linux-kernel - [PATCH] module: Remove duplicate freeing of lockdep classes

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Message-ID: <20260107122329.1324707-1-petr.pavlu@suse.com>
Date: Wed,  7 Jan 2026 13:22:57 +0100
From: Petr Pavlu <petr.pavlu@...e.com>
To: Luis Chamberlain <mcgrof@...nel.org>,
	Petr Pavlu <petr.pavlu@...e.com>,
	Daniel Gomez <da.gomez@...nel.org>,
	Sami Tolvanen <samitolvanen@...gle.com>
Cc: Aaron Tomlin <atomlin@...mlin.com>,
	Peter Zijlstra <peterz@...radead.org>,
	Ingo Molnar <mingo@...hat.com>,
	Will Deacon <will@...nel.org>,
	Boqun Feng <boqun.feng@...il.com>,
	Waiman Long <longman@...hat.com>,
	Song Liu <song@...nel.org>,
	linux-modules@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH] module: Remove duplicate freeing of lockdep classes

In the error path of load_module(), under the free_module label, the
code calls lockdep_free_key_range() to release lock classes associated
with the MOD_DATA, MOD_RODATA and MOD_RO_AFTER_INIT module regions, and
subsequently invokes module_deallocate().

Since commit ac3b43283923 ("module: replace module_layout with
module_memory"), the module_deallocate() function calls free_mod_mem(),
which releases the lock classes as well and considers all module
regions.

Attempting to free these classes twice is unnecessary. Remove the
redundant code in load_module().

Signed-off-by: Petr Pavlu <petr.pavlu@...e.com>
---
 kernel/module/main.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/kernel/module/main.c b/kernel/module/main.c
index 710ee30b3bea..bcd259505c8b 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -3544,12 +3544,6 @@ static int load_module(struct load_info *info, const char __user *uargs,
 	mutex_unlock(&module_mutex);
  free_module:
 	mod_stat_bump_invalid(info, flags);
-	/* Free lock-classes; relies on the preceding sync_rcu() */
-	for_class_mod_mem_type(type, core_data) {
-		lockdep_free_key_range(mod->mem[type].base,
-				       mod->mem[type].size);
-	}
-
 	module_memory_restore_rox(mod);
 	module_deallocate(mod, info);
  free_copy:

base-commit: 3609fa95fb0f2c1b099e69e56634edb8fc03f87c
-- 
2.52.0