From af2e518c4300a581900c10e6a62e28b2fe1aa8d9 Mon Sep 17 00:00:00 2001 From: Chengwen Feng Date: Thu, 19 Mar 2026 14:57:29 +0800 Subject: [PATCH 1/7] arm64/acpi: Add acpi_get_cpu_uid() and switch arm_cspmu to use it Add arch-specific acpi_get_cpu_uid() for arm64, and update dependent code: - Declare acpi_get_cpu_uid() in arch/arm64/include/asm/acpi.h - Implement acpi_get_cpu_uid() with input parameter validation - Replace get_acpi_id_for_cpu() with acpi_get_cpu_uid() in drivers/perf/arm_cspmu/arm_cspmu.c - Reimplement get_cpu_for_acpi_id() based on acpi_get_cpu_uid() (to align with new interface) and move its implementation next to acpi_get_cpu_uid() This is the first step towards unifying ACPI CPU UID retrieval interface across architectures, while adding input validation for robustness. Cc: stable@vger.kernel.org Signed-off-by: Chengwen Feng Reviewed-by: Jonathan Cameron Signed-off-by: Linux RISC-V bot --- arch/arm64/include/asm/acpi.h | 14 ++------------ arch/arm64/kernel/acpi.c | 30 ++++++++++++++++++++++++++++++ drivers/perf/arm_cspmu/arm_cspmu.c | 6 ++++-- 3 files changed, 36 insertions(+), 14 deletions(-) diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h index c07a58b96329d8..2219a3301e722b 100644 --- a/arch/arm64/include/asm/acpi.h +++ b/arch/arm64/include/asm/acpi.h @@ -118,18 +118,8 @@ static inline u32 get_acpi_id_for_cpu(unsigned int cpu) { return acpi_cpu_get_madt_gicc(cpu)->uid; } - -static inline int get_cpu_for_acpi_id(u32 uid) -{ - int cpu; - - for (cpu = 0; cpu < nr_cpu_ids; cpu++) - if (acpi_cpu_get_madt_gicc(cpu) && - uid == get_acpi_id_for_cpu(cpu)) - return cpu; - - return -EINVAL; -} +int acpi_get_cpu_uid(unsigned int cpu, u32 *uid); +int get_cpu_for_acpi_id(u32 uid); static inline void arch_fix_phys_package_id(int num, u32 slot) { } void __init acpi_init_cpus(void); diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c index af90128cfed56d..24b9d934be547c 100644 --- a/arch/arm64/kernel/acpi.c +++ b/arch/arm64/kernel/acpi.c @@ -458,3 +458,33 @@ int acpi_unmap_cpu(int cpu) } EXPORT_SYMBOL(acpi_unmap_cpu); #endif /* CONFIG_ACPI_HOTPLUG_CPU */ + +int acpi_get_cpu_uid(unsigned int cpu, u32 *uid) +{ + struct acpi_madt_generic_interrupt *gicc; + + if (cpu >= nr_cpu_ids) + return -EINVAL; + + gicc = acpi_cpu_get_madt_gicc(cpu); + if (!gicc) + return -ENODEV; + + *uid = gicc->uid; + return 0; +} +EXPORT_SYMBOL_GPL(acpi_get_cpu_uid); + +int get_cpu_for_acpi_id(u32 uid) +{ + u32 cpu_uid; + int ret; + + for (int cpu = 0; cpu < nr_cpu_ids; cpu++) { + ret = acpi_get_cpu_uid(cpu, &cpu_uid); + if (ret == 0 && uid == cpu_uid) + return cpu; + } + + return -EINVAL; +} diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c b/drivers/perf/arm_cspmu/arm_cspmu.c index 34430b68f60254..ed72c3d1f79678 100644 --- a/drivers/perf/arm_cspmu/arm_cspmu.c +++ b/drivers/perf/arm_cspmu/arm_cspmu.c @@ -1107,15 +1107,17 @@ static int arm_cspmu_acpi_get_cpus(struct arm_cspmu *cspmu) { struct acpi_apmt_node *apmt_node; int affinity_flag; + u32 cpu_uid; int cpu; + int ret; apmt_node = arm_cspmu_apmt_node(cspmu->dev); affinity_flag = apmt_node->flags & ACPI_APMT_FLAGS_AFFINITY; if (affinity_flag == ACPI_APMT_FLAGS_AFFINITY_PROC) { for_each_possible_cpu(cpu) { - if (apmt_node->proc_affinity == - get_acpi_id_for_cpu(cpu)) { + ret = acpi_get_cpu_uid(cpu, &cpu_uid); + if (ret == 0 && apmt_node->proc_affinity == cpu_uid) { cpumask_set_cpu(cpu, &cspmu->associated_cpus); break; } From 2c7d622d489d77aa45170f4dce64a26479307147 