[techie001]

Hello, my Dlink dir-880L A2 was running r34929 perfectly for around 5 months until we experienced intermittent power failures (I've since bought a UPS!). Since then, it simply boot loops. Orange light powers on, after about 20 secs all lights flash then the sequence starts over. I was able to use recovery and tried reinstalling various versions of DD-WRT. All the same result. Finally, I purchased a USB/TTL cable and was able to capture the boot log. Sure, enough it's getting a kernel panic and reboots after maybe 20-30 secs. It should be noted that the stock firmware seems to work fine. I'm only seeing the boot loop with dd wrt.

So here's my summary of what is failing and I'm not sure if this is the result of a block of bad memory that now affects dd wrt's root partition? Any help you can profile would be great appreciated!

It appears that mtdblock2 does not exist and this apparently is the selected "root=" boot partition chosen by dd wrt. Below is a snippet of the boot log I was able to capture using serial terminal.


Northstar brcmnand NAND Flash Controller driver, Version 0.1 (c) Broadcom Inc. 2012
nand: device found, Manufacturer ID: 0x01, Chip ID: 0xf1
nand: AMD/Spansion NAND 128MiB 3,3V 8-bit
nand: 128 MiB, SLC, erase size: 128 KiB, page size: 2048, OOB size: 64
Spare area=64 eccbytes 8, ecc bytes located at:
14 15 30 31 46 47 62 63
Available 55 bytes at (off,len):
(1,13) (16,14) (32,14) (48,14) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0) (0,0)
Scanning device for bad blocks
Bad eraseblock 948 at 0x000007680000
Bad eraseblock 949 at 0x0000076a0000
Bad eraseblock 954 at 0x000007740000
Bad eraseblock 1020 at 0x000007f80000
Options: NO_SUBPAGE_WRITE,
Creating 1 MTD partitions on "brcmnand":
0x000000000000-0x000008000000 : "ddwrt"
blk_update_request: I/O error, dev mtdblock2, sector 0
SQUASHFS error: squashfs_read_data failed to read block 0x0
squashfs: SQUASHFS error: unable to read squashfs_super_block
VFS: Cannot open root device "1f02" or unknown-block(31,2): error -5
Please append a correct "root=" boot option; here are the available partitions:
0100 4096 ram0 (driver?)
0101 4096 ram1 (driver?)
0102 4096 ram2 (driver?)
0103 4096 ram3 (driver?)
0104 4096 ram4 (driver?)
0105 4096 ram5 (driver?)
0106 4096 ram6 (driver?)
0107 4096 ram7 (driver?)
0108 4096 ram8 (driver?)
0109 4096 ram9 (driver?)
010a 4096 ram10 (driver?)
010b 4096 ram11 (driver?)
010c 4096 ram12 (driver?)
010d 4096 ram13 (driver?)
010e 4096 ram14 (driver?)
010f 4096 ram15 (driver?)
1f00 4096 mtdblock0 (driver?)
1f01 4032 mtdblock1 (driver?)
1f03 64 mtdblock3 (driver?)
1f04 64 mtdblock4 (driver?)
1f05 131072 mtdblock5 (driver?)
1f06 131072 mtdblock6 (driver?)
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(31,2)
CPU0: stopping
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.4.151-rc1 #3733
Hardware name: Northstar Prototype
Backtrace:
Function entered at [<80019bf4>] from [<80019f78>]
r7:803aff28 r6:60000193 r5:00000000 r4:803ce0a0
Function entered at [<80019f60>] from [<80131dcc>]
Function entered at [<80131d48>] from [<8001bc98>]
r7:803aff28 r6:00000000 r5:803e11a0 r4:00000000
Function entered at [<8001bba0>] from [<80009370>]
r7:b0101100 r6:803aff28 r5:803bdb18 r4:b0100100
Function entered at [<800092fc>] from [<80009e80>]
Exception stack(0x803aff28 to 0x803aff70)
ff20: 86dd424c 86dd424c 00000000 8000a960 803bd8e0 ffffffff
ff40: 803bd800 803e1020 803818c8 803e101c 00000000 803aff84 803aff88 803aff78
ff60: 80017ad0 80017ac0 60000013 ffffffff
r7:803aff5c r6:ffffffff r5:60000013 r4:80017ac0
Function entered at [<80017a9c>] from [<80061e7c>]
Function entered at [<80061e4c>] from [<80061fb4>]
Function entered at [<80061e80>] from [<800129a4>]
Function entered at [<80012938>] from [<80360ba8>]
Function entered at [<803608e0>] from [<0000807c>]
r9:413fc090 r8:0000406a r7:803c3d94 r6:803818c4 r5:803bd860 r4:803e1090
Rebooting in 10 seconds..