From 6d2d49d2cd0199ce298d111ee7fd405af3344a70 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 15 Jan 2015 21:22:27 +0000 Subject: [PATCH] x86/x2apic: Use state information for disable Use the state information to simplify the disable logic further. Signed-off-by: Thomas Gleixner Acked-by: Borislav Petkov Cc: Jiang Liu Cc: Joerg Roedel Cc: Tony Luck Link: http://lkml.kernel.org/r/20150115211703.209387598@linutronix.de Signed-off-by: Thomas Gleixner --- arch/x86/kernel/apic/apic.c | 26 ++++++++++---------------- 1 file changed, 10 insertions(+), 16 deletions(-) diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index 0ee96b9fe4e6..0c554f5d03a6 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -1547,26 +1547,20 @@ void x2apic_setup(void) static __init void x2apic_disable(void) { - u64 msr; - - if (!cpu_has_x2apic) - return; - - rdmsrl(MSR_IA32_APICBASE, msr); - if (msr & X2APIC_ENABLE) { - u32 x2apic_id = read_apic_id(); + u32 x2apic_id; - if (x2apic_id >= 255) - panic("Cannot disable x2apic, id: %08x\n", x2apic_id); + if (x2apic_state != X2APIC_ON) + goto out; - __x2apic_disable(); - - x2apic_mode = 0; - - register_lapic_address(mp_lapic_addr); - } + x2apic_id = read_apic_id(); + if (x2apic_id >= 255) + panic("Cannot disable x2apic, id: %08x\n", x2apic_id); + __x2apic_disable(); + register_lapic_address(mp_lapic_addr); +out: x2apic_state = X2APIC_DISABLED; + x2apic_mode = 0; } static __init void x2apic_enable(void) -- 2.34.1