From 8312136fa8b0a3ec7323bbb1a46be8c0c26e994e Mon Sep 17 00:00:00 2001 From: Cyrill Gorcunov Date: Tue, 15 Sep 2009 11:12:30 +0400 Subject: [PATCH] x86, apic: Fix missed handling of discrete apics In case of discrete (pretty old) apics we may have cpu_has_apic bit not set but have to check if smp_found_config (MP spec) is there and apic was not disabled. Also don't forget to print apic/io-apic for such case as well. Signed-off-by: Cyrill Gorcunov Cc: "Maciej W. Rozycki" Cc: Yinghai Lu LKML-Reference: <20090915071230.GA10604@lenovo> Signed-off-by: Ingo Molnar --- arch/x86/include/asm/apic.h | 13 +++++++++++++ arch/x86/kernel/apic/apic.c | 2 +- arch/x86/kernel/apic/io_apic.c | 4 ++-- 3 files changed, 16 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h index 586b7adb8e53..9a86fb40490d 100644 --- a/arch/x86/include/asm/apic.h +++ b/arch/x86/include/asm/apic.h @@ -65,6 +65,19 @@ static inline void default_inquire_remote_apic(int apicid) __inquire_remote_apic(apicid); } +/* + * With 82489DX we can't rely on apic feature bit + * retrieved via cpuid but still have to deal with + * such an apic chip so we assume that SMP configuration + * is found from MP table (64bit case uses ACPI mostly + * which set smp presence flag as well so we are safe + * to use this helper too). + */ +static inline bool apic_from_smp_config(void) +{ + return smp_found_config && !disable_apic; +} + /* * Basic functions accessing APICs. */ diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index 072aea6c630b..2d59dfa29785 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -978,7 +978,7 @@ void lapic_shutdown(void) { unsigned long flags; - if (!cpu_has_apic) + if (!cpu_has_apic && !apic_from_smp_config()) return; local_irq_save(flags); diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index 3c8f9e75d038..593c4f8a8bb8 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -1863,7 +1863,7 @@ __apicdebuginit(int) print_all_ICs(void) print_PIC(); /* don't print out if apic is not there */ - if (!cpu_has_apic || disable_apic) + if (!cpu_has_apic && !apic_from_smp_config()) return 0; print_all_local_APICs(); @@ -1981,7 +1981,7 @@ void disable_IO_APIC(void) /* * Use virtual wire A mode when interrupt remapping is enabled. */ - if (cpu_has_apic) + if (cpu_has_apic || apic_from_smp_config()) disconnect_bsp_APIC(!intr_remapping_enabled && ioapic_i8259.pin != -1); } -- 2.20.1