Mon Sep 17 00:00:00 2001 From: Chengwen Feng Date: Thu, 19 Mar 2026 14:57:30 +0800 Subject: [PATCH 2/7] loongarch/acpi: Add acpi_get_cpu_uid() declaration and implementation Add arch-specific acpi_get_cpu_uid() for loongarch: - Declare acpi_get_cpu_uid() in arch/loongarch/include/asm/acpi.h - Implement acpi_get_cpu_uid() with input parameter validation Align loongarch with the new unified ACPI CPU UID retrieval interface, preparing for replacement of the legacy get_acpi_id_for_cpu() (to be removed in follow-up patches). Cc: stable@vger.kernel.org Signed-off-by: Chengwen Feng Reviewed-by: Jonathan Cameron Signed-off-by: Linux RISC-V bot --- arch/loongarch/include/asm/acpi.h | 1 + arch/loongarch/kernel/acpi.c | 9 +++++++++ 2 files changed, 10 insertions(+) diff --git a/arch/loongarch/include/asm/acpi.h b/arch/loongarch/include/asm/acpi.h index 7376840fa9f78a..8bb101b4557e17 100644 --- a/arch/loongarch/include/asm/acpi.h +++ b/arch/loongarch/include/asm/acpi.h @@ -44,6 +44,7 @@ static inline u32 get_acpi_id_for_cpu(unsigned int cpu) { return acpi_core_pic[cpu_logical_map(cpu)].processor_id; } +int acpi_get_cpu_uid(unsigned int cpu, u32 *uid); #endif /* !CONFIG_ACPI */ diff --git a/arch/loongarch/kernel/acpi.c b/arch/loongarch/kernel/acpi.c index 1367ca759468f9..058f0dbe8e8f97 100644 --- a/arch/loongarch/kernel/acpi.c +++ b/arch/loongarch/kernel/acpi.c @@ -385,3 +385,12 @@ int acpi_unmap_cpu(int cpu) EXPORT_SYMBOL(acpi_unmap_cpu); #endif /* CONFIG_ACPI_HOTPLUG_CPU */ + +int acpi_get_cpu_uid(unsigned int cpu, u32 *uid) +{ + if (cpu >= nr_cpu_ids) + return -EINVAL; + *uid = acpi_core_pic[cpu_logical_map(cpu)].processor_id; + return 0; +} +EXPORT_SYMBOL_GPL(acpi_get_cpu_uid); From 04f0fb59b585a9add86b251a88655b84e16e30f9 Mon Sep 17 00:00:00 2001 From: Chengwen Feng Date: Thu, 19 Mar 2026 14:57:31 +0800 Subject: [PATCH 3/7] riscv/acpi: Add acpi_get_cpu_uid() implementation and update users Add arch-specific acpi_get_cpu_uid() for riscv: - Declare acpi_get_cpu_uid() in arch/riscv/include/asm/acpi.h - Implement acpi_get_cpu_uid() with input parameter validation - Switch rhct.c and arch/riscv/kernel/acpi_numa.c to use acpi_get_cpu_uid() instead of get_acpi_id_for_cpu() This aligns riscv with the unified ACPI CPU UID interface, improving input validation and consistency across ACPI-enabled platforms. Cc: stable@vger.kernel.org Signed-off-by: Chengwen Feng Reviewed-by: Jonathan Cameron Signed-off-by: Linux RISC-V bot --- arch/riscv/include/asm/acpi.h | 1 + arch/riscv/kernel/acpi.c | 16 ++++++++++++++++ arch/riscv/kernel/acpi_numa.c | 9 ++++++--- drivers/acpi/riscv/rhct.c | 7 ++++++- 4 files changed, 29 insertions(+), 4 deletions(-) diff --git a/arch/riscv/include/asm/acpi.h b/arch/riscv/include/asm/acpi.h index 6e13695120bc21..f3520cc85af327 100644 --- a/arch/riscv/include/asm/acpi.h +++ b/arch/riscv/include/asm/acpi.h @@ -65,6 +65,7 @@ static inline u32 get_acpi_id_for_cpu(int cpu) { return acpi_cpu_get_madt_rintc(cpu)->uid; } +int acpi_get_cpu_uid(unsigned int cpu, u32 *uid); int acpi_get_riscv_isa(struct acpi_table_header *table, unsigned int cpu, const char **isa); diff --git a/arch/riscv/kernel/acpi.c b/arch/riscv/kernel/acpi.c index 26c018ebce03c5..12d22fab892bc6 100644 --- a/arch/riscv/kernel/acpi.c +++ b/arch/riscv/kernel/acpi.c @@ -337,3 +337,19 @@ int raw_pci_write(unsigned int domain, unsigned int bus, } #endif /* CONFIG_PCI */ + +int acpi_get_cpu_uid(unsigned int cpu, u32 *uid) +{ + struct acpi_madt_rintc *rintc; + + if (cpu >= nr_cpu_ids) + return -EINVAL; + + rintc = acpi_cpu_get_madt_rintc(cpu); + if (!rintc) + return -ENODEV; + + *uid = rintc->uid; + return 0; +} +EXPORT_SYMBOL_GPL(acpi_get_cpu_uid); diff --git a/arch/riscv/kernel/acpi_numa.c b/arch/riscv/kernel/acpi_numa.c index 130769e3a99c3b..6a2d4289f806e4 100644 --- a/arch/riscv/kernel/acpi_numa.c +++ b/arch/riscv/kernel/acpi_numa.c @@ -37,11 +37,14 @@ static int __init acpi_numa_get_nid(unsigned int cpu) static inline int get_cpu_for_acpi_id(u32 uid) { - int cpu; + u32 cpu_uid; + int ret; - for (cpu = 0; cpu < nr_cpu_ids; cpu++) - if (uid == get_acpi_id_for_cpu(cpu)) + for (int cpu = 0; cpu < nr_cpu_ids; cpu++) { + ret = acpi_get_cpu_uid(cpu, &cpu_uid); + if (ret == 0 && uid == cpu_uid) return cpu; + } return -EINVAL; } diff --git a/drivers/acpi/riscv/rhct.c b/drivers/acpi/riscv/rhct.c index caa2c16e16974a..8f3f38c64a88aa 100644 --- a/drivers/acpi/riscv/rhct.c +++ b/drivers/acpi/riscv/rhct.c @@ -44,10 +44,15 @@ int acpi_get_riscv_isa(struct acpi_table_header *table, unsigned int cpu, const struct acpi_rhct_isa_string *isa_node; struct acpi_table_rhct *rhct; u32 *hart_info_node_offset; - u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); + u32 acpi_cpu_id; + int ret; BUG_ON(acpi_disabled); + ret = acpi_get_cpu_uid(cpu, &acpi_cpu_id); + if (ret != 0) + return ret; + if (!table) { rhct = acpi_get_rhct(); if (!rhct) From 06b946385994c8e29d5082f24270ac9544b9a6f7 Mon Sep 17 00:00:00 2001 From: Chengwen Feng Date: Thu, 19 Mar 2026 14:57:32 +0800 Subject: [PATCH 4/7] x86/acpi: Add acpi_get_cpu_uid() implementation and update Xen users Add arch-specific acpi_get_cpu_uid() for x86: - Declare acpi_get_cpu_uid() in arch/x86/include/asm/acpi.h - Implement acpi_get_cpu_uid() with input parameter validation - Replace cpu_acpi_id() with acpi_get_cpu_uid() in Xen-related code - Remove the now-unused cpu_acpi_id() function Extend the unified ACPI CPU UID interface to x86, ensuring consistent error handling and input validation across all ACPI-enabled architectures. Cc: stable@vger.kernel.org Signed-off-by: Chengwen Feng Reviewed-by: Jonathan Cameron Reviewed-by: Juergen Gross Signed-off-by: Linux RISC-V bot --- arch/x86/include/asm/acpi.h | 2 ++ arch/x86/include/asm/cpu.h | 1 - arch/x86/include/asm/smp.h | 1 - arch/x86/kernel/acpi/boot.c | 20 ++++++++++++++++++++ arch/x86/xen/enlighten_hvm.c | 5 +++-- 5 files changed, 25 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/acpi.h b/arch/x86/include/asm/acpi.h index a03aa6f999d158..92b5c27c4fea81 100644 --- a/arch/x86/include/asm/acpi.h +++ b/arch/x86/include/asm/acpi.h @@ -157,6 +157,8 @@ static inline bool acpi_has_cpu_in_madt(void) return !!acpi_lapic; } +int acpi_get_cpu_uid(unsigned int cpu, u32 *uid); + #define ACPI_HAVE_ARCH_SET_ROOT_POINTER static __always_inline void acpi_arch_set_root_pointer(u64 addr) { diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h index ad235dda1ded0f..57a0786dfd75da 100644 --- a/arch/x86/include/asm/cpu.h +++ b/arch/x86/include/asm/cpu.h @@ -11,7 +11,6 @@ #ifndef CONFIG_SMP #define cpu_physical_id(cpu) boot_cpu_physical_apicid -#define cpu_acpi_id(cpu) 0 #endif /* CONFIG_SMP */ #ifdef CONFIG_HOTPLUG_CPU diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h index 84951572ab8170..05d1d479b4cf3d 100644 --- a/arch/x86/include/asm/smp.h +++ b/arch/x86/include/asm/smp.h @@ -130,7 +130,6 @@ __visible void smp_call_function_interrupt(struct