[patch V4 14/41] x86/apic: Use BAD_APICID consistently

Thomas Gleixner
2023-08-14T08:55:37Z

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.

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>

---
V3: Fixed changelog typos - Sohil
---
arch/x86/kernel/acpi/boot.c | 2 +-
arch/x86/kernel/apic/apic.c | 6 ++----
2 files changed, 3 insertions(+), 5 deletions(-)

--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -852,7 +852,7 @@ int acpi_unmap_cpu(int cpu)
set_apicid_to_node(per_cpu(x86_cpu_to_apicid, cpu), NUMA_NO_NODE);
#endif

- per_cpu(x86_cpu_to_apicid, cpu) = -1;
+ per_cpu(x86_cpu_to_apicid, cpu) = BAD_APICID;
set_cpu_present(cpu, false);
num_processors--;

--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -72,7 +72,7 @@ unsigned int num_processors;
unsigned disabled_cpus;

/* Processor that is doing the boot up */
-unsigned int boot_cpu_physical_apicid __ro_after_init = -1U;
+unsigned int boot_cpu_physical_apicid __ro_after_init = BAD_APICID;
EXPORT_SYMBOL_GPL(boot_cpu_physical_apicid);

u8 boot_cpu_apic_version __ro_after_init;
@@ -2318,9 +2318,7 @@ static int nr_logical_cpuids = 1;
/*
* Used to store mapping between logical CPU IDs and APIC IDs.
*/
-int cpuid_to_apicid[] = {
- [0 ... NR_CPUS - 1] = -1,
-};
+int cpuid_to_apicid[] = { [0 ... NR_CPUS - 1] = BAD_APICID, };

bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
{