Workaround: Blank screen after boot Backtrack 4 R2.

Some people are experiencing problems while booting Backtrack 4 R2, they either get a blank screen and freeze or an error message when booting in "Text Mode" similar to this one:

Code:

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[<c05e3004>] ? acpi_os_release_object+0xd/0x11
[<c06030f8>] ? acpi_ut_update_object_reference+0xb1/0x116
[<c05fb4a9>] acpi_get_handle+0x6c/0x85
[<c09fa444>] acpi_gts_bfs_check+0x16/0x5c
[<c04519ba>] ? register_reboot_notifier+0x14/0x16
[<c09fa5c9>] acpi_sleep_init+0x13f/0x14a
[<c09fa810>] acpi_init+0x112/0x2c8
[<c09fa6fe>] ? acpi_init+0x0/0x2c8
[<c0401143>] do_one_initcall+0x51/0x13f
[<c09d43f2>] kernel_init+0x197/0x218
[<c09d425b>] ? kernel_init+0x0/0x218
[<c04039be>] kernel_tread_helper+0x6/0x10

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So the main problem is the kernel can not find ACPI support.
This is a kernel bug (80%) but I could be wrong, so if anyone can add more information or another workaround/fix please feel free to do so.

Currently there are 2 workarounds for this issue:

1. Revert back to the previous kernel 2.6.34: (RECOMMENDED SOLUTION)
*You do this by installing a fresh R1, after that you upgrade all tools except the kernel.
*This works just fine, all tools are working, and you should now have problems with injection either, if it was supported in R1.

2. Boot with "noapic acpi=off" flags:
*Now first before trying this you should take a look at what these two actually do:
Advanced Configuration and Power Interface - Wikipedia, the free encyclopedia
Advanced Programmable Interrupt Controller - Wikipedia, the free encyclopedia

You can also use Google for more info.

How to do this:

*Plug in the LiveCD and when you enter grub, hit the "e" key:

http://img404.imageshack.us/img404/3610/56911035.png

*After that select the "kernel" and hit "e" key again:

http://img121.imageshack.us/img121/4866/58646563.png

*Type in the "noapic acpi=off" flags (without quotes ofc.) after that hit "Enter" and "b" to boot.

http://img543.imageshack.us/img543/5194/66221724.png

Now Backtrack should boot.

If you want to install it on a HDD or Persistent USB, remember to continue using the live cd, mount the /boot/grub/ partition and add "noapic acpi=off" to the menu.lst

From here on it all depends if you're hardware is completely ACPI dependent or not.

Turning ACPI off might:
- Kill the CPU cores and leave only 1 enabled
- Turn off cooling fans
- No battery support (laptops)

As I said this depends on your hardwares ACPI dependency.

If you choose to run with "noapic acpi=off" I suggest, you check the cooling fans if they work and install lm-sensors for CPU temp support.

Another known issue is the power off one, you won't be able to power off, however if you log out of X and type in:

Code:

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shutdown -h 0

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You will see it is killing all running processes, stopping HDDs and then give you a message similar to:

Code:

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System halted

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From this message you can just hit the power off button and it should turn off.


If your hardware is not ACPI dependent you should be able to run without any problems but I suggest you check the CPU temp using lm-sensors from time to time just to make sure.

IF YOU ARE NOT SURE ABOUT WHAT YOU ARE DOING I JUST WANT YOU TO KNOW THAT I AM NOT RESPONSIBLE FOR ANY HARDWARE DAMAGE THAT MIGHT OCCUR !!!!

the noapic acpi=off solution did not work out for me, the OS never got to loading after selecting that kernel boot line from grub so I decided to do a reinstall of R1 and just upgrade the tools.

Got R2 running smooth on my laptop though so I guess this issue might be related to only certain pieces of hardware?

Noone of 2 solutions have worked for me......anything else?? :/

Quote:

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Originally Posted by sav2003

Noone of 2 solutions have worked for me......anything else?? :/

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Than it could be that your hardware is not compatible. I suggest you run it inside a Virtual Environment.