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dependency #96

CPU topology series:
There are totally 5 series for this new cpu topology.
1st has been in 6.6, 2nd, 3rd, 4th, 5th series will be backported to 6.6. This PR is 4th patch series.

patch series 1: [patch V3 00/60] x86/apic: Decrapification and static calls
https://lore.kernel.org/all/20230801103042.936020332@linutronix.de/
Patches are merged in 6.6-rc1
Patch series 2: [patch V4 00/41] x86/cpu: Rework the topology evaluation
https://lore.kernel.org/all/20230814085006.593997112@linutronix.de/
Patch 1-22 merged in 6.7-rc1
Patch series 3: [patch V6 00/19] x86/cpu: Rework topology evaluation
https://lore.kernel.org/all/20240212153109.330805450@linutronix.de/
Patch series 4: [patch V3 00/22] x86/topology: More cleanups and preparatory work
https://lore.kernel.org/all/20240212154529.402604963@linutronix.de/
Patch series 5: [patch 00/30] x86/apic: Rework APIC registration
https://lore.kernel.org/all/20240213205415.307029033@linutronix.de/
Patches are merged in this merge window and should be included in 6.9-rc1.

Testing:
Intel platform
EMR/SRFSP/GNRSP/CWF/DMR simics testing - PASS

Testing Process:
git clone https://github.com/intel/lkvs
cd lkvs/BM

testcase-1:
#./runtests -c cpu_topology.sh -t numa_nodes_compare
[RESULT][cpu_topology.sh] [PASS] [0] [0.163s]
testcase-2:
./runtests -c cpu_topology.sh -t verify_thread_per_core
[RESULT][cpu_topology.sh] [PASS] [0] [0.158s]
testcase-3:
#./runtests -c cpu_topology.sh -t verify_cores_per_socket
[RESULT][cpu_topology.sh] [PASS] [0] [0.158s]
testcase-4:
#./runtests -c cpu_topology.sh -t verify_socket_num
[RESULT][cpu_topology.sh] [PASS] [0] [0.155s]
testcase-5:
#./runtests -c cpu_topology.sh -t verify_level_type
[RESULT][cpu_topology.sh] [PASS] [0] [0.158s]

package dependency: cpuid tools (used by test 1-5)

KAGA-KOKO and others added 30 commits December 15, 2025 22:12
commit 94f0b39 upstream.

Use the provided topology helper function instead of fiddling in cpu_data.

Intel-SIG: commit 94f0b39 hwmon: (fam15h_power) Use topology_core_id().
x86/cpu: Rework the topology evaluation - part1

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085112.506988471@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit e952563 upstream.

Rename it to core_id and stick it to the other ID fields.

No functional change.

Intel-SIG: commit e952563 x86/cpu: Move cpu_core_id into topology info.
x86/cpu: Rework the topology evaluation - part1

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085112.566519388@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit e3c0c5d upstream.

No functional change.

Intel-SIG: commit e3c0c5d x86/cpu: Move cu_id into topology info.
x86/cpu: Rework the topology evaluation - part1

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085112.628405546@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 594957d upstream.

cpuinfo_x86::x86_coreid_bits is only used by the AMD numa topology code. No
point in evaluating it on non AMD systems.

No functional change.

Intel-SIG: commit 594957d x86/cpu: Remove pointless evaluation of x86_coreid_bits.
x86/cpu: Rework the topology evaluation - part1

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085112.687588373@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 22dc963 upstream.

Yet another topology related data pair. Rename logical_proc_id to
logical_pkg_id so it fits the common naming conventions.

No functional change.

Intel-SIG: commit 22dc963 x86/cpu: Move logical package and die IDs into topology info.
x86/cpu: Rework the topology evaluation - part1

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085112.745139505@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 6e29032 upstream.

The topology IDs which identify the LLC and L2 domains clearly belong to
the per CPU topology information.

Move them into cpuinfo_x86::cpuinfo_topo and get rid of the extra per CPU
data and the related exports.

This also paves the way to do proper topology evaluation during early boot
because it removes the only per CPU dependency for that.

No functional change.

Intel-SIG: commit 6e29032 x86/cpu: Move cpu_l[l2]c_id into topology info.
x86/cpu: Rework the topology evaluation - part1

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085112.803864641@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 9ff4275 upstream.

