[PATCH 4.19 139/321] KVM: s390: unregister debug feature on failing arch init

Greg Kroah-Hartman
2019-12-03T22:51:09Z

From: Michael Mueller <mimu@linux.ibm.com>

[ Upstream commit 308c3e6673b012beecb96ef04cc65f4a0e7cdd99 ]

Make sure the debug feature and its allocated resources get
released upon unsuccessful architecture initialization.

A related indication of the issue will be reported as kernel
message.

Signed-off-by: Michael Mueller <mimu@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181130143215.69496-2-mimu@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/s390/kvm/kvm-s390.c | 17 ++++++++++++++---
1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 3c317bc6b7997..db3196aebaa1c 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -416,19 +416,30 @@ static void kvm_s390_cpu_feat_init(void)

int kvm_arch_init(void *opaque)
{
+ int rc;
+
kvm_s390_dbf = debug_register("kvm-trace", 32, 1, 7 * sizeof(long));
if (!kvm_s390_dbf)
return -ENOMEM;

if (debug_register_view(kvm_s390_dbf, &debug_sprintf_view)) {
- debug_unregister(kvm_s390_dbf);
- return -ENOMEM;
+ rc = -ENOMEM;
+ goto out_debug_unreg;
}

kvm_s390_cpu_feat_init();

/* Register floating interrupt controller interface. */
- return kvm_register_device_ops(&kvm_flic_ops, KVM_DEV_TYPE_FLIC);
+ rc = kvm_register_device_ops(&kvm_flic_ops, KVM_DEV_TYPE_FLIC);
+ if (rc) {
+ pr_err("Failed to register FLIC rc=%d\n", rc);
+ goto out_debug_unreg;
+ }
+ return 0;
+
+out_debug_unreg:
+ debug_unregister(kvm_s390_dbf);
+ return rc;
}

void kvm_arch_exit(void)
--
2.20.1