Thomas Gleixner 2066f00e5b x86/topology: Implement topology_is_core_online() to address SMT regression ... Christian reported that commit a430c11f40 ("intel_idle: Rescan "dead" SMT siblings during initialization") broke the use case in which both 'nosmt' and 'maxcpus' are on the kernel command line because it onlines primary threads, which were offline due to the maxcpus limit. The initially proposed fix to skip primary threads in the loop is inconsistent. While it prevents the primary thread to be onlined, it then onlines the corresponding hyperthread(s), which does not really make sense. The CPU iterator in cpuhp_smt_enable() contains a check which excludes all threads of a core, when the primary thread is offline. The default implementation is a NOOP and therefore not effective on x86. Implement topology_is_core_online() on x86 to address this issue. This makes the behaviour consistent between x86 and PowerPC. Fixes: a430c11f40 ("intel_idle: Rescan "dead" SMT siblings during initialization") Fixes: f694481b1d ("ACPI: processor: Rescan "dead" SMT siblings during initialization") Closes: https://lore.kernel.org/linux-pm/724616a2-6374-4ba3-8ce3-ea9c45e2ae3b@arm.com/ Reported-by: Christian Loehle <christian.loehle@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org> Tested-by: Christian Loehle <christian.loehle@arm.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/12740505.O9o76ZdvQC@rafael.j.wysocki		2025-09-22 21:25:36 +02:00
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mce	x86/mce: Make sure CMCI banks are cleared during shutdown on Intel	2025-06-28 12:45:48 +02:00
microcode	x86/microcode/AMD: Handle the case of no BIOS microcode	2025-08-27 10:24:10 +02:00
mtrr	…
resctrl	x86,fs/resctrl: Remove inappropriate references to cacheinfo in the resctrl subsystem	2025-06-16 21:06:12 +02:00
sgx	mm: update architecture and driver code to use vm_flags_t	2025-07-09 22:42:14 -07:00
.gitignore	…
Makefile	…
acrn.c	…
amd.c	x86/CPU/AMD: Ignore invalid reset reason value	2025-08-18 16:36:59 +02:00
amd_cache_disable.c	…
aperfmperf.c	…
bugs.c	Mitigate VMSCAPE issue with indirect branch predictor flushes	2025-09-10 20:52:16 -07:00
bus_lock.c	…
cacheinfo.c	x86/cacheinfo: Rename CPUID(0x2) descriptors iterator parameter	2025-05-16 10:49:55 +02:00
centaur.c	…
common.c	x86/vmscape: Add old Intel CPUs to affected list	2025-08-29 15:28:52 -07:00
cpu.h	…
cpuid-deps.c	…
cpuid_0x2_table.c	…
cyrix.c	…
debugfs.c	…
feat_ctl.c	…
hygon.c	x86/cpu/hygon: Add missing resctrl_cpu_detect() in bsp_init helper	2025-08-18 12:09:26 +02:00
hypervisor.c	…
intel.c	x86/cpu/intel: Fix the constant_tsc model check for Pentium 4	2025-08-25 08:23:37 -07:00
intel_epb.c	…
match.c	…
mkcapflags.sh	…
mshyperv.c	…
perfctr-watchdog.c	…
powerflags.c	…
proc.c	…
rdrand.c	…
scattered.c	x86/sev: Evict cache lines during SNP memory validation	2025-08-06 19:17:22 +02:00
topology.c	x86/topology: Implement topology_is_core_online() to address SMT regression	2025-09-22 21:25:36 +02:00
topology.h	…
topology_amd.c	x86/cpu/topology: Always try cpu_parse_topology_ext() on AMD/Hygon	2025-09-08 11:37:49 +02:00
topology_common.c	…
topology_ext.c	…
transmeta.c	…
tsx.c	…
umc.c	…
umwait.c	…
vmware.c	…
vortex.c	…
zhaoxin.c	…