Introduces a SERENITY_QEMU_CPU environment variable that allows
overriding of the qemu -cpu command line parameter. If not specified,
the argument defaults to "max".
The primary motivation behind this is to be able to enable or disable
specific features for the vCPU in order to workaround QEMU issues with
certain hardware accelerators. For example, QEMU on Windows with WPHX
sometimes fails to start unless Virtual Machine eXtensions are
disabled. This can now be done with:
export SERENITY_QEMU_CPU="max,vmx=off"
If SERENITY_BUILD is not set or empty, SERENITY_BUILD is treated as if
it was set to '.'.
`run.sh` will cd to SERENITY_BUILD before running the emulator.
Also, export SERENITY_BUILD in `Meta/CLion/run.sh` since we are using it
in `Meta/run.sh`.
Also, allow using a different bochs configuration file by setting the
SERENITY_BOCHSRC variable.
The run script is not in Kernel/ anymore, let's move `.bochsrc` in Meta/
so that it can be used with the new build system.
Also make bochs use `grub_disk_image` instead of `_disk_image`
run.sh currently makes qemu print this as the very first output:
WARNING: Image format was not specified for '_disk_image' and probing guessed raw.
Automatically detecting the format is dangerous for raw images, write operations on block 0 will be restricted.
Specify the 'raw' format explicitly to remove the restrictions.
This is scary for people who don't know that this is normal, and
write operations to block 0 being restricted could be confusing
for some operations happening from within serenity too at some point.
So specify the 'raw' format explicitly, like the warning suggests.
Requires using -drive instead of -hda.
From `man qemu-system`:
Instead of -hda, -hdb, -hdc, -hdd, you can use:
qemu-system-x86_64 -drive file=file,index=0,media=disk
So use that, and also pass format=raw.
