[PATCH 2/2] powerpc/mobility: disabling hard lockup watchdog during LPM

From: Laurent Dufour
Date: Wed Jun 01 2022 - 11:53:46 EST


Disabling the Hard Lockup Watchdog until the memory transfer is complete.

This avoids hard lockup seen while the memory is still in progress when the
system is heavily loaded and a lot of pages are still not transferred on
the arrival side.

Signed-off-by: Laurent Dufour <ldufour@xxxxxxxxxxxxx>
---
arch/powerpc/platforms/pseries/mobility.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/arch/powerpc/platforms/pseries/mobility.c b/arch/powerpc/platforms/pseries/mobility.c
index 55612a1b07d6..061d4faefefb 100644
--- a/arch/powerpc/platforms/pseries/mobility.c
+++ b/arch/powerpc/platforms/pseries/mobility.c
@@ -701,6 +701,9 @@ static int pseries_migrate_partition(u64 handle)

vas_migration_handler(VAS_SUSPEND);

+ pr_debug("Disabling the NMI watchdog\n");
+ watchdog_nmi_stop();
+
ret = pseries_suspend(handle);
if (ret == 0) {
post_mobility_fixup();
@@ -708,6 +711,9 @@ static int pseries_migrate_partition(u64 handle)
} else
pseries_cancel_migration(handle, ret);

+ pr_debug("Enabling the NMI watchdog again\n");
+ watchdog_nmi_start();
+
vas_migration_handler(VAS_RESUME);

return ret;
--
2.36.1