 512
mtd_oobtest: written up to eraseblock 768
mtd_oobtest: written up to eraseblock 768
mtd_oobtest: written 1023 eraseblocks
mtd_oobtest: verifying all eraseblocks
mtd_oobtest: verified up to eraseblock 0
mtd_oobtest: verified up to eraseblock 256
mtd_oobtest: verified up to eraseblock 512
mtd_oobtest: verified up to eraseblock 768
mtd_oobtest: verified 1023 eraseblocks
mtd_oobtest: finished with 2 errors
=================================================
>
> --
> Best Regards,
> Artem Bityutskiy (Битюцкий Артём)
>
>
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