diff mbox series

powerpc/numa: Handle unitialized timer reset

Message ID c6639718-a8a5-7595-aa96-4a0395092adc@linux.vnet.ibm.com (mailing list archive)
State Superseded
Headers show
Series powerpc/numa: Handle unitialized timer reset | expand

Commit Message

Michael Bringmann April 24, 2018, 10 p.m. UTC 
Some of the code in 'numa.c' may be reused when updating kernel
state after an LPAR migration event.  One such common function
is 'reset_topology_timer' which was being invoked by the
'.notifier_call' function within the NUMA module by
'of_property_notify'.  If this occurs after a previous call to
'stop_topology_update' or on a system without VPHN enabled, the
code runs into an unitialized timer structure and crashes.  This
patch adds a safety check along this path toward the problem code.

Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
---
 arch/powerpc/mm/numa.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 57a5029..8802e7d 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -1457,7 +1457,8 @@  static void topology_timer_fn(struct timer_list *unused)
 
 static void reset_topology_timer(void)
 {
-	mod_timer(&topology_timer, jiffies + topology_timer_secs * HZ);
+	if (vphn_enabled)
+		mod_timer(&topology_timer, jiffies + topology_timer_secs * HZ);
 }
 
 #ifdef CONFIG_SMP