APIC ID checks compare with BAD_APICID all over the place, but some
initializers and some code which fiddles with global data structure use
-1[U] instead. That simply cannot work at all.

Fix it up and use BAD_APICID consistently all over the place.

Intel-SIG: commit 9ff4275 x86/apic: Use BAD_APICID consistently.
x86/cpu: Rework the topology evaluation - part1

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085112.862835121@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 4705243 upstream.

APIC IDs are used with random data types u16, u32, int, unsigned int,
unsigned long.

Make it all consistently use u32 because that reflects the hardware
register width and fixup the most obvious usage sites of that.

The APIC callbacks will be addressed separately.

Intel-SIG: commit 4705243 x86/apic: Use u32 for APIC IDs in global data.
x86/cpu: Rework the topology evaluation - part1

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085112.922905727@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 5d376b8 upstream.

APIC IDs are used with random data types u16, u32, int, unsigned int,
unsigned long.

Make it all consistently use u32 because that reflects the hardware
register width and move the default implementation to local.h as there are
no users outside the apic directory.

Intel-SIG: commit 5d376b8 x86/apic: Use u32 for check_apicid_used().
x86/cpu: Rework the topology evaluation - part1

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085112.981956102@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 8aa2a41 upstream.

APIC IDs are used with random data types u16, u32, int, unsigned int,
unsigned long.

Make it all consistently use u32 because that reflects the hardware
register width and fixup a few related usage sites for consistency sake.

Intel-SIG: commit 8aa2a41 x86/apic: Use u32 for cpu_present_to_apicid().
x86/cpu: Rework the topology evaluation - part1

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085113.054064391@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 01ccf9b upstream.

APIC IDs are used with random data types u16, u32, int, unsigned int,
unsigned long.

Make it all consistently use u32 because that reflects the hardware
register width even if that callback going to be removed soonish.

Intel-SIG: commit 01ccf9b x86/apic: Use u32 for phys_pkg_id().
x86/cpu: Rework the topology evaluation - part1

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085113.113097126@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 59f7928 upstream.

APIC IDs are used with random data types u16, u32, int, unsigned int,
unsigned long.

Make it all consistently use u32 because that reflects the hardware
register width.

Intel-SIG: commit 59f7928 x86/apic: Use u32 for [gs]et_apic_id().
x86/cpu: Rework the topology evaluation - part1

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085113.172569282@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 92fe9bb upstream.

The data type for APIC IDs was standardized to 'u32' in the
following recent commit:

   db4a408 ("x86/apic: Use u32 for wakeup_secondary_cpu[_64]()")

Which changed the function arguments type signature of the
apic->wakeup_secondary_cpu() APIC driver function.

Propagate this to hv_snp_boot_ap() as well, which also addresses a
'assignment from incompatible pointer type' build warning that triggers
under the -Werror=incompatible-pointer-types GCC warning.

Fixes: db4a408 ("x86/apic: Use u32 for wakeup_secondary_cpu[_64]()")
Intel-SIG: commit 92fe9bb x86/apic, x86/hyperv: Use u32 in hv_snp_boot_ap() too.
x86/cpu: Rework the topology evaluation - part1

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230814085113.233274223@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit db4a408 upstream.

APIC IDs are used with random data types u16, u32, int, unsigned int,
unsigned long.

Make it all consistently use u32 because that reflects the hardware
register width.

Intel-SIG: commit db4a408 x86/apic: Use u32 for wakeup_secondary_cpu[_64]().
x86/cpu: Rework the topology evaluation - part1

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085113.233274223@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 90781f0 upstream.

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.

This works by chance today, but that's far from correct and neither obvious
nor documented.

Add a per cpu datastructure which persists those logical IDs, which allows
to cleanup the CPUID evaluation code.

This is a temporary workaround until the larger topology management is in
place, which makes all of this logical management mechanics obsolete.

Intel-SIG: commit 90781f0 x86/cpu/topology: Cure the abuse of cpuinfo for persisting logical ids.
x86/cpu: Rework the topology evaluation - part1

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085113.292947071@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 48525fd upstream.