pt_regs *regs); __visible void smp_call_function_single_interrupt(struct pt_regs *r); #define cpu_physical_id(cpu) per_cpu(x86_cpu_to_apicid, cpu) -#define cpu_acpi_id(cpu) per_cpu(x86_cpu_to_acpiid, cpu) /* * This function is needed by all SMP systems. It must _always_ be valid diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c index a3f2fb1fea1bc9..ceba24f65ae3a8 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -1848,3 +1848,23 @@ void __iomem * (*acpi_os_ioremap)(acpi_physical_address phys, acpi_size size) = x86_acpi_os_ioremap; EXPORT_SYMBOL_GPL(acpi_os_ioremap); #endif + +int acpi_get_cpu_uid(unsigned int cpu, u32 *uid) +{ + u32 acpi_id; + + if (cpu >= nr_cpu_ids) + return -EINVAL; + +#ifdef CONFIG_SMP + acpi_id = per_cpu(x86_cpu_to_acpiid, cpu); + if (acpi_id == CPU_ACPIID_INVALID) + return -ENODEV; +#else + acpi_id = 0; +#endif + + *uid = acpi_id; + return 0; +} +EXPORT_SYMBOL_GPL(acpi_get_cpu_uid); diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c index fe57ff85d004ba..2f9fa27e5a3c23 100644 --- a/arch/x86/xen/enlighten_hvm.c +++ b/arch/x86/xen/enlighten_hvm.c @@ -151,6 +151,7 @@ static void xen_hvm_crash_shutdown(struct pt_regs *regs) static int xen_cpu_up_prepare_hvm(unsigned int cpu) { + u32 cpu_uid; int rc = 0; /* @@ -161,8 +162,8 @@ static int xen_cpu_up_prepare_hvm(unsigned int cpu) */ xen_uninit_lock_cpu(cpu); - if (cpu_acpi_id(cpu) != CPU_ACPIID_INVALID) - per_cpu(xen_vcpu_id, cpu) = cpu_acpi_id(cpu); + if (acpi_get_cpu_uid(cpu, &cpu_uid) == 0) + per_cpu(xen_vcpu_id, cpu) = cpu_uid; else per_cpu(xen_vcpu_id, cpu) = cpu; xen_vcpu_setup(cpu); From eda493e837d71e74cf147511498196454e72e59d Mon Sep 17 00:00:00 2001 From: Chengwen Feng Date: Thu, 19 Mar 2026 14:57:33 +0800 Subject: [PATCH 5/7] ACPI: Centralize acpi_get_cpu_uid() declaration in include/linux/acpi.h - Add acpi_get_cpu_uid() prototype to include/linux/acpi.h (global scope) - Remove arch-specific acpi_get_cpu_uid() declarations from arm64/loongarch/riscv/x86 asm/acpi.h This centralizes the interface declaration for consistency, avoiding duplicate prototypes across architectures and simplifying future maintenance. Cc: stable@vger.kernel.org Signed-off-by: Chengwen Feng Reviewed-by: Jonathan Cameron Signed-off-by: Linux RISC-V bot --- arch/arm64/include/asm/acpi.h | 1 - arch/loongarch/include/asm/acpi.h | 1 - arch/riscv/include/asm/acpi.h | 1 - arch/x86/include/asm/acpi.h | 2 -- include/linux/acpi.h | 11 +++++++++++ 5 files changed, 11 insertions(+), 5 deletions(-) diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h index 2219a3301e722b..bdb0ecf95b5c65 100644 --- a/arch/arm64/include/asm/acpi.h +++ b/arch/arm64/include/asm/acpi.h @@ -118,7 +118,6 @@ static inline u32 get_acpi_id_for_cpu(unsigned int cpu) { return acpi_cpu_get_madt_gicc(cpu)->uid; } -int acpi_get_cpu_uid(unsigned int cpu, u32 *uid); int get_cpu_for_acpi_id(u32 uid); static inline void arch_fix_phys_package_id(int num, u32 slot) { } diff --git a/arch/loongarch/include/asm/acpi.h b/arch/loongarch/include/asm/acpi.h index 8bb101b4557e17..7376840fa9f78a 100644 --- a/arch/loongarch/include/asm/acpi.h +++ b/arch/loongarch/include/asm/acpi.h @@ -44,7 +44,6 @@ static inline u32 get_acpi_id_for_cpu(unsigned int cpu) { return acpi_core_pic[cpu_logical_map(cpu)].processor_id; } -int acpi_get_cpu_uid(unsigned int cpu, u32 *uid); #endif /* !CONFIG_ACPI */ diff --git a/arch/riscv/include/asm/acpi.h b/arch/riscv/include/asm/acpi.h index f3520cc85af327..6e13695120bc21 100644 --- a/arch/riscv/include/asm/acpi.h +++ b/arch/riscv/include/asm/acpi.h @@ -65,7 +65,6 @@ static inline u32 get_acpi_id_for_cpu(int cpu) { return acpi_cpu_get_madt_rintc(cpu)->uid; } -int acpi_get_cpu_uid(unsigned int cpu, u32 *uid); int acpi_get_riscv_isa(struct acpi_table_header *table, unsigned int cpu, const char **isa); diff --git a/arch/x86/include/asm/acpi.h b/arch/x86/include/asm/acpi.h index 92b5c27c4fea81..a03aa6f999d158 100644 --- a/arch/x86/include/asm/acpi.h +++ b/arch/x86/include/asm/acpi.h @@ -157,8 +157,6 @@ static inline bool acpi_has_cpu_in_madt(void) return !!acpi_lapic; } -int acpi_get_cpu_uid(unsigned int cpu, u32 *uid); - #define ACPI_HAVE_ARCH_SET_ROOT_POINTER static __always_inline void acpi_arch_set_root_pointer(u64 addr) { diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 3a412dcebc296d..da43177da4028f 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -324,6 +324,17 @@ int acpi_unmap_cpu(int cpu); acpi_handle acpi_get_processor_handle(int cpu); +/** + * acpi_get_cpu_uid() - Get ACPI Processor UID of from MADT table + * @cpu: Logical CPU number (0-based) + * @uid: Pointer to store ACPI Processor UID + * + * Return: 0 on success (ACPI Processor ID stored in *uid); + * -EINVAL if CPU number is invalid or out of range; + * -ENODEV if ACPI Processor UID for the CPU is not found. + */ +int acpi_get_cpu_uid(unsigned int cpu, u32 *uid); + #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr); #endif From 7ae0dca8fcaa4f3a90170279ab61fd42cbee2616 Mon Sep 17 00:00:00 2001 From: Chengwen Feng Date: Thu, 19 Mar 2026 14:57:34 +0800 Subject: [PATCH 6/7] ACPI: PPTT: Use acpi_get_cpu_uid() and remove get_acpi_id_for_cpu() - Convert acpi/pptt.c to use acpi_get_cpu_uid() instead of get_acpi_id_for_cpu() - Remove unused get_acpi_id_for_cpu() implementations from arm64/loongarch/riscv This completes the migration to the unified ACPI CPU UID interface for PPTT code, and cleans up legacy unused functions to reduce technical debt. Cc: stable@vger.kernel.org Signed-off-by: Chengwen Feng Reviewed-by: Jonathan Cameron Signed-off-by: Linux RISC-V bot --- arch/arm64/include/asm/acpi.h | 4 --- arch/loongarch/include/asm/acpi.h | 5 ---- arch/riscv/include/asm/acpi.h | 4 --- drivers/acpi/pptt.c | 50 +++++++++++++++++++++++-------- 4 files changed, 37 insertions(+), 26 deletions(-) diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h index bdb0ecf95b5c65..8a54ca6ba60282 100644 --- a/arch/arm64/include/asm/acpi.h +++ b/arch/arm64/include/asm/acpi.h @@ -114,10 +114,6 @@ static inline bool acpi_has_cpu_in_madt(void) } struct acpi_madt_generic_interrupt *acpi_cpu_get_madt_gicc(int cpu); -static inline u32 get_acpi_id_for_cpu(unsigned int cpu) -{ - return acpi_cpu_get_madt_gicc(cpu)->uid; -} int get_cpu_for_acpi_id(u32 uid); static inline void arch_fix_phys_package_id(int num, u32 slot) { } diff --git a/arch/loongarch/include/asm/acpi.h b/arch/loongarch/include/asm/acpi.h index 7376840fa9f78a..eda9d4d0a493c1 100644 --- a/arch/loongarch/include/asm/acpi.h +++ b/arch/loongarch/include/asm/acpi.h @@ -40,11 +40,6 @@ extern struct acpi_madt_core_pic acpi_core_pic[MAX_CORE_PIC]; extern int __init parse_acpi_topology(void); -static inline u32 get_acpi_id_for_cpu(unsigned int cpu) -{ - return acpi_core_pic[cpu_logical_map(cpu)].processor_id; -} - #endif /* !CONFIG_ACPI */ #define ACPI_TABLE_UPGRADE_MAX_PHYS ARCH_LOW_ADDRESS_LIMIT diff --git a/arch/riscv/include/asm/acpi.h