lkml.org 
[lkml]   [2020]   [Nov]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Subject[PATCH] x86/ioapic: Use I/OAPIC ID for finding irqdomain, not index
From
Date
From: David Woodhouse <dwmw@amazon.co.uk>

In commit b643128b917 ("x86/ioapic: Use irq_find_matching_fwspec() to
find remapping irqdomain") the I/OAPIC code was changed to find its
parent irqdomain using irq_find_matching_fwspec(), but the key used
for the lookup was wrong. It shouldn't use 'ioapic' which is the index
into its own ioapics[] array. It should use the actual arbitration
ID of the I/OAPIC in question, which is mpc_ioapic_id(ioapic).

Fixes: b643128b917 ("x86/ioapic: Use irq_find_matching_fwspec() to find remapping irqdomain")
Reported-by: lkp <oliver.sang@intel.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
---

The X2APIC_OPT_OUT bit was a red herring. Once I spotted and set up a
repro case such that mpc_ioapic_id(N) != N I can see it here.


arch/x86/kernel/apic/io_apic.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 443d2c9086b9..0d68e7c286e2 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2335,14 +2335,14 @@ static int mp_irqdomain_create(int ioapic)
if (cfg->dev) {
fn = of_node_to_fwnode(cfg->dev);
} else {
- fn = irq_domain_alloc_named_id_fwnode("IO-APIC", ioapic);
+ fn = irq_domain_alloc_named_id_fwnode("IO-APIC", mpc_ioapic_id(ioapic));
if (!fn)
return -ENOMEM;
}

fwspec.fwnode = fn;
fwspec.param_count = 1;
- fwspec.param[0] = ioapic;
+ fwspec.param[0] = mpc_ioapic_id(ioapic);

parent = irq_find_matching_fwspec(&fwspec, DOMAIN_BUS_ANY);
if (!parent) {
--
2.17.1
[unhandled content-type:application/x-pkcs7-signature]
\
 
 \ /
  Last update: 2020-11-03 17:37    [W:0.059 / U:0.168 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site