Provide debug files which dump the topology related information of
cpuinfo_x86. This is useful to validate the upcoming conversion of the
topology evaluation for correctness or bug compatibility.

Intel-SIG: commit 48525fd x86/cpu: Provide debug interface.
x86/cpu: Rework the topology evaluation - part1

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085113.353191313@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 43d86e3 upstream.

Provide a few helper functions to read CPUID leafs or individual registers
into a data structure without requiring unions.

Intel-SIG: commit 43d86e3 x86/cpu: Provide cpuid_read() et al..
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/878r3mg570.ffs@tglx
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 97c7d5723537de08e076892e07d6089ae9777965 upstream.

<asm/cpuid.h> uses static_assert() at multiple locations but it does not
include the CPP macro's definition at linux/build_bug.h.

Include the needed header to make <asm/cpuid.h> self-sufficient.

This gets triggered when cpuid.h is included in new C files, which is to
be done in further commits.

Fixes: 43d86e3 ("x86/cpu: Provide cpuid_read() et al.")
Intel-SIG: commit 97c7d5723537 x86/cpuid: Include <linux/build_bug.h> in <asm/cpuid.h>.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20250304085152.51092-5-darwi@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit ebdb203 upstream.

Topology evaluation is a complete disaster and impenetrable mess. It's
scattered all over the place with some vendor implementations doing early
evaluation and some not. The most horrific part is the permanent
overwriting of smt_max_siblings and __max_die_per_package, instead of
establishing them once on the boot CPU and validating the result on the
APs.

The goals are:

  - One topology evaluation entry point

  - Proper sharing of pointlessly duplicated code

  - Proper structuring of the evaluation logic and preferences.

  - Evaluating important system wide information only once on the boot CPU

  - Making the 0xb/0x1f leaf parsing less convoluted and actually fixing
    the short comings of leaf 0x1f evaluation.

Start to consolidate the topology evaluation code by providing the entry
points for the early boot CPU evaluation and for the final parsing on the
boot CPU and the APs.

Move the trivial pieces into that new code:

   - The initialization of cpuinfo_x86::topo

   - The evaluation of CPUID leaf 1, which presets topo::initial_apicid

   - topo_apicid is set to topo::initial_apicid when invoked from early
     boot. When invoked for the final evaluation on the boot CPU it reads
     the actual APIC ID, which makes apic_get_initial_apicid() obsolete
     once everything is converted over.

Provide a temporary helper function topo_converted() which shields off the
not yet converted CPU vendors from invoking code which would break them.
This shielding covers all vendor CPUs which support SMP, but not the
historical pure UP ones as they only need the topology info init and
eventually the initial APIC initialization.

Provide two new members in cpuinfo_x86::topo to store the maximum number of
SMT siblings and the number of dies per package and add them to the debugfs
readout. These two members will be used to populate this information on the
boot CPU and to validate the APs against it.

Intel-SIG: commit ebdb203 x86/cpu: Provide cpu_init/parse_topology().
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240212153624.581436579@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit bda74aa upstream.

The legacy topology detection via CPUID leaf 4, which provides the number
of cores in the package and CPUID leaf 1 which provides the number of
logical CPUs in case that FEATURE_HT is enabled and the CMP_LEGACY feature
is not set, is shared for Intel, Centaur and Zhaoxin CPUs.

Lift the code from common.c without the early detection hack and provide it
as common fallback mechanism.

Will be utilized in later changes.

Intel-SIG: commit bda74aa x86/cpu: Add legacy topology parser.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153624.644448852@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 598e719 upstream.

Centaur and Zhaoxin CPUs use only the legacy SMP detection. Remove the
invocations from their 32bit path and exclude them from the 64-bit call
path.

No functional change intended.

Intel-SIG: commit 598e719 x86/cpu: Use common topology code for Centaur and Zhaoxin.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153624.706794189@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 92853a7 upstream.

In preparation of a complete replacement for the topology leaf 0xb/0x1f
evaluation, move __max_die_per_package into the common code.

Will be removed once everything is converted over.