b/arch/riscv/include/asm/acpi.h index 6e13695120bc21..26ab37c171bcf6 100644 --- a/arch/riscv/include/asm/acpi.h +++ b/arch/riscv/include/asm/acpi.h @@ -61,10 +61,6 @@ static inline void arch_fix_phys_package_id(int num, u32 slot) { } void acpi_init_rintc_map(void); struct acpi_madt_rintc *acpi_cpu_get_madt_rintc(int cpu); -static inline u32 get_acpi_id_for_cpu(int cpu) -{ - return acpi_cpu_get_madt_rintc(cpu)->uid; -} int acpi_get_riscv_isa(struct acpi_table_header *table, unsigned int cpu, const char **isa); diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c index de5f8c018333d7..7bd5bc1f225a41 100644 --- a/drivers/acpi/pptt.c +++ b/drivers/acpi/pptt.c @@ -459,11 +459,14 @@ static void cache_setup_acpi_cpu(struct acpi_table_header *table, { struct acpi_pptt_cache *found_cache; struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); - u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); + u32 acpi_cpu_id; struct cacheinfo *this_leaf; unsigned int index = 0; struct acpi_pptt_processor *cpu_node = NULL; + if (acpi_get_cpu_uid(cpu, &acpi_cpu_id) != 0) + return; + while (index < get_cpu_cacheinfo(cpu)->num_leaves) { this_leaf = this_cpu_ci->info_list + index; found_cache = acpi_find_cache_node(table, acpi_cpu_id, @@ -546,7 +549,10 @@ static int topology_get_acpi_cpu_tag(struct acpi_table_header *table, unsigned int cpu, int level, int flag) { struct acpi_pptt_processor *cpu_node; - u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); + u32 acpi_cpu_id; + + if (acpi_get_cpu_uid(cpu, &acpi_cpu_id) != 0) + return -ENOENT; cpu_node = acpi_find_processor_node(table, acpi_cpu_id); if (cpu_node) { @@ -614,18 +620,22 @@ static int find_acpi_cpu_topology_tag(unsigned int cpu, int level, int flag) * * Check the node representing a CPU for a given flag. * - * Return: -ENOENT if the PPTT doesn't exist, the CPU cannot be found or - * the table revision isn't new enough. + * Return: -ENOENT if can't get CPU's ACPI Processor UID, the PPTT doesn't + * exist, the CPU cannot be found or the table revision isn't new + * enough. * 1, any passed flag set * 0, flag unset */ static int check_acpi_cpu_flag(unsigned int cpu, int rev, u32 flag) { struct acpi_table_header *table; - u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); + u32 acpi_cpu_id; struct acpi_pptt_processor *cpu_node = NULL; int ret = -ENOENT; + if (acpi_get_cpu_uid(cpu, &acpi_cpu_id) != 0) + return -ENOENT; + table = acpi_get_pptt(); if (!table) return -ENOENT; @@ -651,7 +661,8 @@ static int check_acpi_cpu_flag(unsigned int cpu, int rev, u32 flag) * in the PPTT. Errors caused by lack of a PPTT table, or otherwise, return 0 * indicating we didn't find any cache levels. * - * Return: -ENOENT if no PPTT table or no PPTT processor struct found. + * Return: -ENOENT if no PPTT table, can't get CPU's ACPI Process UID or no PPTT + * processor struct found. * 0 on success. */ int acpi_get_cache_info(unsigned int cpu, unsigned int *levels, @@ -671,7 +682,9 @@ int acpi_get_cache_info(unsigned int cpu, unsigned int *levels, pr_debug("Cache Setup: find cache levels for CPU=%d\n", cpu); - acpi_cpu_id = get_acpi_id_for_cpu(cpu); + if (acpi_get_cpu_uid(cpu, &acpi_cpu_id)) + return -ENOENT; + cpu_node = acpi_find_processor_node(table, acpi_cpu_id); if (!cpu_node) return -ENOENT; @@ -780,8 +793,9 @@ int find_acpi_cpu_topology_package(unsigned int cpu) * It may not exist in single CPU systems. In simple multi-CPU systems, * it may be equal to the package