[patch V3 14/60] x86/apic: Split register_apic_address()

From: Thomas Gleixner
Date: Tue Aug 01 2023 - 06:47:51 EST


Split the fixmap setup out of register_lapic_address() and reuse it when
the X2APIC is disabled during setup.

This avoids that the APIC ID is registered twice.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
arch/x86/kernel/apic/apic.c | 22 ++++++++++++++--------
1 file changed, 14 insertions(+), 8 deletions(-)

--- 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();
}

/*