| Message ID | 3431308.1mSSVdqTRr@kreacher (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Delegated to: | Rafael Wysocki |
| Headers | show |
| Series | x86: intel_epb: Take CONFIG_PM into account | expand |
* Rafael J. Wysocki <rjw@rjwysocki.net> wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > Commit b9c273babce7 (PM / arch: x86: MSR_IA32_ENERGY_PERF_BIAS sysfs > interface) caused kernels built with CONFIG_PM unset to crash on > systems supporting the Performance and Energy Bias Hint (EPB), > because it attempts to add files to sysfs directories that don't > exist on those systems. > > Prevent that from happening by taking CONFIG_PM into account so > that the code depending on it is not compiled at all when it is > not set. > > Fixes: b9c273babce7 (PM / arch: x86: MSR_IA32_ENERGY_PERF_BIAS sysfs interface) > Reported-by: Ido Schimmel <idosch@mellanox.com> > Tested-by: Ido Schimmel <idosch@mellanox.com> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > --- > arch/x86/kernel/cpu/intel_epb.c | 22 +++++++++++++++++++++- > 1 file changed, 21 insertions(+), 1 deletion(-) Acked-by: Ingo Molnar <mingo@kernel.org> Thanks, Ingo
Index: linux-pm/arch/x86/kernel/cpu/intel_epb.c =================================================================== --- linux-pm.orig/arch/x86/kernel/cpu/intel_epb.c +++ linux-pm/arch/x86/kernel/cpu/intel_epb.c @@ -97,6 +97,7 @@ static void intel_epb_restore(void) wrmsrl(MSR_IA32_ENERGY_PERF_BIAS, (epb & ~EPB_MASK) | val); } +#ifdef CONFIG_PM static struct syscore_ops intel_epb_syscore_ops = { .suspend = intel_epb_save, .resume = intel_epb_restore, @@ -193,6 +194,25 @@ static int intel_epb_offline(unsigned in return 0; } +static inline void register_intel_ebp_syscore_ops(void) +{ + register_syscore_ops(&intel_epb_syscore_ops); +} +#else /* !CONFIG_PM */ +static int intel_epb_online(unsigned int cpu) +{ + intel_epb_restore(); + return 0; +} + +static int intel_epb_offline(unsigned int cpu) +{ + return intel_epb_save(); +} + +static inline void register_intel_ebp_syscore_ops(void) {} +#endif + static __init int intel_epb_init(void) { int ret; @@ -206,7 +226,7 @@ static __init int intel_epb_init(void) if (ret < 0) goto err_out_online; - register_syscore_ops(&intel_epb_syscore_ops); + register_intel_ebp_syscore_ops(); return 0; err_out_online: