From aa63a74d4535a1d97b60e46655a1361c42565b89 Mon Sep 17 00:00:00 2001
From: Tony Luck <tony.luck@intel.com>
Date: Wed, 6 Apr 2022 15:01:50 -0700
Subject: [PATCH] topology/sysfs: Hide PPIN on systems that do not support it.
Systems that do not support a Protected Processor Identification Number
currently report:
# cat /sys/devices/system/cpu/cpu0/topology/ppin
0x0
which is confusing/wrong.
Add a ".is_visible" function to suppress inclusion of the ppin file.
Fixes: ab28e944197f ("topology/sysfs: Add PPIN in sysfs under cpu topology")
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/r/20220406220150.63855-1-tony.luck@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/base/topology.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/drivers/base/topology.c b/drivers/base/topology.c
index e9d1efcda89b..706dbf8bf249 100644
--- a/drivers/base/topology.c
+++ b/drivers/base/topology.c
@@ -152,9 +152,21 @@ static struct attribute *default_attrs[] = {
NULL
};
+static umode_t topology_is_visible(struct kobject *kobj,
+ struct attribute *attr, int unused)
+{
+ struct device *dev = kobj_to_dev(kobj);
+
+ if (attr == &dev_attr_ppin.attr && !topology_ppin(dev->id))
+ return 0;
+
+ return attr->mode;
+}
+
static const struct attribute_group topology_attr_group = {
.attrs = default_attrs,
.bin_attrs = bin_attrs,
+ .is_visible = topology_is_visible,
.name = "topology"
};
--
2.50.1