Merge branch 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull smp fix from Thomas Gleixner:
 "Add warnings to the smp function calls so callers from wrong contexts
  get detected"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  smp: Warn on function calls from softirq context
This commit is contained in:
Linus Torvalds 2019-07-20 10:43:03 -07:00
commit 4b01f5a4c9

View File

@ -291,6 +291,14 @@ int smp_call_function_single(int cpu, smp_call_func_t func, void *info,
WARN_ON_ONCE(cpu_online(this_cpu) && irqs_disabled()
&& !oops_in_progress);
/*
* When @wait we can deadlock when we interrupt between llist_add() and
* arch_send_call_function_ipi*(); when !@wait we can deadlock due to
* csd_lock() on because the interrupt context uses the same csd
* storage.
*/
WARN_ON_ONCE(!in_task());
csd = &csd_stack;
if (!wait) {
csd = this_cpu_ptr(&csd_data);
@ -416,6 +424,14 @@ void smp_call_function_many(const struct cpumask *mask,
WARN_ON_ONCE(cpu_online(this_cpu) && irqs_disabled()
&& !oops_in_progress && !early_boot_irqs_disabled);
/*
* When @wait we can deadlock when we interrupt between llist_add() and
* arch_send_call_function_ipi*(); when !@wait we can deadlock due to
* csd_lock() on because the interrupt context uses the same csd
* storage.
*/
WARN_ON_ONCE(!in_task());
/* Try to fastpath. So, what's a CPU they want? Ignoring this one. */
cpu = cpumask_first_and(mask, cpu_online_mask);
if (cpu == this_cpu)