Merge tag 'x86-core-2023-10-29-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 core updates from Thomas Gleixner:

 - Limit the hardcoded topology quirk for Hygon CPUs to those which have
   a model ID less than 4.

   The newer models have the topology CPUID leaf 0xB correctly
   implemented and are not affected.

 - Make SMT control more robust against enumeration failures

   SMT control was added to allow controlling SMT at boottime or
   runtime. The primary purpose was to provide a simple mechanism to
   disable SMT in the light of speculation attack vectors.

   It turned out that the code is sensible to enumeration failures and
   worked only by chance for XEN/PV. XEN/PV has no real APIC enumeration
   which means the primary thread mask is not set up correctly. By
   chance a XEN/PV boot ends up with smp_num_siblings == 2, which makes
   the hotplug control stay at its default value "enabled". So the mask
   is never evaluated.

   The ongoing rework of the topology evaluation caused XEN/PV to end up
   with smp_num_siblings == 1, which sets the SMT control to "not
   supported" and the empty primary thread mask causes the hotplug core
   to deny the bringup of the APS.

   Make the decision logic more robust and take 'not supported' and 'not
   implemented' into account for the decision whether a CPU should be
   booted or not.

 - Fake primary thread mask for XEN/PV

   Pretend that all XEN/PV vCPUs are primary threads, which makes the
   usage of the primary thread mask valid on XEN/PV. That is consistent
   with because all of the topology information on XEN/PV is fake or
   even non-existent.

 - Encapsulate topology information in cpuinfo_x86

   Move the randomly scattered topology data into a separate data
   structure for readability and as a preparatory step for the topology
   evaluation overhaul.

 - Consolidate APIC ID data type to u32

   It's fixed width hardware data and not randomly u16, int, unsigned
   long or whatever developers decided to use.

 - Cure the abuse of cpuinfo for persisting logical IDs.

   Per CPU cpuinfo is used to persist the logical package and die IDs.
   That's really not the right place simply because cpuinfo is subject
   to be reinitialized when a CPU goes through an offline/online cycle.

   Use separate per CPU data for the persisting to enable the further
   topology management rework. It will be removed once the new topology
   management is in place.

 - Provide a debug interface for inspecting topology information

   Useful in general and extremly helpful for validating the topology
   management rework in terms of correctness or "bug" compatibility.

* tag 'x86-core-2023-10-29-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  x86/apic, x86/hyperv: Use u32 in hv_snp_boot_ap() too
  x86/cpu: Provide debug interface
  x86/cpu/topology: Cure the abuse of cpuinfo for persisting logical ids
  x86/apic: Use u32 for wakeup_secondary_cpu[_64]()
  x86/apic: Use u32 for [gs]et_apic_id()
  x86/apic: Use u32 for phys_pkg_id()
  x86/apic: Use u32 for cpu_present_to_apicid()
  x86/apic: Use u32 for check_apicid_used()
  x86/apic: Use u32 for APIC IDs in global data
  x86/apic: Use BAD_APICID consistently
  x86/cpu: Move cpu_l[l2]c_id into topology info
  x86/cpu: Move logical package and die IDs into topology info
  x86/cpu: Remove pointless evaluation of x86_coreid_bits
  x86/cpu: Move cu_id into topology info
  x86/cpu: Move cpu_core_id into topology info
  hwmon: (fam15h_power) Use topology_core_id()
  scsi: lpfc: Use topology_core_id()
  x86/cpu: Move cpu_die_id into topology info
  x86/cpu: Move phys_proc_id into topology info
  x86/cpu: Encapsulate topology information in cpuinfo_x86
  ...

1 files changed, 5 insertions, 7 deletions

diff --git a/Documentation/arch/x86/topology.rst b/Documentation/arch/x86/topology.rst
index 7f58010ea86afb..08ebf9edbfc1ed 100644
--- a/Documentation/arch/x86/topology.rst
+++ b/Documentation/arch/x86/topology.rst
@@ -55,19 +55,19 @@ Package-related topology information in the kernel:
 
     The number of dies in a package. This information is retrieved via CPUID.
 
-  - cpuinfo_x86.cpu_die_id:
+  - cpuinfo_x86.topo.die_id:
 
     The physical ID of the die. This information is retrieved via CPUID.
 
-  - cpuinfo_x86.phys_proc_id:
+  - cpuinfo_x86.topo.pkg_id:
 
     The physical ID of the package. This information is retrieved via CPUID
     and deduced from the APIC IDs of the cores in the package.
 
     Modern systems use this value for the socket. There may be multiple
-    packages within a socket. This value may differ from cpu_die_id.
+    packages within a socket. This value may differ from topo.die_id.
 
-  - cpuinfo_x86.logical_proc_id:
+  - cpuinfo_x86.topo.logical_pkg_id:
 
     The logical ID of the package. As we do not trust BIOSes to enumerate the
     packages in a consistent way, we introduced the concept of logical package
@@ -79,9 +79,7 @@ Package-related topology information in the kernel:
     The maximum possible number of packages in the system. Helpful for per
     package facilities to preallocate per package information.
 
-  - cpu_llc_id:
-
-    A per-CPU variable containing:
+  - cpuinfo_x86.topo.llc_id:
 
       - On Intel, the first APIC ID of the list of CPUs sharing the Last Level
         Cache