Intel-SIG: commit 92853a7 x86/cpu: Move __max_die_per_package to common.c.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153624.768188958@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 3d41009 upstream.

detect_extended_topology() along with it's early() variant is a classic
example for duct tape engineering:

  - It evaluates an array of subleafs with a boatload of local variables
    for the relevant topology levels instead of using an array to save the
    enumerated information and propagate it to the right level

  - It has no boundary checks for subleafs

  - It prevents updating the die_id with a crude workaround instead of
    checking for leaf 0xb which does not provide die information.

  - It's broken vs. the number of dies evaluation as it uses:

      num_processors[DIE_LEVEL] / num_processors[CORE_LEVEL]

    which "works" only correctly if there is none of the intermediate
    topology levels (MODULE/TILE) enumerated.

There is zero value in trying to "fix" that code as the only proper fix is
to rewrite it from scratch.

Implement a sane parser with proper code documentation, which will be used
for the consolidated topology evaluation in the next step.

Intel-SIG: commit 3d41009 x86/cpu: Provide a sane leaf 0xb/0x1f parser.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153624.830571770@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 22d6366 upstream.

Intel CPUs use either topology leaf 0xb/0x1f evaluation or the legacy
SMP/HT evaluation based on CPUID leaf 0x1/0x4.

Move it over to the consolidated topology code and remove the random
topology hacks which are sprinkled into the Intel and the common code.

No functional change intended.

Intel-SIG: commit 22d6366 x86/cpu: Use common topology code for Intel.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153624.893644349@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 0c2f6d0 upstream.

Intel CPUs have a MSR bit to limit CPUID enumeration to leaf two. If
this bit is set by the BIOS then CPUID evaluation including topology
enumeration does not work correctly as the evaluation code does not try
to analyze any leaf greater than two.

This went unnoticed before because the original topology code just
repeated evaluation several times and managed to overwrite the initial
limited information with the correct one later. The new evaluation code
does it once and therefore ends up with the limited and wrong
information.

Cure this by unlocking CPUID right before evaluating anything which
depends on the maximum CPUID leaf being greater than two instead of
rereading stuff after unlock.

Fixes: 22d6366 ("x86/cpu: Use common topology code for Intel")
Reported-by: Peter Schneider <pschneider1968@googlemail.com>
Intel-SIG: commit 0c2f6d0 x86/topology/intel: Unlock CPUID before evaluating anything.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Peter Schneider <pschneider1968@googlemail.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/fd3f73dc-a86f-4bcf-9c60-43556a21eb42@googlemail.com
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit f7fb3b2 upstream.

AMD/HYGON uses various methods for topology evaluation:

  - Leaf 0x80000008 and 0x8000001e based with an optional leaf 0xb,
    which is the preferred variant for modern CPUs.

    Leaf 0xb will be superseded by leaf 0x80000026 soon, which is just
    another variant of the Intel 0x1f leaf for whatever reasons.

  - Subleaf 0x80000008 and NODEID_MSR base

  - Legacy fallback

That code is following the principle of random bits and pieces all over the
place which results in multiple evaluations and impenetrable code flows in
the same way as the Intel parsing did.

Provide a sane implementation by clearly separating the three variants and
bringing them in the proper preference order in one place.

This provides the parsing for both AMD and HYGON because there is no point
in having a separate HYGON parser which only differs by 3 lines of
code. Any further divergence between AMD and HYGON can be handled in
different functions, while still sharing the existing parsers.

Intel-SIG: commit f7fb3b2 x86/cpu: Provide an AMD/HYGON specific topology parser.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153625.020038641@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 1b3108f upstream.

CPUID 0x80000008 ECX.cpu_nthreads describes the number of threads in the
package. The parser uses this value to initialize the SMT domain level.

That's wrong because cpu_nthreads does not describe the number of threads
per physical core. So this needs to set the CORE domain level and let the
later parsers set the SMT shift if available.

Preset the SMT domain level with the assumption of one thread per core,
which is correct ifrt here are no other CPUID leafs to parse, and propagate
cpu_nthreads and the core level APIC bitwidth into the CORE domain.

Fixes: f7fb3b2 ("x86/cpu: Provide an AMD/HYGON specific topology parser")
Reported-by: "kernelci.org bot" <bot@kernelci.org>
Reported-by: Laura Nao <laura.nao@collabora.com>
Intel-SIG: commit 1b3108f x86/cpu/amd: Make the CPUID 0x80000008 parser correct.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Laura Nao <laura.nao@collabora.com>
Link: https://lore.kernel.org/r/20240410194311.535206450@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit c064b53 upstream.

