sparc: Touch NMI watchdog when walking cpus and calling printk

commit 31aaa98c248da766ece922bbbe8cc78cfd0bc920 upstream.

With the increase in number of CPUs calls to functions that dump
output to console (e.g., arch_trigger_all_cpu_backtrace) can take
a long time to complete. If IRQs are disabled eventually the NMI
watchdog kicks in and creates more havoc. Avoid by telling the NMI
watchdog everything is ok.

Signed-off-by: David Ahern <david.ahern@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c
index 0be7bf978cb1da03b8d657958ec6d0ec3c4e7d8b..46a59643bb1cee71edbd3d91d3f8f2eb09b3a26a 100644 (file)
--- a/arch/sparc/kernel/process_64.c
+++ b/arch/sparc/kernel/process_64.c
@@ -287,6 +287,8 @@ void arch_trigger_all_cpu_backtrace(bool include_self)
                        printk("             TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
                               gp->tpc, gp->o7, gp->i7, gp->rpc);
                }
+
+               touch_nmi_watchdog();
        }
 
        memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
@@ -362,6 +364,8 @@ static void pmu_snapshot_all_cpus(void)
                       (cpu == this_cpu ? '*' : ' '), cpu,
                       pp->pcr[0], pp->pcr[1], pp->pcr[2], pp->pcr[3],
                       pp->pic[0], pp->pic[1], pp->pic[2], pp->pic[3]);
+
+               touch_nmi_watchdog();
        }
 
        memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));