From 5a88f354dcd8f19436bbda52f075276a5c70424f Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 8 Aug 2023 15:03:48 -0700 Subject: [PATCH] x86/apic: Split register_apic_address() Split the fixmap setup out of register_lapic_address() and reuse it when the X2APIC is disabled during setup. This avoids registering the APIC ID (setting 'mp_lapic_addr') twice. [ dhansen: changelog wording tweak ] Signed-off-by: Thomas Gleixner Signed-off-by: Dave Hansen Acked-by: Peter Zijlstra (Intel) Tested-by: Michael Kelley Tested-by: Sohil Mehta Tested-by: Juergen Gross # Xen PV (dom0 and unpriv. guest) --- arch/x86/kernel/apic/apic.c | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index d0f4cca303788..45ae178b9e50e 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -1852,6 +1852,8 @@ void x2apic_setup(void) __x2apic_enable(); } +static __init void apic_set_fixmap(void); + static __init void x2apic_disable(void) { u32 x2apic_id, state = x2apic_state; @@ -1872,7 +1874,7 @@ static __init void x2apic_disable(void) } __x2apic_disable(); - register_lapic_address(mp_lapic_addr); + apic_set_fixmap(); } static __init void x2apic_enable(void) @@ -2145,17 +2147,21 @@ void __init init_apic_mappings(void) } } +static __init void apic_set_fixmap(void) +{ + set_fixmap_nocache(FIX_APIC_BASE, mp_lapic_addr); + apic_mmio_base = APIC_BASE; + apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n", + apic_mmio_base, mp_lapic_addr); + apic_read_boot_cpu_id(false); +} + void __init register_lapic_address(unsigned long address) { mp_lapic_addr = address; - if (x2apic_mode) - return; - - set_fixmap_nocache(FIX_APIC_BASE, address); - apic_mmio_base = APIC_BASE; - apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n", APIC_BASE, address); - apic_read_boot_cpu_id(false); + if (!x2apic_mode) + apic_set_fixmap(); } /*