Documentation: Reorganize the build documentation

1 files changed, 32 insertions, 5 deletions

diff --git a/Documentation/Troubleshooting.md b/Documentation/Troubleshooting.md
index 4995a1dbd1..752f24f7c1 100644
--- a/Documentation/Troubleshooting.md
+++ b/Documentation/Troubleshooting.md
@@ -2,18 +2,45 @@
 
 In case of an error, you might find an answer of how to deal it here.
 
-## I build everything, the VM starts and then I see...
+## Building SerenityOS
 
-### "Error: Kernel Image too big for memory slot. Halting!"
+### CMake fails to configure the build because it's outdated
+
+Ensure your CMake version is >= 3.16 with `cmake --version`. If your system doesn't provide a suitable
+version of CMake, you can download a binary release from the [CMake website](https://cmake.org/download).
+
+### QEMU is missing or is outdated
+
+Ensure your [QEMU](https://www.qemu.org/) version is >= 5 with `qemu-system-i386 -version`. Otherwise,
+install it. You can also build it using the `Toolchain/BuildQemu.sh` script.
+
+### GCC is missing or is outdated
+
+Ensure your gcc version is >= 10 with `gcc --version`. Otherwise, install it. If your gcc binary is not
+called `gcc` you have to specify the names of your C and C++ compiler when you run cmake, e.g.
+`cmake ../.. -GNinja -DCMAKE_C_COMPILER=gcc-11 -DCMAKE_CXX_COMPILER=g++-11`.
+
+## Running SerenityOS
+
+### The VM is really slow
+
+On Linux, QEMU is significantly faster if it's able to use KVM. The run script will automatically enable KVM
+if `/dev/kvm` exists and is readable+writable by the current user. On Windows, ensure that you have
+WHPX acceleration enabled.
+
+### Boot fails with "Error: Kernel Image too big for memory slot. Halting!"
 
 This means the kernel is too large again. Contact us on the discord server or open a GitHub Issue about it.
 You might want to revert latest changes in tree to see if that solves the problem temporarily.
 
-### "Your computer does not support long mode (64-bit mode). Halting!"
+### Boot fails with "Your computer does not support long mode (64-bit mode). Halting!"
+
+Either your machine (if you try to boot on bare metal) is very old, thus it's not supporting x86_64
+extensions, or you try to use VirtualBox without using a x64 virtualization mode or you try to use
+`qemu-system-i386` which doesn't support x86_64 extensions too.
 
-Either your machine (if you try to boot on bare metal) is very old, thus it's not supporting x86_64 extensions, or you try to use VirtualBox without using a x64 virtualization mode or you try to use `qemu-system-i386` which doesn't support x86_64 extensions too.
+### Boot fails with "Your computer does not support PAE. Halting!"
 
-### "Your computer does not support PAE. Halting!"
 - If booting on bare metal, your CPU is too old to boot Serenity.
 - If you're using VirtualBox, you need to enable PAE/NX. Check the instructions [here.](VirtualBox.md)
 - If you're using QEMU, the [CPU model configuration](https://qemu-project.gitlab.io/qemu/system/qemu-cpu-models.html) is not exposing PAE.