On 2024-11-01 10:49:36-0400, Tamir Duberstein wrote: > On Fri, Nov 1, 2024, 09:52 Alyssa Ross <hi@xxxxxxxxx> wrote: > > > > On Fri, Oct 25, 2024 at 05:03:54PM -0400, Tamir Duberstein wrote: > > > @@ -124,6 +125,29 @@ class LinuxSourceTreeOperationsQemu(LinuxSourceTreeOperations): > > > '-no-reboot', > > > '-nographic', > > > '-serial', self._serial] + self._extra_qemu_params > > > + accelerators = { > > > + line.strip() > > > + for line in subprocess.check_output([qemu_binary, "-accel", "help"], text=True).splitlines() > > > + if line and line.islower() > > > + } > > > + if 'kvm' in accelerators: > > > + try: > > > + with open('/dev/kvm', 'rb+'): > > > + qemu_command.extend(['-accel', 'kvm']) > > > + except OSError as e: > > > + print(e) > > > + elif 'hvf' in accelerators: > > > + try: > > > + for line in subprocess.check_output(['sysctl', 'kern.hv_support'], text=True).splitlines(): > > > + if not line: > > > + continue > > > + key, value = line.split(':') > > > + if key == 'kern.hv_support' and bool(value): > > > + qemu_command.extend(['-accel', 'hvf']) > > > + break > > > + except subprocess.CalledProcessError as e: > > > + print(e) > > > + > > > > QEMU supports falling back if one accelerator is not available, if you > > specify multiple like -accel kvm:tcg. Couldn't you rely on that rather > > than re-implementing the availability checks here? > > Have you ever used that? Here's what I get when I try: > > tamird@Tamirs-MacBook-Pro linux % tools/testing/kunit/kunit.py run > --arch arm64 --make_options LLVM=1 --raw_output=all > [10:45:03] Configuring KUnit Kernel ... > [10:45:03] Building KUnit Kernel ... > Populating config with: > $ make ARCH=arm64 O=.kunit olddefconfig LLVM=1 > Building with: > $ make all compile_commands.json ARCH=arm64 O=.kunit --jobs=12 LLVM=1 > [10:45:07] Starting KUnit Kernel (1/1)... > Running tests with: > $ qemu-system-aarch64 -nodefaults -m 1024 -kernel > .kunit/arch/arm64/boot/Image.gz -append 'kunit.enable=1 > console=ttyAMA0 kunit_shutdown=reboot' -no-reboot -nographic -serial > stdio -accel kvm:tcg -machine virt -cpu max > qemu-system-aarch64: -accel kvm:tcg: invalid accelerator kvm:tcg > > The same thing happens with hvf:kvm:tcg or just hvf:tcg. That syntax is for -machine accel=hvf:kvm:tcg. But you can also specify -accel multiple times. > I also can't find this in the documentation. -accel name[,prop=value[,...]] This is used to enable an accelerator. [..] If there is more than one accelerator specified, the next one is used if the previous one fails to initialize. -machine [type=]name[,prop=value[,...]] Supported machine properties are: accel=accels1[:accels2[:...]] [..] If there is more than one accelerator specified, the next one is used if the previous one fails to initialize. Thomas