[PATCH] fadump: allow duplicate assignment to /sys/kernel/fadump_registered when it's assigned the desired value already

[Wang Sheng-Hui]

When the fadump is enabled, we have /sys/kernel/fadump_enabled assigned 1.
But sometimes we need to restart the fadump service by 'service kdump restart',
in case the kdump script has added the fadump detect/support already.
In current implementation, we cannot re-assign 1 to /sys/kernel/fadump_enabled
if 1 is already set and we have added more logic check in the user space script.

I think we can enable the duplicate assignment to ease the user space tools,
as long as the value is the right 1 or 0.

Signed-off-by: Wang Sheng-Hui <shhuiw at gmail.com>
---
  arch/powerpc/kernel/fadump.c |    8 ++------
  1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
index 06c8202..e1347e5 100644
--- a/arch/powerpc/kernel/fadump.c
+++ b/arch/powerpc/kernel/fadump.c
@@ -1140,18 +1140,14 @@ static ssize_t fadump_register_store(struct kobject *kobj,

  	switch (buf[0]) {
  	case '0':
-		if (fw_dump.dump_registered == 0) {
-			ret = -EINVAL;
+		if (fw_dump.dump_registered == 0)
  			goto unlock_out;
-		}
  		/* Un-register Firmware-assisted dump */
  		fadump_unregister_dump(&fdm);
  		break;
  	case '1':
-		if (fw_dump.dump_registered == 1) {
-			ret = -EINVAL;
+		if (fw_dump.dump_registered == 1)
  			goto unlock_out;
-		}
  		/* Register Firmware-assisted dump */
  		register_fadump();
  		break;
-- 
1.7.10.4