[PATCH 1/2] lockdep: allow instrumenting lockdep.c with KMSAN
From: Alexander Potapenko
Date: Mon Nov 28 2022 - 04:46:00 EST
Lockdep and KMSAN used to play badly together, causing deadlocks when
KMSAN instrumentation of lockdep.c called lockdep functions recursively.
Looks like this is no more the case, and a kernel can run (yet slower)
with both KMSAN and lockdep enabled.
This patch should fix false positives on wq_head->lock->dep_map, which
KMSAN used to consider uninitialized because of lockdep.c not being
instrumented.
Link: https://lore.kernel.org/lkml/Y3b9AAEKp2Vr3e6O@sol.localdomain/
Reported-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx>
---
kernel/locking/Makefile | 1 -
1 file changed, 1 deletion(-)
diff --git a/kernel/locking/Makefile b/kernel/locking/Makefile
index ea925731fa40f..0db4093d17b8a 100644
--- a/kernel/locking/Makefile
+++ b/kernel/locking/Makefile
@@ -7,7 +7,6 @@ obj-y += mutex.o semaphore.o rwsem.o percpu-rwsem.o
# Avoid recursion lockdep -> sanitizer -> ... -> lockdep.
KCSAN_SANITIZE_lockdep.o := n
-KMSAN_SANITIZE_lockdep.o := n
ifdef CONFIG_FUNCTION_TRACER
CFLAGS_REMOVE_lockdep.o = $(CC_FLAGS_FTRACE)
--
2.38.1.584.g0f3c55d4c2-goog