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[PATCH] Do not enforce unique IO_APIC_ID check for xAPIC systems (i386)

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This patch is per Andi's request to remove NO_IOAPIC_CHECK from genapic and
use heuristics to prevent unique I/O APIC ID check for systems that don't
need it.  The patch disables unique I/O APIC ID check for Xeon-based and
other platforms that don't use serial APIC bus for interrupt delivery.
Andi stated that AMD systems don't need unique IO_APIC_IDs either.

Signed-off-by: Natalie Protasevich <Natalie.Protasevich@unisys.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Natalie Protasevich
2005-06-23 00:08:22 -07:00
committed by Linus Torvalds
parent 7c1def1652
commit ca05fea6db
10 changed files with 10 additions and 19 deletions
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10
arch/i386/kernel/io_apic.c
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@@ -1658,6 +1658,12 @@ static void __init setup_ioapic_ids_from_mpc(void)
unsigned char old_id;
unsigned long flags;
/*
* Don't check I/O APIC IDs for xAPIC systems. They have
* no meaning without the serial APIC bus.
*/
if (!(boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && boot_cpu_data.x86 < 15))
return;
/*
* This is broken; anything with a real cpu count has to
* circumvent this idiocy regardless.
@@ -1684,10 +1690,6 @@ static void __init setup_ioapic_ids_from_mpc(void)
mp_ioapics[apic].mpc_apicid = reg_00.bits.ID;
}
/* Don't check I/O APIC IDs for some xAPIC systems. They have
* no meaning without the serial APIC bus. */
if (NO_IOAPIC_CHECK)
continue;
/*
* Sanity check, is the ID really free? Every APIC in a
* system must have a unique ID or we get lots of nice