Re: [PATCH][2.5] Honour dont_enable_local_apic flag

[mikpe@csd.uu.se]

Zwane Mwaikambo writes:
 > I agree with doing the clear apic capability flag, Brian how does this 
 > fare? This patch alone should fix it.
 > 
 > Index: linux-2.5/arch/i386/kernel/apic.c
 > ===================================================================
 > RCS file: /home/cvs/linux-2.5/arch/i386/kernel/apic.c,v
 > retrieving revision 1.54
 > diff -u -p -B -r1.54 apic.c
 > --- linux-2.5/arch/i386/kernel/apic.c	31 May 2003 19:01:05 -0000	1.54
 > +++ linux-2.5/arch/i386/kernel/apic.c	2 Jun 2003 03:50:31 -0000
 > @@ -609,7 +609,7 @@ static int __init detect_init_APIC (void
 >  
 >  	/* Disabled by DMI scan or kernel option? */
 >  	if (dont_enable_local_apic)
 > -		return -1;
 > +		goto no_apic;
 >  
 >  	/* Workaround for us being called before identify_cpu(). */
 >  	get_cpu_vendor(&boot_cpu_data);
 > @@ -665,6 +665,7 @@ static int __init detect_init_APIC (void
 >  	return 0;
 >  
 >  no_apic:
 > +	clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
 >  	printk("No local APIC present or hardware disabled\n");
 >  	return -1;
 >  }

Looks good to me. Add a __setup to set dont_enable_local_apic and this
should be sufficient for users of severely broken HW or emulations.