Re: panic from vector domain patch (was RE: Linus' tree broken?)

Kenji Kaneshige
2007-07-25T08:59:22Z

Doug,

2007-07-25 (水) の 01:09 -0400 に Doug Chapman さんは書きました:
> Yasuaki,
>
> I added a bunch of printk's to try to better understand this.
> ia64_mv.setup does get initialized properly but then gets overwritten.
> It appears that it gets overwritten in __bind_irq_vector but I have not
> narrowed down exactly where. I put a printk at the top and bottom of
> this function to show what ia64_mv.setup is and I am finding that on the
> 3rd call to this function it causes ia64_mv.setup to get set to -1.
>
> It is getting way too late for me (1AM here). I will try to dig into
> this more tomorrow but at least I have narrowed it down to a bit of code
> that actually is touched by the commit that causes the panic.
>
> - Doug

I found a bug which causes wrong access to vector_table[] array.
I guess ia64_mv.setup was destroyed by this. Could you try the
attached patch?

Thanks,
Kenji Kaneshige
---

Fix wrong access to vector_table[].

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>

---
arch/ia64/kernel/irq_ia64.c | 21 ++++++++++-----------
1 files changed, 10 insertions(+), 11 deletions(-)

Index: linux-2.6.23-rc1/arch/ia64/kernel/irq_ia64.c
=================================--- linux-2.6.23-rc1.orig/arch/ia64/kernel/irq_ia64.c
+++ linux-2.6.23-rc1/arch/ia64/kernel/irq_ia64.c
@@ -85,8 +85,8 @@ DEFINE_PER_CPU(int[IA64_NUM_VECTORS], ve
[0 ... IA64_NUM_VECTORS - 1] = IA64_SPURIOUS_INT_VECTOR
};

-static cpumask_t vector_table[IA64_MAX_DEVICE_VECTORS] = {
- [0 ... IA64_MAX_DEVICE_VECTORS - 1] = CPU_MASK_NONE
+static cpumask_t vector_table[IA64_NUM_VECTORS] = {
+ [0 ... IA64_NUM_VECTORS - 1] = CPU_MASK_NONE
};

static int irq_status[NR_IRQS] = {
@@ -123,17 +123,18 @@ static inline int find_unassigned_irq(vo
static inline int find_unassigned_vector(cpumask_t domain)
{
cpumask_t mask;
- int pos;
+ int pos, vector;

cpus_and(mask, domain, cpu_online_map);
if (cpus_empty(mask))
return -EINVAL;

for (pos = 0; pos < IA64_NUM_DEVICE_VECTORS; pos++) {
- cpus_and(mask, domain, vector_table[pos]);
+ vector = IA64_FIRST_DEVICE_VECTOR + pos;
+ cpus_and(mask, domain, vector_table[vector]);
if (!cpus_empty(mask))
continue;
- return IA64_FIRST_DEVICE_VECTOR + pos;
+ return vector;
}
return -ENOSPC;
}
@@ -141,7 +142,7 @@ static inline int find_unassigned_vector
static int __bind_irq_vector(int irq, int vector, cpumask_t domain)
{
cpumask_t mask;
- int cpu, pos;
+ int cpu;
struct irq_cfg *cfg = &irq_cfg[irq];

cpus_and(mask, domain, cpu_online_map);
@@ -156,8 +157,7 @@ static int __bind_irq_vector(int irq, in
cfg->vector = vector;
cfg->domain = domain;
irq_status[irq] = IRQ_USED;
- pos = vector - IA64_FIRST_DEVICE_VECTOR;
- cpus_or(vector_table[pos], vector_table[pos], domain);
+ cpus_or(vector_table[vector], vector_table[vector], domain);
return 0;
}

@@ -174,7 +174,7 @@ int bind_irq_vector(int irq, int vector,

static void __clear_irq_vector(int irq)
{
- int vector, cpu, pos;
+ int vector, cpu;
cpumask_t mask;
cpumask_t domain;
struct irq_cfg *cfg = &irq_cfg[irq];
@@ -189,8 +189,7 @@ static void __clear_irq_vector(int irq)
cfg->vector = IRQ_VECTOR_UNASSIGNED;
cfg->domain = CPU_MASK_NONE;
irq_status[irq] = IRQ_UNUSED;
- pos = vector - IA64_FIRST_DEVICE_VECTOR;
- cpus_andnot(vector_table[pos], vector_table[pos], domain);
+ cpus_andnot(vector_table[vector], vector_table[vector], domain);
}

static void clear_irq_vector(int irq)