[RFC v2 10/10] pseries/papr-hvpipe: Fix error handling in case of init routine fails

[Ritesh Harjani (IBM)]

We have already enabled interrupt sources and enabled hvpipe to received
interrupts, if misc_register() fails, we will destroy the workqueue, but
the HMC might send us a msg via hvpipe which will call, queue work on
the workqueue which might be destroyed.

So instead, let's reverse the order of enabling set_hvpipe_sys_param(1)
and in case of an error let's remove the misc dev by calling
misc_deregister().

Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx>
---
 arch/powerpc/platforms/pseries/papr-hvpipe.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/papr-hvpipe.c b/arch/powerpc/platforms/pseries/papr-hvpipe.c
index c708869ca732..b6d0b36915c6 100644
--- a/arch/powerpc/platforms/pseries/papr-hvpipe.c
+++ b/arch/powerpc/platforms/pseries/papr-hvpipe.c
@@ -785,18 +785,20 @@ static int __init papr_hvpipe_init(void)
 	if (ret)
 		goto out_wq;

-	ret = set_hvpipe_sys_param(1);
+	ret = misc_register(&papr_hvpipe_dev);
 	if (ret)
 		goto out_wq;

-	ret = misc_register(&papr_hvpipe_dev);
+	ret = set_hvpipe_sys_param(1);
 	if (ret)
-		goto out_wq;
+		goto out_misc;

 	pr_info("hvpipe feature is enabled\n");
 	hvpipe_feature = true;
 	return 0;

+out_misc:
+	misc_deregister(&papr_hvpipe_dev);
 out_wq:
 	destroy_workqueue(papr_hvpipe_wq);
 out:
--
2.39.5