Do not update sysfs cpu registration from invalid context

PATCH New Nathan Fontenot 1 participant 1 message Jun 25, 2013 PowerPC

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Nathan Fontenot

author

2013-06-25 03:08 UTC #0 lore raw

PATCH v2 1/1 Do not update sysfs cpu registration from invalid context

The topology update code that updates the cpu node registration in sysfs should not be called while in stop_machine(). The register/unregister calls take a lock and may sleep.

This patch moves these calls outside of the call to stop_machine().

Signed-off-by Nathan Fontenot <[email protected]>

---
 arch/powerpc/mm/numa.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

arch/powerpc/mm/numa.c +3 -2

Index: powerpc/arch/powerpc/mm/numa.c
===================================================================
@@ -1433,11 +1433,9 @@
 		if (cpu != update->cpu)
 			continue;
 
-		unregister_cpu_under_node(update->cpu, update->old_nid);
 		unmap_cpu_from_node(update->cpu);
 		map_cpu_to_node(update->cpu, update->new_nid);
 		vdso_getcpu_init();
-		register_cpu_under_node(update->cpu, update->new_nid);
 	}
 
 	return 0;

@@ -1485,6 +1483,9 @@
 	stop_machine(update_cpu_topology, &updates[0], &updated_cpus);
 
 	for (ud = &updates[0]; ud; ud = ud->next) {
+		unregister_cpu_under_node(ud->cpu, ud->old_nid);
+		register_cpu_under_node(ud->cpu, ud->new_nid);
+
 		dev = get_cpu_device(ud->cpu);
 		if (dev)
 			kobject_uevent(&dev->kobj, KOBJ_CHANGE);