How can I view and change the kernel bootargs my Nexus 7 is using at startup?

Question

In the event that a user wants to make modifications to the kernel commandline how would I do so? Can I "cat /proc/cmdline" to view the bootargs??

Answer 1

/proc/cmdline will give you the current boot arguments but also reveal a lot of data that's not technically modifiable.

I would recommend using: sudo abootimg -i /dev/mmcblk0p2

Which should give you similar output:

ubuntu@nexus7-265143b8:~$ sudo abootimg -i /dev/mmcblk0p2 

Android Boot Image Info:

* file name = /dev/mmcblk0p2 [block device]

* image size = 8388608 bytes (8.00 MB)
  page size  = 2048 bytes

* Boot Name = ""

* kernel size       = 4522232 bytes (4.31 MB)
  ramdisk size      = 2182999 bytes (2.08 MB)

* load addresses:
  kernel:       0x10008000
  ramdisk:      0x11000000
  tags:         0x10000100

* cmdline = root=/dev/mmcblk0p9 ro console=tty1 fbcon=rotate:1 quiet

* id = 0x00000000 0x00000000 0x00000000 0x00000000 0x00000000 0x00000000 0x00000000 0x00000000  

To modify your cmdline arguments issue the following command:

sudo abootimg -u /dev/mmcblk0p2 -c cmdline ='foo bar baz'