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Diffstat (limited to 'src/tools')
| -rw-r--r-- | src/tools/qemu.md | 165 |
1 files changed, 136 insertions, 29 deletions
diff --git a/src/tools/qemu.md b/src/tools/qemu.md index 8a48bdc..e591cec 100644 --- a/src/tools/qemu.md +++ b/src/tools/qemu.md @@ -23,43 +23,70 @@ Ctrl+a c switch between monitor and console ## VM config snippet Following command-line gives a good starting point to assemble a VM: -```bash -qemu-system-x86_64 \ - -cpu host -enable-kvm -smp 4 \ - -m 8G \ - -vga virtio -display sdl,gl=on \ - -boot menu=on \ - -cdrom <iso> \ - -hda <disk> \ - -device qemu-xhci,id=xhci \ - -device usb-host,bus=xhci.0,vendorid=0x05e1,productid=0x0408,id=capture-card +``` +qemu-system-x86_64 \ + -cpu host -enable-kvm -smp 4 \ + -m 8G \ + -vga virtio -display sdl,gl=on \ + -boot menu=on \ + -cdrom <iso> \ + -hda <disk> \ + -device qemu-xhci,id=xhci \ + -device usb-host,bus=xhci.0,vendorid=0x05e1,productid=0x0408,id=capture-card ``` ### CPU & RAM -- `-cpu host` emulate host CPU in guest VM -- `-enable-kvm` use KVM instead software models (requires KVM on host machine) -- `-smp <N>` number of guest CPUs -> List available CPUs `qemu-system-x86_64 -cpu help`. +```bash +# Emulate host CPU in guest VM, enabling all supported host featured (requires KVM). +# List available CPUs `qemu-system-x86_64 -cpu help`. +-cpu host + +# Enable KVM instead software emulation. +-enable-kvm -- `-m 8G` size of guest RAM +# Configure number of guest CPUs. +-smp <N> + +# Configure size of guest RAM. +-m 8G +``` ### Graphic & Display -- `-vga virtio` use virtio as 3D video graphic accelerator (requires virgl in guest) -- `-display sdl,gl=on` use sdl window and enable openGL context +```bash +# Use sdl window as display and enable openGL context. +-display sdl,gl=on + +# Use vnc server as display (eg on display `:42` here). +-display vnc=localhost:42 + +# Confifure virtio as 3D video graphic accelerator (requires virgl in guest). +-vga virtio +``` ### Boot Menu -- `-boot menu=on` enables boot menu to select boot device (enter with `ESC`) +```bash +# Enables boot menu to select boot device (enter with `ESC`). +-boot menu=on +``` ### Block devices -- `-cdrom <iso>` attach cdrom drive with iso to a VM -- `-hda <disk>` attach disk drive to a VM -- `-drive file=<file>,format=qcow2` generic way to configure & attach a drive to a VM +```bash +# Attach cdrom drive with iso to a VM. +-cdrom <iso> + +# Attach disk drive to a VM. +-hda <disk> + +# Generic way to configure & attach a drive to a VM. +-drive file=<file>,format=qcow2 +``` #### Create a disk with [`qemu-img`][doc-qemu-img] + To create a `qcow2` disk (qemu copy-on-write) of size `10G`: ```bash qemu-img create -f qcow2 disk.qcow2 10G @@ -87,26 +114,106 @@ lsblk -f /dev/sda ``` ### USB - #### Host Controller -- `-device qemu-xhci,id=xhci` add XHCI USB controller to the VM (supports USB 3.0, 2.0, 1.1). `id=xhci` creates a usb bus named `xhci`. + +```bash +# Add XHCI USB controller to the VM (supports USB 3.0, 2.0, 1.1). +# `id=xhci` creates a usb bus named `xhci`. +-device qemu-xhci,id=xhci +``` #### USB Device -- `-device usb-host,bus=xhci.0,vendorid=0x05e1,productid=0x0408` pass-through USB device from host identified by vendorid & productid and attach to usb bus `xhci.0` (defined with controller `id`) + +```bash +# Pass-through USB device from host identified by vendorid & productid and +# attach to usb bus `xhci.0` (defined with controller `id`). +-device usb-host,bus=xhci.0,vendorid=0x05e1,productid=0x0408 +``` ## Debugging -- `-gdb tcp::<port>` open gdbstub on tcp `<port>` (`-s` shorthand for `-gdb tcp::1234`). -- `-S` freeze CPU at startup. +```bash +# Open gdbstub on tcp `<port>` (`-s` shorthand for `-gdb tcp::1234`). +-gdb tcp::<port> + +# Freeze guest CPU at startup and wait for debugger connection. +-S +``` + +## IO redirection + +```bash +# Create raw tcp server for `serial IO` and wait until a client connects +# before executing the guest. +-serial tcp:localhost:12345,server,wait + +# Create telnet server for `serial IO` and wait until a client connects +# before executing the guest. +-serial telnet:localhost:12345,server,wait + +# Configure redirection for the QEMU `mointor`, arguments similar to `-serial` +# above. +-monitor ... +``` +> In `server` mode use `nowait` to execute guest without waiting for a client +> connection. + +## Network + +```bash +# Redirect host tcp port `1234` to guest port `4321`. +-nic user,hostfwd=tcp:localhost:1234-:4321 +``` + +## Shared drives + +```bash +# Attach a `virtio-9p-pci` device to the VM. +# The guest requires 9p support and can mount the shared drive as: +# mount -t 9p -o trans=virtio someName /mnt +-virtfs local,id=someName,path=<someHostPath>,mount_tag=someName,security_model=none +``` + +## Tracing + +```bash +# List name of all trace points. +-trace help + +# Enable trace points matching pattern and optionally write trace to file. +-trace <pattern>[,file=<file>] + +# Enable trace points for all events listed in the <events> file. +# File must contain one event/pattern per line. +-trace events=<events> +``` + +## Appendix: Direct `Kernel` boot + +Example command line to directly boot a `Kernel` with an `initrd` ramdisk. +```bash +qemu-system-x86_64 \ + -cpu host \ + -enable-kvm \ + -kernel <dir>/arch/x86/boot/bzImage \ + -append "earlyprintk=ttyS0 console=ttyS0 nokaslr init=/init debug" \ + -initrd <dir>/initramfs.cpio.gz \ + ... +``` +Instructions to build a minimal [`Kernel` and `initrd`][blog-qemu-dbg]. ## References + - [QEMU USB][doc-qemu-usb] - [QEMU IMG][doc-qemu-img] - [QEMU Tools][doc-qemu-tools] - [QEMU System][doc-qemu-system] +- [QEMU Invocation (command line args)][doc-qemu-invocation] [doc-qemu-usb]: https://github.com/qemu/qemu/blob/master/docs/usb2.txt -[doc-qemu-img]: https://qemu.readthedocs.io/en/latest/tools/qemu-img.html -[doc-qemu-tools]: https://qemu.readthedocs.io/en/latest/tools/index.html -[doc-qemu-system]: https://www.qemu.org/docs/master/system/index.html +[doc-qemu-img]: https://qemu-project.gitlab.io/qemu/tools/qemu-img.html +[doc-qemu-tools]: https://qemu-project.gitlab.io/qemu/tools/index.html +[doc-qemu-system]: https://qemu-project.gitlab.io/qemu/system/index.html +[doc-qemu-invocation]: https://qemu-project.gitlab.io/qemu/system/invocation.html +[blog-qemu-dbg]: https://blog.memzero.de/kernel-debugging-qemu |