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ARM ChromeOS Meltdown Anonymous 03/25/2018 (Sun) 17:35:05 [Preview] No. 12529
>Meltdown only affects Inte-

Dumping this info here since /g/ is full of bait threads and shit.

This is what meltdown looks like in a Samsung Chromebook Plus. If you want to give it a try yourself, start by installing Arch on a USB stick

https://archlinuxarm.org/platforms/armv8/rockchip/samsung-chromebook-plus

And then,

$git clone https://github.com/lgeek/spec_poc_arm.git
$cd spec_poc_arm
$make
$taskset 0x30 ./dump_sys_regs

To pin the task to the vulnerable A72 cores use 0x30, use 0x0F to compare with the not vulnerable A53 cores.

Meltdown patches are not being backported to kernel 4.4. Meltdown mitigation also requires firmware patch. Google will not do any of this for Chromebook users. 4.4.110 is from Jan 5 when meltdown patches were going out for Intel. Google is addressing Meltdown for Intel only.

http://kroah.com/log/blog/2018/01/06/meltdown-status/

Your only secure option is going to be to ditch Google Chrome OS and upgrade to mainline kernel. You also need a firmware patch, so that means flashing your own build of firmware with flashrom.

https://github.com/ARM-software/arm-trusted-firmware

https://youtube.com/watch?v=z-KpAA4_afs [Embed]

https://www.chromium.org/chromium-os/developer-information-for-chrome-os-devices/custom-firmware

Your GPU will never work on mainline, because the userspace mali drivers target 4.4 and as mentioned, Google will not be backporting patches. Reverse engineering needed here,

https://github.com/rockchip-linux/libmali

TL;DR: Google is passing off known defective OS and firmware as new and secure with no intention of ever fixing the issues.


Anonymous 03/25/2018 (Sun) 17:38:46 [Preview] No.12530 del


Anonymous 04/15/2018 (Sun) 16:51:53 [Preview] No.12643 del
Running mainline kernel is now much easier.

https://archlinuxarm.org/platforms/armv8/rockchip/samsung-chromebook-plus

Mainline Kernel
The installation above will use the ChromeOS 4.4 kernel. The mainline kernel can be used instead, though some hardware may not be working yet.

Install linux-aarch64 packages, replacing the linux-gru package:
pacman -S linux-aarch64 linux-aarch64-chromebook
Type y and hit enter when prompted to flash the kernel to the kernel partition.
Reboot.


Anonymous 04/15/2018 (Sun) 16:54:13 [Preview] No.12644 del
The spectre/meltdown test still shows A72 cores are vulnerable under mainline kernel. Flashing firmware will require opening the device and removing the write protect screw on the bios.



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