Messages in this thread | | | Date | Thu, 6 Aug 2020 15:48:28 +0200 | From | peterz@infradea ... | Subject | Re: [PATCH 1/2] membarrier: add MEMBARRIER_CMD_PRIVATE_RESTART_RSEQ_ON_CPU |
| |
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.
| |