Commit 8312136f authored by Cyrill Gorcunov's avatar Cyrill Gorcunov Committed by Ingo Molnar
Browse files

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: default avatarCyrill Gorcunov <gorcunov@openvz.org>
Cc: "Maciej W. Rozycki" <macro@linux-mips.org>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20090915071230.GA10604@lenovo>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent efc8f741

arch/x86/include/asm/apic.h

+13 −0
Original line number Diff line number Diff line
@@ -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.

 */

arch/x86/kernel/apic/apic.c

+1 −1
Original line number Diff line number Diff line
@@ -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);

arch/x86/kernel/apic/io_apic.c

+2 −2
Original line number Diff line number Diff line
@@ -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);

}

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