On Mon, Oct 12 2020 at 21:20, David Woodhouse wrote:
> On Mon, 2020-10-12 at 20:38 +0200, Thomas Gleixner wrote:
>> Nasty, but way better than what we have now.
>
> Want me to send that out in email or is the git tree enough for now?
>
> I've cleaned it up a little and fixed a bug in the I/OAPIC error path.
Mail would be nice once you are confident with the pile.
> Still not entirely convinced about the apic->apic_id_valid(32768) thing
> but it should work well enough, and doesn't require exporting any extra
> state from apic.c that way.
Yeah, that part is odd.
I really dislike the way how irq_find_matching_fwspec() works. The 'rc'
value is actually boolean despite being type 'int' and if 'rc' is not 0
then it returns the domain even if 'rc' is an error code.
But that does not allow to return error codes from a domain match() /
select() callback which is what we really want to express that there is
something fishy.
Something like the below perhaps? Needs more thought obviously.
Marc, any opinion ?
Thanks,
tglx
8<-------------
arch/x86/kernel/apic/vector.c | 18 ++++++++++++++++++
include/linux/irqdomain.h | 1 +
kernel/irq/irqdomain.c | 2 +-
3 files changed, 20 insertions(+), 1 deletion(-)
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -593,6 +593,24 @@ static int x86_vector_alloc_irqs(struct
return err;
}
+struct irq_domain *x86_select_parent_domain(struct irq_fwspec *fwspec)
+{
+ struct irq_domain *dom;
+
+ /*
+ * If Interrupt Remapping is enabled then the match function
+ * returns either the remapping domain or an error code if the
+ * device is not registered with the remapping unit.
+ *
+ * If remapping is not enabled, then the function returns NULL.
+ */
+ dom = irq_find_matching_fwspec(fwspec, DOMAIN_BUS_IR);
+ if (dom)
+ return IS_ERR(dom) ? NULL : dom;
+
+ return x86_vector_domain;
+}
+
#ifdef CONFIG_GENERIC_IRQ_DEBUGFS
static void x86_vector_debug_show(struct seq_file *m, struct irq_domain *d,
struct irq_data *irqd, int ind)
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -85,6 +85,7 @@ enum irq_domain_bus_token {
DOMAIN_BUS_TI_SCI_INTA_MSI,
DOMAIN_BUS_WAKEUP,
DOMAIN_BUS_VMD_MSI,
+ DOMAIN_BUS_IR,
};
/**
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -395,7 +395,7 @@ struct irq_domain *irq_find_matching_fws
(h->bus_token == bus_token)));
if (rc) {
- found = h;
+ found = rc < 0 ? ERR_PTR(rc) : h;
break;
}
}
