From f653ff7af96951faa69c68665d44bed80702544f Mon Sep 17 00:00:00 2001
From: Pasha Tatashin <pasha.tatashin@soleen.com>
Date: Thu, 18 Dec 2025 10:57:52 -0500
Subject: tests/liveupdate: add in-kernel liveupdate test

Introduce an in-kernel test module to validate the core logic of the Live
Update Orchestrator's File-Lifecycle-Bound feature.  This provides a
low-level, controlled environment to test FLB registration and callback
invocation without requiring userspace interaction or actual kexec
reboots.

The test is enabled by the CONFIG_LIVEUPDATE_TEST Kconfig option.

Link: https://lkml.kernel.org/r/20251218155752.3045808-6-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Alexander Graf <graf@amazon.com>
Cc: David Gow <davidgow@google.com>
Cc: David Matlack <dmatlack@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <kees@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Pratyush Yadav <pratyush@kernel.org>
Cc: Samiullah Khawaja <skhawaja@google.com>
Cc: Tamir Duberstein <tamird@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 kernel/liveupdate/luo_file.c     | 8 +++++++-
 kernel/liveupdate/luo_internal.h | 8 ++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

(limited to 'kernel')

diff --git a/kernel/liveupdate/luo_file.c b/kernel/liveupdate/luo_file.c
index cade273c50c9..35d2a8b1a0df 100644
--- a/kernel/liveupdate/luo_file.c
+++ b/kernel/liveupdate/luo_file.c
@@ -864,6 +864,8 @@ int liveupdate_register_file_handler(struct liveupdate_file_handler *fh)
 	list_add_tail(&ACCESS_PRIVATE(fh, list), &luo_file_handler_list);
 	luo_session_resume();
 
+	liveupdate_test_register(fh);
+
 	return 0;
 
 err_resume:
@@ -895,8 +897,10 @@ int liveupdate_unregister_file_handler(struct liveupdate_file_handler *fh)
 	if (!liveupdate_enabled())
 		return -EOPNOTSUPP;
 
+	liveupdate_test_unregister(fh);
+
 	if (!luo_session_quiesce())
-		return -EBUSY;
+		goto err_register;
 
 	if (!list_empty(&ACCESS_PRIVATE(fh, flb_list)))
 		goto err_resume;
@@ -909,5 +913,7 @@ int liveupdate_unregister_file_handler(struct liveupdate_file_handler *fh)
 
 err_resume:
 	luo_session_resume();
+err_register:
+	liveupdate_test_register(fh);
 	return err;
 }
diff --git a/kernel/liveupdate/luo_internal.h b/kernel/liveupdate/luo_internal.h
index 99db13d99530..8083d8739b09 100644
--- a/kernel/liveupdate/luo_internal.h
+++ b/kernel/liveupdate/luo_internal.h
@@ -107,4 +107,12 @@ int __init luo_flb_setup_outgoing(void *fdt);
 int __init luo_flb_setup_incoming(void *fdt);
 void luo_flb_serialize(void);
 
+#ifdef CONFIG_LIVEUPDATE_TEST
+void liveupdate_test_register(struct liveupdate_file_handler *fh);
+void liveupdate_test_unregister(struct liveupdate_file_handler *fh);
+#else
+static inline void liveupdate_test_register(struct liveupdate_file_handler *fh) { }
+static inline void liveupdate_test_unregister(struct liveupdate_file_handler *fh) { }
+#endif
+
 #endif /* _LINUX_LUO_INTERNAL_H */
-- 
cgit v1.2.3