A system with NODEID_MSR was reported to crash during early boot without
any output.

The reason is that the union which is used for accessing the bitfields in
the MSR is written wrongly and the resulting executable code accesses the
wrong part of the MSR data.

As a consequence a later division by that value results in 0 and that
result is used for another division as divisor, which obviously does not
work well.

The magic world of C, unions and bitfields:

    union {
    	  u64   bita : 3,
	        bitb : 3;
	  u64   all;
    } x;

    x.all = foo();

    a = x.bita;
    b = x.bitb;

results in the effective executable code of:

   a = b = x.bita;

because bita and bitb are treated as union members and therefore both end
up at bit offset 0.

Wrapping the bitfield into an anonymous struct:

    union {
    	  struct {
    	     u64  bita : 3,
	          bitb : 3;
          };
	  u64	  all;
    } x;

works like expected.

Rework the NODEID_MSR union in exactly that way to cure the problem.

Fixes: f7fb3b2 ("x86/cpu: Provide an AMD/HYGON specific topology parser")
Reported-by: "kernelci.org bot" <bot@kernelci.org>
Reported-by: Laura Nao <laura.nao@collabora.com>
Intel-SIG: commit c064b53 x86/cpu/amd: Make the NODEID_MSR union actually work.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Laura Nao <laura.nao@collabora.com>
Link: https://lore.kernel.org/r/20240410194311.596282919@linutronix.de
Closes: https://lore.kernel.org/all/20240322175210.124416-1-laura.nao@collabora.com/
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 7211274 upstream.

The topology rework missed that early_init_amd() tries to re-enable the
Topology Extensions when the BIOS disabled them.

The new parser is invoked before early_init_amd() so the re-enable attempt
happens too late.

Move it into the AMD specific topology parser code where it belongs.

Fixes: f7fb3b2 ("x86/cpu: Provide an AMD/HYGON specific topology parser")
Intel-SIG: commit 7211274 x86/cpu/amd: Move TOPOEXT enablement into the topology parser.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/878r1j260l.ffs@tglx
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 5754ace upstream.

The original topology evaluation code initialized cpu_data::topo::llc_id
with the die ID initialy and then eventually overwrite it with information
gathered from a CPUID leaf.

The conversion analysis failed to spot that particular detail and omitted
this initial assignment under the assumption that each topology evaluation
path will set it up. That assumption is mostly correct, but turns out to be
wrong in case that the CPUID leaf 0x80000006 does not provide a LLC ID.

In that case, LLC ID is invalid and as a consequence the setup of the
scheduling domain CPU masks is incorrect which subsequently causes the
scheduler core to complain about it during CPU hotplug:

  BUG: arch topology borken
       the CLS domain not a subset of the MC domain

Cure it by reusing legacy_set_llc() and assigning the die ID if the LLC ID
is invalid after all possible parsers have been tried.

Fixes: f7fb3b2 ("x86/cpu: Provide an AMD/HYGON specific topology parser")
Reported-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Intel-SIG: commit 5754ace x86/topology/amd: Ensure that LLC ID is initialized.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Link: https://lore.kernel.org/r/PUZPR04MB63168AC442C12627E827368581292@PUZPR04MB6316.apcprd04.prod.outlook.com
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
KAGA-KOKO and others added 12 commits December 15, 2025 22:12
…y 0x17 and greater

commit 34bf6ba upstream.

The new AMD/HYGON topology parser evaluates the SMT information in CPUID leaf
0x8000001e unconditionally while the original code restricted it to CPUs with
family 0x17 and greater.

This breaks family 0x15 CPUs which advertise that leaf and have a non-zero
value in the SMT section. The machine boots, but the scheduler complains loudly
about the mismatch of the core IDs:

  WARNING: CPU: 1 PID: 0 at kernel/sched/core.c:6482 sched_cpu_starting+0x183/0x250
  WARNING: CPU: 0 PID: 1 at kernel/sched/topology.c:2408 build_sched_domains+0x76b/0x12b0

Add the condition back to cure it.

