semantic: 0.137 boot: 0.120 other: 0.118 device: 0.102 files: 0.080 permissions: 0.067 performance: 0.064 graphic: 0.064 PID: 0.058 socket: 0.054 vnc: 0.048 network: 0.040 debug: 0.028 KVM: 0.021 debug: 0.407 files: 0.126 boot: 0.120 PID: 0.059 device: 0.053 other: 0.045 socket: 0.036 network: 0.033 performance: 0.033 semantic: 0.031 vnc: 0.020 graphic: 0.013 permissions: 0.013 KVM: 0.013 qemu arm no longer able to boot RPI Kernels Since RPi Kernel 1.20170427, qemu is no longer able to emulate the Rasberry Pi, as the linux kernel is complaining about timing issues. Old kernel output - https://pastebin.com/wvkneNNF New kernel output - https://pastebin.com/QTwgCkV2 Note that the actual error is caused by the kernel being unable to get the timing source for the mmc (Line 160), which causes an unable-to-mount-root panic. There are other issues with the serial port returning an invalid speed, which displays a divide-by-zero error, which is PROBABLY a symptom of the same root cause. This is simple to replicate - The last working kernel is available here: https://github.com/raspberrypi/firmware/tree/1.20170405/boot Download kernel7 and the dtb, and try to boot with (for example) qemu-system-aarch64 -M raspi2 -kernel kernel7.img -dtb bcm2709-rpi-2-b.dtb -serial stdio -sd noobs.img -append "root=/dev/mmcblk0p2 init=/bin/bash" This works, and boots successfully. However, if you replace the kernel7.img and dtb with ones taken from https://github.com/raspberrypi/firmware/tree/1.20170427/boot it will NOT boot because of various clock timing issues (as in the second paste) Isn't this likely due to the newer kernel accessing hardware we are not emulating properly? On 19 October 2018 at 12:59, Alex Bennée