Re: [patch 3/4] Locally disable the softlockup watchdog rather than touching it

[Prarit Bhargava <prarit@redhat.com>]

>> touch_nmi_watchdog is attempting to tickle _all_ CPUs softlockup watchdogs.
>>     
>
> It is supposed to only touch the current CPU, just like it only touches
> the NMI watchdog on the current CPU.
>
>   

Andi,

(sorry for the cut-and-paste). 

touch_nmi_watchdogs sets EACH CPUs alert_counter to 0.

void touch_nmi_watchdog (void)
{
        if (nmi_watchdog > 0) {
                unsigned cpu;

                /*
                 * Just reset the alert counters, (other CPUs might be
                 * spinning on locks we hold):
                 */
                for_each_present_cpu (cpu)
                        alert_counter[cpu] = 0;
        }

        /*
         * Tickle the softlockup detector too:
         */
        touch_softlockup_watchdog();
}

The call to touch_softlockup_watchdog here is incorrect -- it is only 
touching the current CPU's softlockup.

P.