topology level. * - * Return: -ENOENT if the PPTT doesn't exist, the CPU cannot be found - * or there is no toplogy level above the CPU.. + * Return: -ENOENT if the PPTT doesn't exist, can't get CPU's ACPI + * Processor UID, the CPU cannot be found or there is no toplogy level + * above the CPU. * Otherwise returns a value which represents the package for this CPU. */ @@ -797,7 +811,9 @@ int find_acpi_cpu_topology_cluster(unsigned int cpu) if (!table) return -ENOENT; - acpi_cpu_id = get_acpi_id_for_cpu(cpu); + if (acpi_get_cpu_uid(cpu, &acpi_cpu_id) != 0) + return -ENOENT; + cpu_node = acpi_find_processor_node(table, acpi_cpu_id); if (!cpu_node || !cpu_node->parent) return -ENOENT; @@ -872,7 +888,9 @@ static void acpi_pptt_get_child_cpus(struct acpi_table_header *table_hdr, cpumask_clear(cpus); for_each_possible_cpu(cpu) { - acpi_id = get_acpi_id_for_cpu(cpu); + if (acpi_get_cpu_uid(cpu, &acpi_id) != 0) + continue; + cpu_node = acpi_find_processor_node(table_hdr, acpi_id); while (cpu_node) { @@ -966,10 +984,13 @@ int find_acpi_cache_level_from_id(u32 cache_id) for_each_possible_cpu(cpu) { bool empty; int level = 1; - u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); + u32 acpi_cpu_id; struct acpi_pptt_cache *cache; struct acpi_pptt_processor *cpu_node; + if (acpi_get_cpu_uid(cpu, &acpi_cpu_id) != 0) + continue; + cpu_node = acpi_find_processor_node(table, acpi_cpu_id); if (!cpu_node) continue; @@ -1030,10 +1051,13 @@ int acpi_pptt_get_cpumask_from_cache_id(u32 cache_id, cpumask_t *cpus) for_each_possible_cpu(cpu) { bool empty; int level = 1; - u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); + u32 acpi_cpu_id; struct acpi_pptt_cache *cache; struct acpi_pptt_processor *cpu_node; + if (acpi_get_cpu_uid(cpu, &acpi_cpu_id) != 0) + continue; + cpu_node = acpi_find_processor_node(table, acpi_cpu_id); if (!cpu_node) continue; From 82a435f616b9f44903247568475bb4cdddbbf799 Mon Sep 17 00:00:00 2001 From: Chengwen Feng Date: Thu, 19 Mar 2026 14:57:35 +0800 Subject: [PATCH 7/7] PCI/TPH: Fix get cpu steer-tag fail on ARM64 platform pcie_tph_get_cpu_st() is broken on ARM64: 1. pcie_tph_get_cpu_st() passes cpu_uid to the PCI ACPI DSM method. cpu_uid should be the ACPI Processor UID [1]. 2. In BNXT, pcie_tph_get_cpu_st() is passed a cpu_uid obtained via cpumask_first(irq->cpu_mask) - the logical CPU ID of a CPU core, generated and managed by kernel (e.g., [0,255] for a system with 256 logical CPU cores). 3. On ARM64 platforms, ACPI assigns Processor UID to cores listed in the MADT table, and this UID may not match the kernel's logical CPU ID. When this occurs, the mismatch results in the wrong CPU steer-tag. 4. On AMD x86 the logical CPU ID is identical to the ACPI Processor UID so the mismatch is not seen. Resolution: 1. Use acpi_get_cpu_uid() in pcie_tph_get_cpu_st() to translate from logical CPU ID to ACPI Processor UID needed for the DSM call. 2. Rename pcie_tpu_get_cpu_st() parameter from cpu_uid to cpu to reflect that it is a logical CPU_ID. [1] According to ECN_TPH-ST_Revision_20200924 (https://members.pcisig.com/wg/PCI-SIG/document/15470), the input is defined as: "If the target is a processor, then this field represents the ACPI Processor UID of the processor as specified in the MADT. If the target is a processor container, then this field represents the ACPI Processor UID of the processor container as specified in the PPTT." Fixes: d2e8a34876ce ("PCI/TPH: Add Steering Tag support") Cc: