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

[Chris Metcalf]

On 5/18/2016 9:44 AM, Peter Zijlstra wrote:
> 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.

Fair point.  I'll name it task_isolation_deliver_signal() in the next patch series.

> 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.

Well, we do report whatever exception information we have.  For example
a page fault exception will report the address or whatever other info is
handy; it's easy to tune since it's just a vsnprintf of some varargs from the
architecture layer.

For things like IPIs or TLB invalidations or whatever, the code currently just
reports "interrupt"; I could arrange to pass down more informative varargs
from the caller for that as well.  Let me look into it.

--
Chris Metcalf, Mellanox Technologies
http://www.mellanox.com