On Wed, Aug 05, 2020 at 05:08:58PM -0700, Peter Oskolkov wrote:
Thanks for the Cc!
> + * @MEMBARRIER_CMD_PRIVATE_RESTART_RSEQ_ON_CPU:
> + * If a thread belonging to the current process
> + * is currently in an RSEQ critical section on the
> + * CPU identified by flags parameter, restart it.
> + * @flags: if @flags >= 0, identifies the CPU to
> + * restart RSEQ CS on; if == -1, restarts
> + * RSEQ CSs on all CPUs.
> + } else if (cpu_id == -1) {
> + on_each_cpu(membarrier_rseq_ipi,
> + current->group_leader, true);
This is an unpriv IPI the world. That's a big no-no.
Double so because all you want to target is the current process, which
you're defining as CLONE_THREAD, where the rest of this file uses
CLONE_VM to define a process.
