[PATCH 07/11] xen/sys-hypervisor: Add release callback to hyp_sysfs_kobj_type

From: Ian Rogers <irogers@google.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	"Rafael J . Wysocki" <rafael@kernel.org>,
	 Danilo Krummrich <dakr@kernel.org>,
	Miguel Ojeda <ojeda@kernel.org>, Kees Cook <kees@kernel.org>,
	 Nathan Chancellor <nathan@kernel.org>
Cc: "Nick Desaulniers" <ndesaulniers@google.com>,
	"Bill Wendling" <morbo@google.com>,
	"Justin Stitt" <justinstitt@google.com>,
	"Jonathan Corbet" <corbet@lwn.net>,
	"Madhavan Srinivasan" <maddy@linux.ibm.com>,
	"Michael Ellerman" <mpe@ellerman.id.au>,
	"Nicholas Piggin" <npiggin@gmail.com>,
	"Christophe Leroy" <chleroy@kernel.org>,
	"Nayna Jain" <nayna@linux.ibm.com>,
	"Yoshinori Sato" <ysato@users.sourceforge.jp>,
	"Rich Felker" <dalias@libc.org>,
	"John Paul Adrian Glaubitz" <glaubitz@physik.fu-berlin.de>,
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	"Zhihao Cheng" <chengzhihao1@huawei.com>,
	"Felix Kuehling" <Felix.Kuehling@amd.com>,
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	"Christian König" <christian.koenig@amd.com>,
	driver-core@lists.linux.dev, llvm@lists.linux.dev,
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	linux-kernel@vger.kernel.org, "Ian Rogers" <irogers@google.com>
Subject: [PATCH 07/11] xen/sys-hypervisor: Add release callback to hyp_sysfs_kobj_type
Date: Tue, 13 Oct 2026 15:39:42 -0700	[thread overview]
Message-ID: <20261013223946.1836757-8-irogers@google.com> (raw)
In-Reply-To: <20261013223946.1836757-1-irogers@google.com>

hypervisor_init() in drivers/base/hypervisor.c creates hypervisor_kobj
with kobject_create_and_add() (which allocates a dynamic kobject using
dynamic_kobj_ktype), and hypervisor_subsys_init() in
drivers/xen/sys-hypervisor.c then overwrites hypervisor_kobj->ktype with
&hyp_sysfs_kobj_type, which had no .release callback.

Add hyp_sysfs_release() calling kfree(kobj) to preserve the dynamic
kobject release behavior.

Fixes: cff7e81b3dd7 ("xen: add /sys/hypervisor support")
Assisted-by: Antigravity:gemini-3.1-pro
Signed-off-by: Ian Rogers <irogers@google.com>
---
 drivers/xen/sys-hypervisor.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/xen/sys-hypervisor.c b/drivers/xen/sys-hypervisor.c
index 91923242a5ae..0e8a2cd69fd6 100644
--- a/drivers/xen/sys-hypervisor.c
+++ b/drivers/xen/sys-hypervisor.c
@@ -659,7 +659,13 @@ static const struct sysfs_ops hyp_sysfs_ops = {
 	.store = hyp_sysfs_store,
 };
 
+static void hyp_sysfs_release(struct kobject *kobj)
+{
+	kfree(kobj);
+}
+
 static const struct kobj_type hyp_sysfs_kobj_type = {
+	.release = hyp_sysfs_release,
 	.sysfs_ops = &hyp_sysfs_ops,
 };
 
-- 
2.56.0.385.gd3acb90ef8-goog

