Re: IRQ behaivour has been changed from v4.14 to v4.15-rc1

[Thomas Gleixner <tglx@linutronix.de>]

On Thu, 28 Dec 2017, Shevchenko, Andriy wrote:

> Hi!
> 
> Experimenting with AtomISP (yes, code is ugly and MSI handling rather
> hackish, though...).
> 
> So, with v4.14 base:
> 
> [   33.639224] atomisp-isp2 0000:00:03.0: Start stream on pad 1 for asd0
> [   33.652355] atomisp-isp2 0000:00:03.0: irq:0x20
> [   33.662456] atomisp-isp2 0000:00:03.0: irq:0x20
> [   33.698064] atomisp-isp2 0000:00:03.0: stream[0] started.
> 
> Ctrl+C
> 
> [   48.185643] atomisp-isp2 0000:00:03.0: <atomisp_dqbuf: -512
> [   48.204641] atomisp-isp2 0000:00:03.0: release device ATOMISP ISP
> CAPTURE output
> ...
> 
> and machine still alive.
> 
> 
> With v4.15-rc1 base (basically your branch + some my hack patches) the
> IR
> Q behaviour changed, i.e. I have got:
> 
> 
> [   85.167061] spurious APIC interrupt through vector ff on CPU#0,
> should never happen.
> [   85.199886] atomisp-isp2 0000:00:03.0: stream[0] started.
> 
> and Ctrl+C does NOT work. Machine just hangs.
> 
> It might be related to this:
> https://lkml.org/lkml/2017/12/22/697

I don't think so.

Does the patch below cure it?

Thanks,

	tglx
8<-----------------
 arch/x86/kernel/apic/apic_flat_64.c   |    2 +-
 arch/x86/kernel/apic/probe_32.c       |    2 +-
 arch/x86/kernel/apic/x2apic_cluster.c |    2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

--- 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,