| Message ID | 20240203040515.23947-9-ricardo.neri-calderon@linux.intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | thermal: intel: hfi: Prework for the virtualization of HFI | expand |
On Fri, Feb 02, 2024 at 08:05:14PM -0800, Ricardo Neri wrote: > +static __always_inline void setup_hreset(struct cpuinfo_x86 *c) > +{ > + if (!cpu_feature_enabled(X86_FEATURE_HRESET)) > + return; > + > + /* > + * Use on all CPUs the hardware history features that the boot > + * CPU supports. > + */ > + if (c == &boot_cpu_data) > + hardware_history_features = cpuid_ebx(0x20); That's not what this does - that sets hardware_history_features on the BSP. Why isn't this whole thing called in bsp_init_intel()?
On Sat, Feb 03, 2024 at 10:38:57AM +0100, Borislav Petkov wrote: > On Fri, Feb 02, 2024 at 08:05:14PM -0800, Ricardo Neri wrote: > > +static __always_inline void setup_hreset(struct cpuinfo_x86 *c) > > +{ > > + if (!cpu_feature_enabled(X86_FEATURE_HRESET)) > > + return; > > + > > + /* > > + * Use on all CPUs the hardware history features that the boot > > + * CPU supports. > > + */ > > + if (c == &boot_cpu_data) > > + hardware_history_features = cpuid_ebx(0x20); > > That's not what this does - that sets hardware_history_features on the > BSP. I meant to say that we will use the features that the BSP supports and use them to configure all other CPUs. I will reword the comment to make this clear. > > Why isn't this whole thing called in bsp_init_intel()? The register MSR_IA32_HW_HRESET_ENABLE needs to be configured on each CPU. I can set hardware_history_features from bsp_init_intel() but I still need to call setup_hreset() on every CPU.
On Sat, Feb 03, 2024 at 07:55:52PM -0800, Ricardo Neri wrote: > I can set hardware_history_features from bsp_init_intel() but I still > need to call setup_hreset() on every CPU. init_intel() runs on every CPU.
On Sun, Feb 04, 2024 at 11:49:04AM +0100, Borislav Petkov wrote: > On Sat, Feb 03, 2024 at 07:55:52PM -0800, Ricardo Neri wrote: > > I can set hardware_history_features from bsp_init_intel() but I still > > need to call setup_hreset() on every CPU. > > init_intel() runs on every CPU. I see. Yes, this looks like the place to setup HRESET. Thank you for the pointer!
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 0b97bcde70c6..bce8719b47c9 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -381,6 +381,26 @@ static __always_inline void setup_umip(struct cpuinfo_x86 *c) cr4_clear_bits(X86_CR4_UMIP); } +static u32 hardware_history_features __ro_after_init; + +static __always_inline void setup_hreset(struct cpuinfo_x86 *c) +{ + if (!cpu_feature_enabled(X86_FEATURE_HRESET)) + return; + + /* + * Use on all CPUs the hardware history features that the boot + * CPU supports. + */ + if (c == &boot_cpu_data) + hardware_history_features = cpuid_ebx(0x20); + + if (!hardware_history_features) + return; + + wrmsrl(MSR_IA32_HW_HRESET_ENABLE, hardware_history_features); +} + /* These bits should not change their value after CPU init is finished. */ static const unsigned long cr4_pinned_mask = X86_CR4_SMEP | X86_CR4_SMAP | X86_CR4_UMIP | @@ -1872,10 +1892,11 @@ static void identify_cpu(struct cpuinfo_x86 *c) /* Disable the PN if appropriate */ squash_the_stupid_serial_number(c); - /* Set up SMEP/SMAP/UMIP */ + /* Set up SMEP/SMAP/UMIP/HRESET */ setup_smep(c); setup_smap(c); setup_umip(c); + setup_hreset(c); /* Enable FSGSBASE instructions if available. */ if (cpu_has(c, X86_FEATURE_FSGSBASE)) {
Configure the MSR that controls the behavior of HRESET on each logical processor. Cc: Len Brown <len.brown@intel.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Cc: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com> Cc: Zhao Liu <zhao1.liu@linux.intel.com> Cc: Zhuocheng Ding <zhuocheng.ding@intel.com> Cc: x86@kernel.org Cc: linux-pm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> --- Patch cherry-picked from the IPC classes patchset --- --- arch/x86/kernel/cpu/common.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-)