[PATCH v2 2/2] virt: acrn: Make remove_cpu sysfs invisible with !CONFIG_HOTPLUG_CPU

From: shuo . a . liu
Date: Fri Feb 12 2021 - 11:56:45 EST


From: Shuo Liu <shuo.a.liu@xxxxxxxxx>

Without cpu hotplug support, vCPU cannot be removed from a Service VM.
Don't expose remove_cpu sysfs when CONFIG_HOTPLUG_CPU disabled.

Signed-off-by: Shuo Liu <shuo.a.liu@xxxxxxxxx>
---
drivers/virt/acrn/hsm.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/drivers/virt/acrn/hsm.c b/drivers/virt/acrn/hsm.c
index 1f6b7c54a1a4..6996ea6219e5 100644
--- a/drivers/virt/acrn/hsm.c
+++ b/drivers/virt/acrn/hsm.c
@@ -404,6 +404,14 @@ static ssize_t remove_cpu_store(struct device *dev,
}
static DEVICE_ATTR_WO(remove_cpu);

+static umode_t acrn_attr_visible(struct kobject *kobj, struct attribute *a, int n)
+{
+ if (a == &dev_attr_remove_cpu.attr)
+ return IS_ENABLED(CONFIG_HOTPLUG_CPU) ? a->mode : 0;
+
+ return a->mode;
+}
+
static struct attribute *acrn_attrs[] = {
&dev_attr_remove_cpu.attr,
NULL
@@ -411,6 +419,7 @@ static struct attribute *acrn_attrs[] = {

static struct attribute_group acrn_attr_group = {
.attrs = acrn_attrs,
+ .is_visible = acrn_attr_visible,
};

static const struct attribute_group *acrn_attr_groups[] = {
--
2.28.0