  [ bp: Make it actually build because grandpa is not concerned with
    trivial stuff. :-P ]

Fixes: f7fb3b2 ("x86/cpu: Provide an AMD/HYGON specific topology parser")
Closes: https://gitlab.archlinux.org/archlinux/packaging/packages/linux/-/issues/56
Reported-by: Tim Teichmann <teichmanntim@outlook.de>
Reported-by: Christian Heusel <christian@heusel.eu>
Intel-SIG: commit 34bf6ba x86/topology/amd: Evaluate SMT in CPUID leaf 0x8000001e only on family 0x17 and greater.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Tim Teichmann <teichmanntim@outlook.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/7skhx6mwe4hxiul64v6azhlxnokheorksqsdbp7qw6g2jduf6c@7b5pvomauugk
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit ace278e upstream.

When switching AMD over to the new topology parser then the match functions
need to look for AMD systems with the extended topology feature at the new
topo.amd_node_id member which is then holding the node id information.

Intel-SIG: commit ace278e x86/smpboot: Teach it about topo.amd_node_id.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153625.082979150@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit c749ce3 upstream.

Switch it over to the new topology evaluation mechanism and remove the
random bits and pieces which are sprinkled all over the place.

No functional change intended.

Intel-SIG: commit c749ce3 x86/cpu: Use common topology code for AMD.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153625.145745053@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 3279081 upstream.

Switch it over to use the consolidated topology evaluation and remove the
temporary safe guards which are not longer needed.

No functional change intended.

Intel-SIG: commit 3279081 x86/cpu: Use common topology code for HYGON.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153625.207750409@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit d805a69 upstream.

cpuinfo::topo::x86_coreid_bits is about to be phased out. Use the core
domain size from the topology information.

Add a comment why the early MPTABLE parsing is required and decrapify the
loop which sets the APIC ID to node map.

Intel-SIG: commit d805a69 x86/mm/numa: Use core domain size on AMD.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153625.270320718@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 03fa6be upstream.

Now that everything is converted switch it over and remove the intermediate
operation.

Intel-SIG: commit 03fa6be x86/cpu: Make topology_amd_node_id() use the actual node info.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153625.334185785@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 6cf7039 upstream.

No more users. Stick it into the ugly code museum.

Intel-SIG: commit 6cf7039 x86/cpu: Remove topology.c.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153625.395230346@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit fab75e7 upstream.

No more users.

Intel-SIG: commit fab75e7 x86/cpu: Remove x86_coreid_bits.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153625.455839743@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit 035fc90 upstream.

Now that the core code does not use this monstrosity anymore, it's time to
put it to rest.

The only real purpose was to read the APIC ID on UV and VSMP systems for
the actual evaluation. That's what the core code does now.

For doing the actual shift operation there is truly no APIC callback
required.

Intel-SIG: commit 035fc90 x86/apic: Remove unused phys_pkg_id() callback.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153625.516536121@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit d5474e4 upstream.

The new topology CPUID parser installs already fake topology for XEN/PV,
which ends up with cpuinfo::max_cores = 1.

Intel-SIG: commit d5474e4 x86/xen/smp_pv: Remove cpudata fiddling.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153625.576579177@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
commit bcccdf8 upstream.

The package shift has been already evaluated by the early CPU init.

Put the mindless copy right next to the original leaf 0xb parser.

Intel-SIG: commit bcccdf8 x86/apic/uv: Remove the private leaf 0xb parser.
x86/cpu: Rework the topology evaluation - part2

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lore.kernel.org/r/20240212153625.637385562@linutronix.de
[ Quanxian Wang: amend commit log ]
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
Signed-off-by: Quanxian Wang <quanxian.wang@intel.com>
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will use intel repo to submit PRs

PvsNarasimha pushed a commit to PvsNarasimha/kernel that referenced this pull request Jan 23, 2026
[ Upstream commit ffb34a60ce86656ba12d46e91f1ccc71dd221251 ]

Reorder the initialization sequence in `usbhs_probe()` to enable runtime
PM before accessing registers, preventing potential crashes due to
uninitialized clocks.

