Commit 3cfe889f authored by Chengwen Feng's avatar Chengwen Feng Committed by Rafael J. Wysocki
Browse files

x86/acpi: Add acpi_get_cpu_uid() for unified ACPI CPU UID retrieval 



As a step towards unifying the interface for retrieving ACPI CPU UID
across architectures, introduce a new function acpi_get_cpu_uid() for
x86. While at it, add input validation to make the code more robust.

Update Xen-related code to use acpi_get_cpu_uid() instead of the legacy
cpu_acpi_id() function, and remove the now-unused cpu_acpi_id() to clean
up redundant code.

Signed-off-by: default avatarChengwen Feng <fengchengwen@huawei.com>
Reviewed-by: default avatarJonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: default avatarJuergen Gross <jgross@suse.com>
Link: https://patch.msgid.link/20260401081640.26875-5-fengchengwen@huawei.com


Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 0c823199

arch/x86/include/asm/acpi.h

+2 −0
Original line number Diff line number Diff line
@@ -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)

{

arch/x86/include/asm/cpu.h

+0 −1
Original line number Diff line number Diff line
@@ -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

arch/x86/include/asm/smp.h

+0 −1
Original line number Diff line number Diff line
@@ -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

arch/x86/kernel/acpi/boot.c

+20 −0
Original line number Diff line number Diff line
@@ -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);

arch/x86/xen/enlighten_hvm.c

+3 −2
Original line number Diff line number Diff line
@@ -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);