From: Ingo Molnar <mingo@kernel.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org,
Peter Zijlstra <a.p.zijlstra@chello.nl>,
Thomas Gleixner <tglx@linutronix.de>,
Will Deacon <will@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>
Subject: [GIT PULL] locking fixes
Date: Sun, 21 Mar 2021 11:53:43 +0100 [thread overview]
Message-ID: <20210321105343.GA124289@gmail.com> (raw)
Linus,
Please pull the latest locking/urgent git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git locking-urgent-2021-03-21
# HEAD: 38c93587375053c5b9ef093f4a5ea754538cba32 static_call: Fix static_call_update() sanity check
Locking fixes:
- Get static calls & modules right. Hopefully.
- WW mutex fixes
Thanks,
Ingo
------------------>
Peter Zijlstra (3):
static_call: Fix static_call_set_init()
static_call: Align static_call_is_init() patching condition
static_call: Fix static_call_update() sanity check
Waiman Long (2):
locking/ww_mutex: Simplify use_ww_ctx & ww_ctx handling
locking/ww_mutex: Fix acquire/release imbalance in ww_acquire_init()/ww_acquire_fini()
include/linux/ww_mutex.h | 5 +++--
kernel/jump_label.c | 8 ++++++++
kernel/locking/mutex.c | 25 ++++++++++++++-----------
kernel/static_call.c | 42 ++++++++++++++++++++++++------------------
4 files changed, 49 insertions(+), 31 deletions(-)
diff --git a/include/linux/ww_mutex.h b/include/linux/ww_mutex.h
index 850424e5d030..6ecf2a0220db 100644
--- a/include/linux/ww_mutex.h
+++ b/include/linux/ww_mutex.h
@@ -173,9 +173,10 @@ static inline void ww_acquire_done(struct ww_acquire_ctx *ctx)
*/
static inline void ww_acquire_fini(struct ww_acquire_ctx *ctx)
{
-#ifdef CONFIG_DEBUG_MUTEXES
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
mutex_release(&ctx->dep_map, _THIS_IP_);
-
+#endif
+#ifdef CONFIG_DEBUG_MUTEXES
DEBUG_LOCKS_WARN_ON(ctx->acquired);
if (!IS_ENABLED(CONFIG_PROVE_LOCKING))
/*
diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index c6a39d662935..ba39fbb1f8e7 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -407,6 +407,14 @@ static bool jump_label_can_update(struct jump_entry *entry, bool init)
return false;
if (!kernel_text_address(jump_entry_code(entry))) {
+ /*
+ * This skips patching built-in __exit, which
+ * is part of init_section_contains() but is
+ * not part of kernel_text_address().
+ *
+ * Skipping built-in __exit is fine since it
+ * will never be executed.
+ */
WARN_ONCE(!jump_entry_is_init(entry),
"can't patch jump_label at %pS",
(void *)jump_entry_code(entry));
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index adb935090768..622ebdfcd083 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -626,7 +626,7 @@ static inline int mutex_can_spin_on_owner(struct mutex *lock)
*/
static __always_inline bool
mutex_optimistic_spin(struct mutex *lock, struct ww_acquire_ctx *ww_ctx,
- const bool use_ww_ctx, struct mutex_waiter *waiter)
+ struct mutex_waiter *waiter)
{
if (!waiter) {
/*
@@ -702,7 +702,7 @@ mutex_optimistic_spin(struct mutex *lock, struct ww_acquire_ctx *ww_ctx,
#else
static __always_inline bool
mutex_optimistic_spin(struct mutex *lock, struct ww_acquire_ctx *ww_ctx,
- const bool use_ww_ctx, struct mutex_waiter *waiter)
+ struct mutex_waiter *waiter)
{
return false;
}
@@ -922,6 +922,9 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
struct ww_mutex *ww;
int ret;
+ if (!use_ww_ctx)
+ ww_ctx = NULL;
+
might_sleep();
#ifdef CONFIG_DEBUG_MUTEXES
@@ -929,7 +932,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
#endif
ww = container_of(lock, struct ww_mutex, base);
- if (use_ww_ctx && ww_ctx) {
+ if (ww_ctx) {
if (unlikely(ww_ctx == READ_ONCE(ww->ctx)))
return -EALREADY;
@@ -946,10 +949,10 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
mutex_acquire_nest(&lock->dep_map, subclass, 0, nest_lock, ip);
if (__mutex_trylock(lock) ||
- mutex_optimistic_spin(lock, ww_ctx, use_ww_ctx, NULL)) {
+ mutex_optimistic_spin(lock, ww_ctx, NULL)) {
/* got the lock, yay! */
lock_acquired(&lock->dep_map, ip);
- if (use_ww_ctx && ww_ctx)
+ if (ww_ctx)
ww_mutex_set_context_fastpath(ww, ww_ctx);
preempt_enable();
return 0;
@@ -960,7 +963,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
* After waiting to acquire the wait_lock, try again.
