@@ -94,16 +94,28 @@ static void machine_crash_nonpanic_core(void *unused)
}
}
+static DEFINE_PER_CPU(call_single_data_t, cpu_stop_csd) =
+ CSD_INIT(machine_crash_nonpanic_core, NULL);
+
void crash_smp_send_stop(void)
{
static int cpus_stopped;
unsigned long msecs;
+ call_single_data_t *csd;
+ int cpu, this_cpu = raw_smp_processor_id();
if (cpus_stopped)
return;
atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
- smp_call_function(machine_crash_nonpanic_core, NULL, false);
+ for_each_online_cpu(cpu) {
+ if (cpu == this_cpu)
+ continue;
+
+ csd = &per_cpu(cpu_stop_csd, cpu);
+ smp_call_function_single_async(cpu, csd);
+ }
+
msecs = 1000; /* Wait at most a second for the other cpus to stop */
while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
mdelay(1);
If a panic is triggered by a hrtimer interrupt all online cpus will be notified and set offline. But as highlighted by commit 19dbdcb8039c ("smp: Warn on function calls from softirq context") this call should not be made synchronous with disabled interrupts: softdog: Initiating panic Kernel panic - not syncing: Software Watchdog Timer expired WARNING: CPU: 1 PID: 0 at kernel/smp.c:753 smp_call_function_many_cond unwind_backtrace: show_stack dump_stack_lvl __warn warn_slowpath_fmt smp_call_function_many_cond smp_call_function crash_smp_send_stop.part.0 machine_crash_shutdown __crash_kexec panic softdog_fire __hrtimer_run_queues hrtimer_interrupt Make the smp call for machine_crash_nonpanic_core() asynchronous. Signed-off-by: Mårten Lindahl <marten.lindahl@axis.com> --- Changes in v2: - Fixed commit msg typo "noitfied" => "notified" - Link to v1: https://lore.kernel.org/r/20230615-arm-smp-call-async-v1-1-58f4afb20f0f@axis.com --- arch/arm/kernel/machine_kexec.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) --- base-commit: 52a93d39b17dc7eb98b6aa3edb93943248e03b2f change-id: 20230807-arm-smp-call-async-4c1da2de9621 Best regards,