[GIT PULL] locking fixes
From: Ingo Molnar
Date: Sun Mar 25 2018 - 04:54:08 EST
Linus,
Please pull the latest locking-urgent-for-linus git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git locking-urgent-for-linus
# HEAD: 578ae447e7e5d78c90ac40a06406c1741f79ba96 jump_label: Disable jump labels in __exit code
Two fixes: tighten up a jump-labels warning to not trigger on certain modules and
fix confusing (and non-existent) mutex API documentation.
Thanks,
Ingo
------------------>
Josh Poimboeuf (1):
jump_label: Disable jump labels in __exit code
Matthew Wilcox (1):
locking/mutex: Improve documentation
include/linux/jump_label.h | 4 ++--
init/main.c | 2 +-
kernel/jump_label.c | 7 ++++---
kernel/locking/mutex.c | 37 ++++++++++++++++++++++++++++++-------
4 files changed, 37 insertions(+), 13 deletions(-)
diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h
index 2168cc6b8b30..b46b541c67c4 100644
--- a/include/linux/jump_label.h
+++ b/include/linux/jump_label.h
@@ -151,7 +151,7 @@ extern struct jump_entry __start___jump_table[];
extern struct jump_entry __stop___jump_table[];
extern void jump_label_init(void);
-extern void jump_label_invalidate_init(void);
+extern void jump_label_invalidate_initmem(void);
extern void jump_label_lock(void);
extern void jump_label_unlock(void);
extern void arch_jump_label_transform(struct jump_entry *entry,
@@ -199,7 +199,7 @@ static __always_inline void jump_label_init(void)
static_key_initialized = true;
}
-static inline void jump_label_invalidate_init(void) {}
+static inline void jump_label_invalidate_initmem(void) {}
static __always_inline bool static_key_false(struct static_key *key)
{
diff --git a/init/main.c b/init/main.c
index 969eaf140ef0..21efbf6ace93 100644
--- a/init/main.c
+++ b/init/main.c
@@ -1001,7 +1001,7 @@ static int __ref kernel_init(void *unused)
/* need to finish all async __init code before freeing the memory */
async_synchronize_full();
ftrace_free_init_mem();
- jump_label_invalidate_init();
+ jump_label_invalidate_initmem();
free_initmem();
mark_readonly();
system_state = SYSTEM_RUNNING;
diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index e7214093dcd1..01ebdf1f9f40 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -16,6 +16,7 @@
#include <linux/jump_label_ratelimit.h>
#include <linux/bug.h>
#include <linux/cpu.h>
+#include <asm/sections.h>
#ifdef HAVE_JUMP_LABEL
@@ -421,15 +422,15 @@ void __init jump_label_init(void)
cpus_read_unlock();
}
-/* Disable any jump label entries in __init code */
-void __init jump_label_invalidate_init(void)
+/* Disable any jump label entries in __init/__exit code */
+void __init jump_label_invalidate_initmem(void)
{
struct jump_entry *iter_start = __start___jump_table;
struct jump_entry *iter_stop = __stop___jump_table;
struct jump_entry *iter;
for (iter = iter_start; iter < iter_stop; iter++) {
- if (init_kernel_text(iter->code))
+ if (init_section_contains((void *)(unsigned long)iter->code, 1))
iter->code = 0;
}
}
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index 858a07590e39..2048359f33d2 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -1082,15 +1082,16 @@ static noinline int __sched
__mutex_lock_interruptible_slowpath(struct mutex *lock);
/**
- * mutex_lock_interruptible - acquire the mutex, interruptible
- * @lock: the mutex to be acquired
+ * mutex_lock_interruptible() - Acquire the mutex, interruptible by signals.
+ * @lock: The mutex to be acquired.
*
- * Lock the mutex like mutex_lock(), and return 0 if the mutex has
- * been acquired or sleep until the mutex becomes available. If a
- * signal arrives while waiting for the lock then this function
- * returns -EINTR.
+ * Lock the mutex like mutex_lock(). If a signal is delivered while the
+ * process is sleeping, this function will return without acquiring the
+ * mutex.
*
- * This function is similar to (but not equivalent to) down_interruptible().
+ * Context: Process context.
+ * Return: 0 if the lock was successfully acquired or %-EINTR if a
+ * signal arrived.
*/
int __sched mutex_lock_interruptible(struct mutex *lock)
{
@@ -1104,6 +1105,18 @@ int __sched mutex_lock_interruptible(struct mutex *lock)
EXPORT_SYMBOL(mutex_lock_interruptible);
+/**
+ * mutex_lock_killable() - Acquire the mutex, interruptible by fatal signals.
+ * @lock: The mutex to be acquired.
+ *
+ * Lock the mutex like mutex_lock(). If a signal which will be fatal to
+ * the current process is delivered while the process is sleeping, this
+ * function will return without acquiring the mutex.
+ *
+ * Context: Process context.
+ * Return: 0 if the lock was successfully acquired or %-EINTR if a
+ * fatal signal arrived.
+ */
int __sched mutex_lock_killable(struct mutex *lock)
{
might_sleep();
@@ -1115,6 +1128,16 @@ int __sched mutex_lock_killable(struct mutex *lock)
}
EXPORT_SYMBOL(mutex_lock_killable);
+/**
+ * mutex_lock_io() - Acquire the mutex and mark the process as waiting for I/O
+ * @lock: The mutex to be acquired.
+ *
+ * Lock the mutex like mutex_lock(). While the task is waiting for this
+ * mutex, it will be accounted as being in the IO wait state by the
+ * scheduler.
+ *
+ * Context: Process context.
+ */
void __sched mutex_lock_io(struct mutex *lock)
{
int token;