From: Jan Beulich <jbeulich@suse.com>
Date: Thu, 12 Nov 2015 16:04:10 +0000 (+0100)
Subject: x86/IO-APIC: fix setup of Xen internally used IRQs
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~2275
X-Git-Url: https://dgit.raspbian.org/%22http:/www.example.com/cgi/%22https:/%22bookmarks://%22Dat/%22http:/www.example.com/cgi/%22https:/%22bookmarks:/%22Dat?a=commitdiff_plain;h=1126b40892ab56cb13c3cae5822bf3a18a689ffb;p=xen.git

x86/IO-APIC: fix setup of Xen internally used IRQs

..., i.e. namely that of a PCI serial card with an IRQ above the
legacy range. This had got broken by the switch to cpumask_any() in
cpu_mask_to_apicid_phys(). Fix this by allowing all CPUs for that IRQ
(such that __setup_vector_irq() will properly update a booting CPU's
vector_irq[], avoiding "No irq handler for vector" messages and the
interrupt not working).

While doing this I also noticed that io_apic_set_pci_routing() can't
be quite right: It sets up the destination _before_ getting a vector
allocated (which on other than systems using the flat APIC mode
affects the possible destinations), and also didn't restrict affinity
to ->arch.cpu_mask (as established by assign_irq_vector()).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
---

diff --git a/xen/arch/x86/io_apic.c b/xen/arch/x86/io_apic.c
index 1e710d6817..f5b8d7d006 100644
--- a/xen/arch/x86/io_apic.c
+++ b/xen/arch/x86/io_apic.c
@@ -2201,6 +2201,7 @@ int io_apic_set_pci_routing (int ioapic, int pin, int irq, int edge_level, int a
 {
     struct irq_desc *desc = irq_to_desc(irq);
     struct IO_APIC_route_entry entry;
+    cpumask_t mask;
     unsigned long flags;
     int vector;
 
@@ -2220,8 +2221,6 @@ int io_apic_set_pci_routing (int ioapic, int pin, int irq, int edge_level, int a
 
     entry.delivery_mode = INT_DELIVERY_MODE;
     entry.dest_mode = INT_DEST_MODE;
-    SET_DEST(entry.dest.dest32, entry.dest.logical.logical_dest,
-        cpu_mask_to_apicid(TARGET_CPUS));
     entry.trigger = edge_level;
     entry.polarity = active_high_low;
     entry.mask  = 1;
@@ -2237,6 +2236,10 @@ int io_apic_set_pci_routing (int ioapic, int pin, int irq, int edge_level, int a
         return vector;
     entry.vector = vector;
 
+    cpumask_and(&mask, desc->arch.cpu_mask, TARGET_CPUS);
+    SET_DEST(entry.dest.dest32, entry.dest.logical.logical_dest,
+             cpu_mask_to_apicid(&mask));
+
     apic_printk(APIC_DEBUG, KERN_DEBUG "IOAPIC[%d]: Set PCI routing entry "
 		"(%d-%d -> %#x -> IRQ %d Mode:%i Active:%i)\n", ioapic,
 		mp_ioapics[ioapic].mpc_apicid, pin, entry.vector, irq,
diff --git a/xen/arch/x86/smpboot.c b/xen/arch/x86/smpboot.c
index dabc929d4c..1d884afde2 100644
--- a/xen/arch/x86/smpboot.c
+++ b/xen/arch/x86/smpboot.c
@@ -1084,7 +1084,7 @@ void __init smp_intr_init(void)
         vector = alloc_hipriority_vector();
         per_cpu(vector_irq, cpu)[vector] = irq;
         irq_to_desc(irq)->arch.vector = vector;
-        cpumask_copy(irq_to_desc(irq)->arch.cpu_mask, &cpu_online_map);
+        cpumask_setall(irq_to_desc(irq)->arch.cpu_mask);
     }
 
     /* Direct IPI vectors. */