Commit e59a175f authored by Nathan Lynch's avatar Nathan Lynch Committed by Michael Ellerman
Browse files

powerpc/pseries/mobility: prevent cpu hotplug during DT update 



CPU online/offline code paths are sensitive to parts of the device
tree (various cpu node properties, cache nodes) that can be changed as
a result of a migration.

Prevent CPU hotplug while the device tree potentially is inconsistent.

Fixes: 410bccf9 ("powerpc/pseries: Partition migration in the kernel")
Signed-off-by: default avatarNathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: default avatarGautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent d4aa219a

arch/powerpc/platforms/pseries/mobility.c

+9 −0
Original line number Diff line number Diff line
@@ -9,6 +9,7 @@ 
 * 2 as published by the Free Software Foundation.

 */



#include <linux/cpu.h>

#include <linux/kernel.h>

#include <linux/kobject.h>

#include <linux/smp.h>
@@ -338,11 +339,19 @@ void post_mobility_fixup(void) 
	if (rc)

		printk(KERN_ERR "Post-mobility activate-fw failed: %d\n", rc);



	/*

	 * We don't want CPUs to go online/offline while the device

	 * tree is being updated.

	 */

	cpus_read_lock();



	rc = pseries_devicetree_update(MIGRATION_SCOPE);

	if (rc)

		printk(KERN_ERR "Post-mobility device tree update "

			"failed: %d\n", rc);



	cpus_read_unlock();



	/* Possibly switch to a new RFI flush type */

	pseries_setup_rfi_flush();