This is a note to let you know that I've just added the patch titled
powerpc: fix unbalanced node refcount in check_kvm_guest()
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
powerpc-fix-unbalanced-node-refcount-in-check_kvm_gu.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit d47984e0564f2979a5adedd79199472513ad0268
Author: Nathan Lynch <nathanl@xxxxxxxxxxxxx>
Date: Tue Sep 28 07:45:50 2021 -0500
powerpc: fix unbalanced node refcount in check_kvm_guest()
[ Upstream commit 56537faf8821e361d739fc5ff58c9c40f54a1d4c ]
When check_kvm_guest() succeeds in looking up a /hypervisor OF node, it
returns without performing a matching put for the lookup, leaving the
node's reference count elevated.
Add the necessary call to of_node_put(), rearranging the code slightly to
avoid repetition or goto.
Fixes: 107c55005fbd ("powerpc/pseries: Add KVM guest doorbell restrictions")
Signed-off-by: Nathan Lynch <nathanl@xxxxxxxxxxxxx>
Reviewed-by: Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Tyrel Datwyler <tyreld@xxxxxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20210928124550.132020-1-nathanl@xxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/powerpc/kernel/firmware.c b/arch/powerpc/kernel/firmware.c
index c7022c41cc314..20328f72f9f2b 100644
--- a/arch/powerpc/kernel/firmware.c
+++ b/arch/powerpc/kernel/firmware.c
@@ -31,11 +31,10 @@ int __init check_kvm_guest(void)
if (!hyper_node)
return 0;
- if (!of_device_is_compatible(hyper_node, "linux,kvm"))
- return 0;
-
- static_branch_enable(&kvm_guest);
+ if (of_device_is_compatible(hyper_node, "linux,kvm"))
+ static_branch_enable(&kvm_guest);
+ of_node_put(hyper_node);
return 0;
}
core_initcall(check_kvm_guest); // before kvm_guest_init()