stable@vger.kernel.org Signed-off-by: Chengwen Feng Reviewed-by: Jonathan Cameron Signed-off-by: Linux RISC-V bot --- Documentation/PCI/tph.rst | 4 ++-- drivers/pci/tph.c | 16 +++++++++++----- include/linux/pci-tph.h | 4 ++-- 3 files changed, 15 insertions(+), 9 deletions(-) diff --git a/Documentation/PCI/tph.rst b/Documentation/PCI/tph.rst index e8993be64fd64d..b6cf22b9bd90a5 100644 --- a/Documentation/PCI/tph.rst +++ b/Documentation/PCI/tph.rst @@ -79,10 +79,10 @@ To retrieve a Steering Tag for a target memory associated with a specific CPU, use the following function:: int pcie_tph_get_cpu_st(struct pci_dev *pdev, enum tph_mem_type type, - unsigned int cpu_uid, u16 *tag); + unsigned int cpu, u16 *tag); The `type` argument is used to specify the memory type, either volatile -or persistent, of the target memory. The `cpu_uid` argument specifies the +or persistent, of the target memory. The `cpu` argument specifies the CPU where the memory is associated to. After the ST value is retrieved, the device driver can use the following diff --git a/drivers/pci/tph.c b/drivers/pci/tph.c index ca4f97be75389d..b67c9ad14bdaad 100644 --- a/drivers/pci/tph.c +++ b/drivers/pci/tph.c @@ -236,21 +236,27 @@ static int write_tag_to_st_table(struct pci_dev *pdev, int index, u16 tag) * with a specific CPU * @pdev: PCI device * @mem_type: target memory type (volatile or persistent RAM) - * @cpu_uid: associated CPU id + * @cpu: associated CPU id * @tag: Steering Tag to be returned * * Return the Steering Tag for a target memory that is associated with a - * specific CPU as indicated by cpu_uid. + * specific CPU as indicated by cpu. * * Return: 0 if success, otherwise negative value (-errno) */ int pcie_tph_get_cpu_st(struct pci_dev *pdev, enum tph_mem_type mem_type, - unsigned int cpu_uid, u16 *tag) + unsigned int cpu, u16 *tag) { #ifdef CONFIG_ACPI struct pci_dev *rp; acpi_handle rp_acpi_handle; union st_info info; + u32 cpu_uid; + int ret; + + ret = acpi_get_cpu_uid(cpu, &cpu_uid); + if (ret != 0) + return ret; rp = pcie_find_root_port(pdev); if (!rp || !rp->bus || !rp->bus->bridge) @@ -265,9 +271,9 @@ int pcie_tph_get_cpu_st(struct pci_dev *pdev, enum tph_mem_type mem_type, *tag = tph_extract_tag(mem_type, pdev->tph_req_type, &info); - pci_dbg(pdev, "get steering tag: mem_type=%s, cpu_uid=%d, tag=%#04x\n", + pci_dbg(pdev, "get steering tag: mem_type=%s, cpu=%d, tag=%#04x\n", (mem_type == TPH_MEM_TYPE_VM) ? "volatile" : "persistent", - cpu_uid, *tag); + cpu, *tag); return 0; #else diff --git a/include/linux/pci-tph.h b/include/linux/pci-tph.h index ba28140ce67076..be68cd17f2f833 100644 --- a/include/linux/pci-tph.h +++ b/include/linux/pci-tph.h @@ -25,7 +25,7 @@ int pcie_tph_set_st_entry(struct pci_dev *pdev, unsigned int index, u16 tag); int pcie_tph_get_cpu_st(struct pci_dev *dev, enum tph_mem_type mem_type, - unsigned int cpu_uid, u16 *tag); + unsigned int cpu, u16 *tag); void pcie_disable_tph(struct pci_dev *pdev); int pcie_enable_tph(struct pci_dev *pdev, int mode); u16 pcie_tph_get_st_table_size(struct pci_dev *pdev); @@ -36,7 +36,7 @@ static inline int pcie_tph_set_st_entry(struct pci_dev *pdev, { return -EINVAL; } static inline int pcie_tph_get_cpu_st(struct pci_dev *dev, enum tph_mem_type mem_type, - unsigned int cpu_uid, u16 *tag) + unsigned int cpu, u16 *tag) { return -EINVAL; } static inline void pcie_disable_tph(struct pci_dev *pdev) { } static inline int pcie_enable_tph(struct pci_dev *pdev, int mode)