Hi,
On Tue 23.Feb'21 at 15:25:30 +0000, Qais Yousef wrote:
On 02/21/21 21:43, shuo.a....@intel.com wrote:
From: Shuo Liu <shuo.a....@intel.com>
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....@intel.com>
Acked-by: Randy Dunlap <rdun...@infradead.org> # build-tested
Cc: Stephen Rothwell <s...@canb.auug.org.au>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Cc: Qais Yousef <qais.you...@arm.com>
---
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;
+}
+
I can't find this code in Linus' master. But this looks fine from my narrow
Now, the code is still in linux-next tree only.
PoV. Protecting the attribute with ifdef CONFIG_HOTPLUG_CPU is easier to read
for me, but this doesn't mean this approach is not fine.
Just FYI, Greg prefers this solution.
https://lore.kernel.org/lkml/20210212045724.77846-1-shuo.a....@intel.com/
Thanks
shuo
