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Moreover, mentioning BIOS here > makes the messages even more confusing. > > Fix it by bailing out early when running in virtual machines (excluding > Xen Dom0). Conceptually this makes sense to me, but I would like some comments from others if this is the right way forward. Jason, Boris, comments please? > > Fixes: cb817ec6673b ("cpufreq: amd-pstate: show CPPC debug message if CPPC is not supported") > Signed-off-by: Rong Zhang > --- > drivers/cpufreq/amd-pstate.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c > index a74a4cf99d22..f2115f935318 100644 > --- a/drivers/cpufreq/amd-pstate.c > +++ b/drivers/cpufreq/amd-pstate.c > @@ -2228,6 +2228,9 @@ static int __init amd_pstate_init(void) > if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) > return -ENODEV; > > + if (cpu_feature_enabled(X86_FEATURE_HYPERVISOR) && !xen_initial_domain()) > + return -ENODEV; > + > /* show debug message only if CPPC is not supported */ > if (!amd_cppc_supported()) > return -EOPNOTSUPP; > > --- > base-commit: 58717b2a1365d06c8c64b72aa948541b53fe31eb > change-id: 1cc24037-amd-pstate-vm-d6ab4c959bd3 > > Thanks, > Rong >