mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 11:19:37 +00:00
![Marco Elver](/assets/img/avatar_default.png)
We must avoid any recursion into lockdep if KCSAN is enabled on utilities used by lockdep. One manifestation of this is corruption of lockdep's IRQ trace state (if TRACE_IRQFLAGS), resulting in spurious warnings (see below). This commit fixes this by: 1. Using raw_local_irq{save,restore} in kcsan_setup_watchpoint(). 2. Disabling lockdep in kcsan_report(). Tested with: CONFIG_LOCKDEP=y CONFIG_DEBUG_LOCKDEP=y CONFIG_TRACE_IRQFLAGS=y This fix eliminates spurious warnings such as the following one: WARNING: CPU: 0 PID: 2 at kernel/locking/lockdep.c:4406 check_flags.part.0+0x101/0x220 Modules linked in: CPU: 0 PID: 2 Comm: kthreadd Not tainted 5.5.0-rc1+ #11 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 RIP: 0010:check_flags.part.0+0x101/0x220 <snip> Call Trace: lock_is_held_type+0x69/0x150 freezer_fork+0x20b/0x370 cgroup_post_fork+0x2c9/0x5c0 copy_process+0x2675/0x3b40 _do_fork+0xbe/0xa30 ? _raw_spin_unlock_irqrestore+0x40/0x50 ? match_held_lock+0x56/0x250 ? kthread_park+0xf0/0xf0 kernel_thread+0xa6/0xd0 ? kthread_park+0xf0/0xf0 kthreadd+0x321/0x3d0 ? kthread_create_on_cpu+0x130/0x130 ret_from_fork+0x3a/0x50 irq event stamp: 64 hardirqs last enabled at (63): [<ffffffff9a7995d0>] _raw_spin_unlock_irqrestore+0x40/0x50 hardirqs last disabled at (64): [<ffffffff992a96d2>] kcsan_setup_watchpoint+0x92/0x460 softirqs last enabled at (32): [<ffffffff990489b8>] fpu__copy+0xe8/0x470 softirqs last disabled at (30): [<ffffffff99048939>] fpu__copy+0x69/0x470 Reported-by: Qian Cai <cai@lca.pw> Signed-off-by: Marco Elver <elver@google.com> Acked-by: Alexander Potapenko <glider@google.com> Tested-by: Qian Cai <cai@lca.pw> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
34 lines
1.2 KiB
Makefile
34 lines
1.2 KiB
Makefile
# SPDX-License-Identifier: GPL-2.0
|
|
# Any varying coverage in these files is non-deterministic
|
|
# and is generally not a function of system call inputs.
|
|
KCOV_INSTRUMENT := n
|
|
|
|
obj-y += mutex.o semaphore.o rwsem.o percpu-rwsem.o
|
|
|
|
# Avoid recursion lockdep -> KCSAN -> ... -> lockdep.
|
|
KCSAN_SANITIZE_lockdep.o := n
|
|
|
|
ifdef CONFIG_FUNCTION_TRACER
|
|
CFLAGS_REMOVE_lockdep.o = $(CC_FLAGS_FTRACE)
|
|
CFLAGS_REMOVE_lockdep_proc.o = $(CC_FLAGS_FTRACE)
|
|
CFLAGS_REMOVE_mutex-debug.o = $(CC_FLAGS_FTRACE)
|
|
CFLAGS_REMOVE_rtmutex-debug.o = $(CC_FLAGS_FTRACE)
|
|
endif
|
|
|
|
obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o
|
|
obj-$(CONFIG_LOCKDEP) += lockdep.o
|
|
ifeq ($(CONFIG_PROC_FS),y)
|
|
obj-$(CONFIG_LOCKDEP) += lockdep_proc.o
|
|
endif
|
|
obj-$(CONFIG_SMP) += spinlock.o
|
|
obj-$(CONFIG_LOCK_SPIN_ON_OWNER) += osq_lock.o
|
|
obj-$(CONFIG_PROVE_LOCKING) += spinlock.o
|
|
obj-$(CONFIG_QUEUED_SPINLOCKS) += qspinlock.o
|
|
obj-$(CONFIG_RT_MUTEXES) += rtmutex.o
|
|
obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o
|
|
obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o
|
|
obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock_debug.o
|
|
obj-$(CONFIG_QUEUED_RWLOCKS) += qrwlock.o
|
|
obj-$(CONFIG_LOCK_TORTURE_TEST) += locktorture.o
|
|
obj-$(CONFIG_WW_MUTEX_SELFTEST) += test-ww_mutex.o
|
|
obj-$(CONFIG_LOCK_EVENT_COUNTS) += lock_events.o
|