[PATCH] x86/pci: insert ioapic resource before assign unassignedresource for pci -v2

From: Yinghai Lu
Date: Fri Jul 10 2009 - 12:37:37 EST



Stephen reported that his DL585 G2 need noapic after 2.6.22 (?)

Dann bisected
--------------------------------------------------------------------
commit 30a18d6c3f1e774de656ebd8ff219d53e2ba4029
Date: Tue Feb 19 03:21:20 2008 -0800

x86: multi pci root bus with different io resource range, on
64-bit
--------------------------------------------------------------------
caused the problem.

it turns out that
1. that AMD-based system has two HT chains.
2. BIOS doesn't allocate resource for BAR 6 of devices under 8132 etc
3. that multi-peer-root patche will try to split root resource to peer
root resources according to pci conf of NB
4. pci assign unassigned code assign some range to pci-x bridge, but it
is overlapping BAR that are used by ioapic addr of io4 and 8132.

the reason: at that point ioapic address are not inserted yet.

aka that patch is not the cause, and it just uncover other problems.

solution is trying to insert ioapic_resource early a little bit.

v2: update comments

Reported-by: Stephen Frost <sfrost@xxxxxxxxxxx>
Reported-and-Tested-by: dann frazier <dannf@xxxxxx>
Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
Cc: stable@xxxxxxxxxx

---
arch/x86/include/asm/io_apic.h | 2 ++
arch/x86/kernel/apic/io_apic.c | 14 +++-----------
arch/x86/pci/i386.c | 7 +++++++
3 files changed, 12 insertions(+), 11 deletions(-)

Index: linux-2.6/arch/x86/include/asm/io_apic.h
===================================================================
--- linux-2.6.orig/arch/x86/include/asm/io_apic.h
+++ linux-2.6/arch/x86/include/asm/io_apic.h
@@ -161,6 +161,7 @@ extern int io_apic_set_pci_routing(struc
struct io_apic_irq_attr *irq_attr);
extern int (*ioapic_renumber_irq)(int ioapic, int irq);
extern void ioapic_init_mappings(void);
+extern void ioapic_insert_resources(void);

extern struct IO_APIC_route_entry **alloc_ioapic_entries(void);
extern void free_ioapic_entries(struct IO_APIC_route_entry **ioapic_entries);
@@ -180,6 +181,7 @@ extern void ioapic_write_entry(int apic,
#define io_apic_assign_pci_irqs 0
static const int timer_through_8259 = 0;
static inline void ioapic_init_mappings(void) { }
+static inline void ioapic_insert_resources(void) { }

static inline void probe_nr_irqs_gsi(void) { }
#endif
Index: linux-2.6/arch/x86/kernel/apic/io_apic.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/apic/io_apic.c
+++ linux-2.6/arch/x86/kernel/apic/io_apic.c
@@ -4181,28 +4181,20 @@ fake_ioapic_page:
}
}

-static int __init ioapic_insert_resources(void)
+void __init ioapic_insert_resources(void)
{
int i;
struct resource *r = ioapic_resources;

if (!r) {
- if (nr_ioapics > 0) {
+ if (nr_ioapics > 0)
printk(KERN_ERR
"IO APIC resources couldn't be allocated.\n");
- return -1;
- }
- return 0;
+ return;
}

for (i = 0; i < nr_ioapics; i++) {
insert_resource(&iomem_resource, r);
r++;
}
-
- return 0;
}
-
-/* Insert the IO APIC resources after PCI initialization has occured to handle
- * IO APICS that are mapped in on a BAR in PCI space. */
-late_initcall(ioapic_insert_resources);
Index: linux-2.6/arch/x86/pci/i386.c
===================================================================
--- linux-2.6.orig/arch/x86/pci/i386.c
+++ linux-2.6/arch/x86/pci/i386.c
@@ -35,6 +35,7 @@
#include <asm/pat.h>
#include <asm/e820.h>
#include <asm/pci_x86.h>
+#include <asm/io_apic.h>


static int
@@ -227,6 +228,12 @@ void __init pcibios_resource_survey(void
pcibios_allocate_resources(1);

e820_reserve_resources_late();
+ /*
+ * Insert the IO APIC resources after PCI initialization has
+ * occured to handle IO APICS that are mapped in on a BAR in
+ * PCI space, but before trying to assign unassigned pci res.
+ */
+ ioapic_insert_resources();
}

/**
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