diff options
| -rw-r--r-- | arch/x86/include/asm/apic.h | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/acpi/boot.c | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/apic/apic.c | 19 |
3 files changed, 23 insertions, 1 deletions
diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h index 9362a3aae927..ef40e4acd7c2 100644 --- a/arch/x86/include/asm/apic.h +++ b/arch/x86/include/asm/apic.h @@ -504,8 +504,10 @@ extern int default_check_phys_apicid_present(int phys_apicid); #ifdef CONFIG_SMP bool apic_id_is_primary_thread(unsigned int id); +bool apic_id_disabled(unsigned int id); #else static inline bool apic_id_is_primary_thread(unsigned int id) { return false; } +static inline bool apic_id_disabled(unsigned int id) { return false; } #endif extern void irq_enter(void); diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c index 3b20607d581b..db4c118a7e4d 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -181,7 +181,8 @@ static int acpi_register_lapic(int id, u32 acpiid, u8 enabled) } if (!enabled) { - ++disabled_cpus; + if (!apic_id_disabled(id)) + ++disabled_cpus; return -EINVAL; } diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index 8703caa9d6db..b86091add294 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -2204,6 +2204,16 @@ bool apic_id_is_primary_thread(unsigned int apicid) return !(apicid & mask); } +/** + * apic_id_disabled - Check whether APIC ID is disabled via SMT control + * @id: APIC ID to check + */ +bool apic_id_disabled(unsigned int id) +{ + return (cpu_smt_control == CPU_SMT_FORCE_DISABLED && + !apic_id_is_primary_thread(id)); +} + /* * Should use this API to allocate logical CPU IDs to keep nr_logical_cpuids * and cpuid_to_apicid[] synchronized. @@ -2299,6 +2309,15 @@ int generic_processor_info(int apicid, int version) return -EINVAL; } + /* + * If SMT is force disabled and the APIC ID belongs to + * a secondary thread, ignore it. + */ + if (apic_id_disabled(apicid)) { + pr_info_once("Ignoring secondary SMT threads\n"); + return -EINVAL; + } + if (apicid == boot_cpu_physical_apicid) { /* * x86_bios_cpu_apicid is required to have processors listed |