From 2f4b3e8ea202808c6218e2bf67810dfcdb6cb883 Mon Sep 17 00:00:00 2001 From: Grzegorz Jaszczyk Date: Thu, 24 Sep 2026 10:40:20 +0000 Subject: x86/apic: Remove redundant check from x2apic_phys_probe() Commit 9ebd680bd029 ("x86, apic: Use probe routines to simplify apic selection") introduced x2apic_phys_probe() with a generic fallback check for apic == &apic_x2apic_phys to preserve any prior selection of apic_x2apic_phys by default_acpi_madt_oem_check(). At the time, x2apic_acpi_madt_oem_check() only checked x2apic_phys && x2apic_enabled() so that fallback was already redundant. Commit ea0dcf903e7d ("x86/apic: Use x2apic physical mode based on FADT setting") later added the ACPI_FADT_APIC_PHYSICAL check only to x2apic_acpi_madt_oem_check(), temporarily relying on the fallback in x2apic_phys_probe() when x2APIC was pre-enabled by BIOS. Subsequently, cb214ede7657 ("x86/apic: Work around boot failure on HP ProLiant DL980 G7 Server systems") factored out x2apic_fadt_phys() and added it directly to x2apic_phys_probe(). Because default_acpi_madt_oem_check() (via the .acpi_madt_oem_check callback) is the only path that can install apic_x2apic_phys prior to x2apic_phys_probe(), and x2apic_acpi_madt_oem_check() checks the exact same x2apic_phys || x2apic_fadt_phys() condition, the fallback apic == &apic_x2apic_phys check became completely unreachable again. Remove the redundant check and the associated forward declaration of apic_x2apic_phys. In addition to cleaning up dead code, this allows apic_x2apic_phys to be installed as an early boot default driver when hardware x2APIC is pre-enabled without preventing x2apic_cluster from being probed and selected later during boot. [ bp: Massage commit message. ] Signed-off-by: Grzegorz Jaszczyk Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Thomas Gleixner Link: https://patch.msgid.link/20260924104102.3534474-4-jaszczyk@chromium.org --- arch/x86/kernel/apic/x2apic_phys.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) diff --git a/arch/x86/kernel/apic/x2apic_phys.c b/arch/x86/kernel/apic/x2apic_phys.c index 090647cc5a78..5bf86839e84c 100644 --- a/arch/x86/kernel/apic/x2apic_phys.c +++ b/arch/x86/kernel/apic/x2apic_phys.c @@ -6,8 +6,6 @@ #include "local.h" int x2apic_phys; - -static struct apic apic_x2apic_phys; u32 x2apic_max_apicid __ro_after_init = UINT_MAX; void __init x2apic_set_max_apicid(u32 apicid) @@ -110,10 +108,7 @@ static int x2apic_phys_probe(void) if (!x2apic_mode) return 0; - if (x2apic_phys || x2apic_fadt_phys()) - return 1; - - return apic == &apic_x2apic_phys; + return x2apic_phys || x2apic_fadt_phys(); } u32 x2apic_get_apic_id(u32 id) -- cgit v1.2.3