From 1e8e4a7cc2fa3017b1daf02612e095d51924ce1e Mon Sep 17 00:00:00 2001 From: Alexander Potapenko Date: Mon, 28 Nov 2022 10:45:40 +0100 Subject: [PATCH] lockdep: allow instrumenting lockdep.c with KMSAN 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/ Link: https://lkml.kernel.org/r/20221128094541.2645890-1-glider@google.com Signed-off-by: Alexander Potapenko Reported-by: Eric Biggers Cc: Dmitry Vyukov Cc: Ingo Molnar Cc: Marco Elver Cc: Peter Zijlstra Cc: Will Deacon Signed-off-by: Andrew Morton --- kernel/locking/Makefile | 1 - 1 file changed, 1 deletion(-) diff --git a/kernel/locking/Makefile b/kernel/locking/Makefile index ea925731fa40..0db4093d17b8 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)