On Thu, Nov 02, 2023 at 07:44:45PM -0300, Daniel Henrique Barboza wrote: > There's no gain in allowing the 'max' CPU to support profiles, since it > already contains everything that QEMU can support. And we'll open the > door for 'unorthodox' stuff like users disabling profiles of the 'max' > CPU.
I don't see a lot of value in this patch, but maybe I'm just too cruel to users that don't know what they're doing. I even see a negative value to this patch because I can conceive of writing a script where I generally want to use rv64i with my explicit list of profiles/extensions, but then I may want to temporarily "boost" my CPU to 'max' for some reason. If I write my script like CPU=rv64i EXTENSIONS=profile=on,extension=on qemu -cpu $CPU,$EXTENSIONS ... then I can't just do CPU=max ./my-script to boost my CPU, since max will error out when it sees profiles being enabled (even though that should be no-op for it). Instead, I need to do CPU=max EXTENSIONS= ./my-script which isn't horrible, but a bit annoying. So, personally, I would drop this patch. Thanks, drew > > Signed-off-by: Daniel Henrique Barboza <dbarb...@ventanamicro.com> > --- > target/riscv/tcg/tcg-cpu.c | 16 +++++++++++----- > 1 file changed, 11 insertions(+), 5 deletions(-) > > diff --git a/target/riscv/tcg/tcg-cpu.c b/target/riscv/tcg/tcg-cpu.c > index 553fb337e7..9a964a426e 100644 > --- a/target/riscv/tcg/tcg-cpu.c > +++ b/target/riscv/tcg/tcg-cpu.c > @@ -825,6 +825,11 @@ static bool riscv_cpu_is_vendor(Object *cpu_obj) > return object_dynamic_cast(cpu_obj, TYPE_RISCV_VENDOR_CPU) != NULL; > } > > +static bool riscv_cpu_has_max_extensions(Object *cpu_obj) > +{ > + return object_dynamic_cast(cpu_obj, TYPE_RISCV_CPU_MAX) != NULL; > +} > + > /* > * We'll get here via the following path: > * > @@ -1003,6 +1008,12 @@ static void cpu_set_profile(Object *obj, Visitor *v, > const char *name, > return; > } > > + if (riscv_cpu_has_max_extensions(obj)) { > + error_setg(errp, "Profile %s is not available for the 'max' CPU", > + profile->name); > + return; > + } > + > if (cpu->env.misa_mxl != MXL_RV64) { > error_setg(errp, "Profile %s only available for 64 bit CPUs", > profile->name); > @@ -1251,11 +1262,6 @@ static void riscv_init_max_cpu_extensions(Object *obj) > } > } > > -static bool riscv_cpu_has_max_extensions(Object *cpu_obj) > -{ > - return object_dynamic_cast(cpu_obj, TYPE_RISCV_CPU_MAX) != NULL; > -} > - > static void tcg_cpu_instance_init(CPUState *cs) > { > RISCVCPU *cpu = RISCV_CPU(cs); > -- > 2.41.0 >