*/
if (__mutex_trylock(lock)) {
- if (use_ww_ctx && ww_ctx)
+ if (ww_ctx)
__ww_mutex_check_waiters(lock, ww_ctx);
goto skip_wait;
@@ -1013,7 +1016,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
goto err;
}
- if (use_ww_ctx && ww_ctx) {
+ if (ww_ctx) {
ret = __ww_mutex_check_kill(lock, &waiter, ww_ctx);
if (ret)
goto err;
@@ -1026,7 +1029,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
* ww_mutex needs to always recheck its position since its waiter
* list is not FIFO ordered.
*/
- if ((use_ww_ctx && ww_ctx) || !first) {
+ if (ww_ctx || !first) {
first = __mutex_waiter_is_first(lock, &waiter);
if (first)
__mutex_set_flag(lock, MUTEX_FLAG_HANDOFF);
@@ -1039,7 +1042,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
* or we must see its unlock and acquire.
*/
if (__mutex_trylock(lock) ||
- (first && mutex_optimistic_spin(lock, ww_ctx, use_ww_ctx, &waiter)))
+ (first && mutex_optimistic_spin(lock, ww_ctx, &waiter)))
break;
spin_lock(&lock->wait_lock);
@@ -1048,7 +1051,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
acquired:
__set_current_state(TASK_RUNNING);
- if (use_ww_ctx && ww_ctx) {
+ if (ww_ctx) {
/*
* Wound-Wait; we stole the lock (!first_waiter), check the
* waiters as anyone might want to wound us.
@@ -1068,7 +1071,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
/* got the lock - cleanup and rejoice! */
lock_acquired(&lock->dep_map, ip);
- if (use_ww_ctx && ww_ctx)
+ if (ww_ctx)
ww_mutex_lock_acquired(ww, ww_ctx);
spin_unlock(&lock->wait_lock);
diff --git a/kernel/static_call.c b/kernel/static_call.c
index ae825295cf68..2c5950b0b90e 100644
--- a/kernel/static_call.c
+++ b/kernel/static_call.c
@@ -35,27 +35,30 @@ static inline void *static_call_addr(struct static_call_site *site)
return (void *)((long)site->addr + (long)&site->addr);
}
+static inline unsigned long __static_call_key(const struct static_call_site *site)
+{
+ return (long)site->key + (long)&site->key;
+}
static inline struct static_call_key *static_call_key(const struct static_call_site *site)
{
- return (struct static_call_key *)
- (((long)site->key + (long)&site->key) & ~STATIC_CALL_SITE_FLAGS);
+ return (void *)(__static_call_key(site) & ~STATIC_CALL_SITE_FLAGS);
}
/* These assume the key is word-aligned. */
static inline bool static_call_is_init(struct static_call_site *site)
{
- return ((long)site->key + (long)&site->key) & STATIC_CALL_SITE_INIT;
+ return __static_call_key(site) & STATIC_CALL_SITE_INIT;
}
static inline bool static_call_is_tail(struct static_call_site *site)
{
- return ((long)site->key + (long)&site->key) & STATIC_CALL_SITE_TAIL;
+ return __static_call_key(site) & STATIC_CALL_SITE_TAIL;
}
static inline void static_call_set_init(struct static_call_site *site)
{