Currently, in the probe path, registers are accessed before enabling the
clocks, leading to a synchronous external abort on the RZ/V2H SoC.
The problematic call flow is as follows:

    usbhs_probe()
        usbhs_sys_clock_ctrl()
            usbhs_bset()
                usbhs_write()
                    iowrite16()  <-- Register access before enabling clocks

Since `iowrite16()` is performed without ensuring the required clocks are
enabled, this can lead to access errors. To fix this, enable PM runtime
early in the probe function and ensure clocks are acquired before register
access, preventing crashes like the following on RZ/V2H:

[13.272640] Internal error: synchronous external abort: 0000000096000010 [openvelinux#1] PREEMPT SMP
[13.280814] Modules linked in: cec renesas_usbhs(+) drm_kms_helper fuse drm backlight ipv6
[13.289088] CPU: 1 UID: 0 PID: 195 Comm: (udev-worker) Not tainted 6.14.0-rc7+ openvelinux#98
[13.296640] Hardware name: Renesas RZ/V2H EVK Board based on r9a09g057h44 (DT)
[13.303834] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[13.310770] pc : usbhs_bset+0x14/0x4c [renesas_usbhs]
[13.315831] lr : usbhs_probe+0x2e4/0x5ac [renesas_usbhs]
[13.321138] sp : ffff8000827e3850
[13.324438] x29: ffff8000827e3860 x28: 0000000000000000 x27: ffff8000827e3ca0
[13.331554] x26: ffff8000827e3ba0 x25: ffff800081729668 x24: 0000000000000025
[13.338670] x23: ffff0000c0f08000 x22: 0000000000000000 x21: ffff0000c0f08010
[13.345783] x20: 0000000000000000 x19: ffff0000c3b52080 x18: 00000000ffffffff
[13.352895] x17: 0000000000000000 x16: 0000000000000000 x15: ffff8000827e36ce
[13.360009] x14: 00000000000003d7 x13: 00000000000003d7 x12: 0000000000000000
[13.367122] x11: 0000000000000000 x10: 0000000000000aa0 x9 : ffff8000827e3750
[13.374235] x8 : ffff0000c1850b00 x7 : 0000000003826060 x6 : 000000000000001c
[13.381347] x5 : 000000030d5fcc00 x4 : ffff8000825c0000 x3 : 0000000000000000
[13.388459] x2 : 0000000000000400 x1 : 0000000000000000 x0 : ffff0000c3b52080
[13.395574] Call trace:
[13.398013]  usbhs_bset+0x14/0x4c [renesas_usbhs] (P)
[13.403076]  platform_probe+0x68/0xdc
[13.406738]  really_probe+0xbc/0x2c0
[13.410306]  __driver_probe_device+0x78/0x120
[13.414653]  driver_probe_device+0x3c/0x154
[13.418825]  __driver_attach+0x90/0x1a0
[13.422647]  bus_for_each_dev+0x7c/0xe0
[13.426470]  driver_attach+0x24/0x30
[13.430032]  bus_add_driver+0xe4/0x208
[13.433766]  driver_register+0x68/0x130
[13.437587]  __platform_driver_register+0x24/0x30
[13.442273]  renesas_usbhs_driver_init+0x20/0x1000 [renesas_usbhs]
[13.448450]  do_one_initcall+0x60/0x1d4
[13.452276]  do_init_module+0x54/0x1f8
[13.456014]  load_module+0x1754/0x1c98
[13.459750]  init_module_from_file+0x88/0xcc
[13.464004]  __arm64_sys_finit_module+0x1c4/0x328
[13.468689]  invoke_syscall+0x48/0x104
[13.472426]  el0_svc_common.constprop.0+0xc0/0xe0
[13.477113]  do_el0_svc+0x1c/0x28
[13.480415]  el0_svc+0x30/0xcc
[13.483460]  el0t_64_sync_handler+0x10c/0x138
[13.487800]  el0t_64_sync+0x198/0x19c
[13.491453] Code: 2a0103e1 12003c42 12003c63 8b010084 (79400084)
[13.497522] ---[ end trace 0000000000000000 ]---

Fixes: f1407d5 ("usb: renesas_usbhs: Add Renesas USBHS common code")
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20250407105002.107181-4-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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