Re: [PATCH v2 1/3] livepatch: Add force sysfs attribute

From: Josh Poimboeuf
Date: Fri Aug 11 2017 - 17:13:29 EST


On Thu, Aug 10, 2017 at 12:48:13PM +0200, Miroslav Benes wrote:
> +static ssize_t force_store(struct kobject *kobj, struct kobj_attribute *attr,
> + const char *buf, size_t count)
> +{
> + /*
> + * klp_mutex lock is not grabbed here intentionally. It is not really
> + * needed. The race window is harmless and grabbing the lock would only
> + * hold the action back.
> + */
> + if (!klp_transition_patch) {
> + pr_info("no patching in progress, forced action ineffective\n");
> + return -EINVAL;
> + }
> +
> + return -EINVAL;
> +}

I think this is really a minor issue, and the -EINVAL is enough. As the
comment says, the race window is harmless. So I'd say there's no need
to scare the user with a printk.

--
Josh