Re: [PATCH v12 06/13] task_isolation: support PR_TASK_ISOLATION_STRICT mode

[Peter Zijlstra]

On Tue, Apr 05, 2016 at 01:38:35PM -0400, Chris Metcalf wrote:
> +void task_isolation_interrupt(struct task_struct *task, const char *buf)
> +{
> +	siginfo_t info = {};
> +	int sig;
> +
> +	pr_warn("%s/%d: task_isolation strict mode violated by %s\n",
> +		task->comm, task->pid, buf);
> +

So the function name suggests this is called for interrupts, except its
purpose is to deliver a signal.

Now, in case of exceptions the violation isn't necessarily _by_ the task
itself. You might want to change that to report the exception
type/number instead of the affected task.

> +	/* Get the signal number to use. */
> +	sig = PR_TASK_ISOLATION_GET_SIG(task->task_isolation_flags);
> +	if (sig == 0)
> +		sig = SIGKILL;
> +	info.si_signo = sig;
> +
> +	/*
> +	 * Turn off task isolation mode entirely to avoid spamming
> +	 * the process with signals.  It can re-enable task isolation
> +	 * mode in the signal handler if it wants to.
> +	 */
> +	task_isolation_set_flags(task, 0);
> +
> +	send_sig_info(sig, &info, task);
> +}