Commit a7c561f2 authored by Thomas Klein's avatar Thomas Klein Committed by David S. Miller
Browse files

ehea: fix possible DLPAR/mem deadlock 



Force serialization of userspace-triggered DLPAR/mem operations

Signed-off-by: default avatarThomas Klein <tklein@de.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent ea96ceac

drivers/net/ehea/ehea.h

+1 −1
Original line number Diff line number Diff line
@@ -40,7 +40,7 @@ 
#include <asm/io.h>



#define DRV_NAME	"ehea"

#define DRV_VERSION	"EHEA_0102"

#define DRV_VERSION	"EHEA_0103"



/* eHEA capability flags */

#define DLPAR_PORT_ADD_REM 1

drivers/net/ehea/ehea_main.c

+14 −5
Original line number Diff line number Diff line
@@ -2889,7 +2889,6 @@ static void ehea_rereg_mrs(struct work_struct *work) 
	int ret, i;

	struct ehea_adapter *adapter;



	mutex_lock(&dlpar_mem_lock);

	ehea_info("LPAR memory changed - re-initializing driver");



	list_for_each_entry(adapter, &adapter_list, list)
@@ -2959,7 +2958,6 @@ static void ehea_rereg_mrs(struct work_struct *work) 
		}

	ehea_info("re-initializing driver complete");

out:

	mutex_unlock(&dlpar_mem_lock);

	return;

}
@@ -3542,7 +3540,14 @@ void ehea_crash_handler(void) 
static int ehea_mem_notifier(struct notifier_block *nb,

                             unsigned long action, void *data)

{

	int ret = NOTIFY_BAD;

	struct memory_notify *arg = data;



	if (!mutex_trylock(&dlpar_mem_lock)) {

		ehea_info("ehea_mem_notifier must not be called parallelized");

		goto out;

	}



	switch (action) {

	case MEM_CANCEL_OFFLINE:

		ehea_info("memory offlining canceled");
@@ -3551,14 +3556,14 @@ static int ehea_mem_notifier(struct notifier_block *nb, 
		ehea_info("memory is going online");

		set_bit(__EHEA_STOP_XFER, &ehea_driver_flags);

		if (ehea_add_sect_bmap(arg->start_pfn, arg->nr_pages))

			return NOTIFY_BAD;

			goto out_unlock;

		ehea_rereg_mrs(NULL);

		break;

	case MEM_GOING_OFFLINE:

		ehea_info("memory is going offline");

		set_bit(__EHEA_STOP_XFER, &ehea_driver_flags);

		if (ehea_rem_sect_bmap(arg->start_pfn, arg->nr_pages))

			return NOTIFY_BAD;

			goto out_unlock;

		ehea_rereg_mrs(NULL);

		break;

	default:
@@ -3566,8 +3571,12 @@ static int ehea_mem_notifier(struct notifier_block *nb, 
	}



	ehea_update_firmware_handles();

	ret = NOTIFY_OK;



	return NOTIFY_OK;

out_unlock:

	mutex_unlock(&dlpar_mem_lock);

out:

	return ret;

}



static struct notifier_block ehea_mem_nb = {