PROBLEM: 4.15.0-rc3 APIC causes lockups on Core 2 Duo laptop

[Thomas Gleixner]

On Wed, 20 Dec 2017, Alexandru Chirvasitu wrote:
> On Wed, Dec 20, 2017 at 11:58:57AM +0800, Dou Liyang wrote:
> > At 12/20/2017 08:31 AM, Thomas Gleixner wrote:
> > > > I had never heard of 'bisect' before this casual mention (you might tell
> > > > I am a bit out of my depth). I've since applied it to Linus' tree between
> > > 
> > > > bebc608 Linux 4.14 (good)
> > > > 
> > > > and
> > > > 
> > > > 4fbd8d1 Linux 4.15-rc1 (bad)
> > > 
> > > Is Linus current head 4.15-rc4 bad as well?
> > > 
> > [...]
> 
> Yes. Exactly the same symptoms on
> 
> 1291a0d5 Linux 4.15-rc4
> 
> compiled just now from Linus' tree. 

Ok, lets take a step back. The bisect/kexec attempts led us away from the
initial problem which is the machine locking up after login, right?

Could you try the patch below on top of Linus tree (rc5+)?

Thanks,

	tglx

8<---------------
--- a/arch/x86/kernel/apic/apic_flat_64.c
+++ b/arch/x86/kernel/apic/apic_flat_64.c
@@ -151,7 +151,7 @@ static struct apic apic_flat __ro_after_
 	.apic_id_valid			= default_apic_id_valid,
 	.apic_id_registered		= flat_apic_id_registered,
 
-	.irq_delivery_mode		= dest_LowestPrio,
+	.irq_delivery_mode		= dest_Fixed,
 	.irq_dest_mode			= 1, /* logical */
 
 	.disable_esr			= 0,
--- a/arch/x86/kernel/apic/probe_32.c
+++ b/arch/x86/kernel/apic/probe_32.c
@@ -105,7 +105,7 @@ static struct apic apic_default __ro_aft
 	.apic_id_valid			= default_apic_id_valid,
 	.apic_id_registered		= default_apic_id_registered,
 
-	.irq_delivery_mode		= dest_LowestPrio,
+	.irq_delivery_mode		= dest_Fixed,
 	/* logical delivery broadcast to all CPUs: */
 	.irq_dest_mode			= 1,
 
--- a/arch/x86/kernel/apic/x2apic_cluster.c
+++ b/arch/x86/kernel/apic/x2apic_cluster.c
@@ -184,7 +184,7 @@ static struct apic apic_x2apic_cluster _
 	.apic_id_valid			= x2apic_apic_id_valid,
 	.apic_id_registered		= x2apic_apic_id_registered,
 
-	.irq_delivery_mode		= dest_LowestPrio,
+	.irq_delivery_mode		= dest_Fixed,
 	.irq_dest_mode			= 1, /* logical */
 
 	.disable_esr			= 0,