- site->key = ((long)static_call_key(site) | STATIC_CALL_SITE_INIT) -
+ site->key = (__static_call_key(site) | STATIC_CALL_SITE_INIT) -
(long)&site->key;
}
@@ -146,6 +149,7 @@ void __static_call_update(struct static_call_key *key, void *tramp, void *func)
};
for (site_mod = &first; site_mod; site_mod = site_mod->next) {
+ bool init = system_state < SYSTEM_RUNNING;
struct module *mod = site_mod->mod;
if (!site_mod->sites) {
@@ -165,6 +169,7 @@ void __static_call_update(struct static_call_key *key, void *tramp, void *func)
if (mod) {
stop = mod->static_call_sites +
mod->num_static_call_sites;
+ init = mod->state == MODULE_STATE_COMING;
}
#endif
@@ -172,25 +177,26 @@ void __static_call_update(struct static_call_key *key, void *tramp, void *func)
site < stop && static_call_key(site) == key; site++) {
void *site_addr = static_call_addr(site);
- if (static_call_is_init(site)) {
- /*
- * Don't write to call sites which were in
- * initmem and have since been freed.
- */
- if (!mod && system_state >= SYSTEM_RUNNING)
- continue;
- if (mod && !within_module_init((unsigned long)site_addr, mod))
- continue;
- }
+ if (!init && static_call_is_init(site))
+ continue;
if (!kernel_text_address((unsigned long)site_addr)) {
- WARN_ONCE(1, "can't patch static call site at %pS",
+ /*
+ * This skips patching built-in __exit, which
+ * is part of init_section_contains() but is
+ * not part of kernel_text_address().
+ *
+ * Skipping built-in __exit is fine since it
+ * will never be executed.
+ */
+ WARN_ONCE(!static_call_is_init(site),
+ "can't patch static call site at %pS",
site_addr);
continue;
}
arch_static_call_transform(site_addr, NULL, func,
- static_call_is_tail(site));
+ static_call_is_tail(site));
}
}
@@ -349,7 +355,7 @@ static int static_call_add_module(struct module *mod)
struct static_call_site *site;
for (site = start; site != stop; site++) {
- unsigned long s_key = (long)site->key + (long)&site->key;
+ unsigned long s_key = __static_call_key(site);
unsigned long addr = s_key & ~STATIC_CALL_SITE_FLAGS;
unsigned long key;
next reply other threads:[~2021-03-21 10:54 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-21 10:53 Ingo Molnar [this message]
2021-03-21 18:45 ` [GIT PULL] locking fixes pr-tracker-bot
-- strict thread matches above, loose matches on Subject: below --
2023-09-22 10:12 Ingo Molnar
2023-09-22 20:19 ` pr-tracker-bot
2021-07-11 13:22 Ingo Molnar
2021-07-11 18:22 ` pr-tracker-bot
2021-04-11 12:14 Ingo Molnar
2021-04-11 18:56 ` pr-tracker-bot
2020-12-27 9:50 Ingo Molnar
2020-12-27 17:27 ` pr-tracker-bot
2020-08-15 11:13 Ingo Molnar
2020-08-16 1:55 ` pr-tracker-bot
2020-01-18 17:53 Ingo Molnar
2020-01-18 21:05 ` pr-tracker-bot
2019-12-17 11:27 Ingo Molnar
2019-12-17 19:20 ` pr-tracker-bot
2019-04-20 7:30 Ingo Molnar
2019-04-20 16:51 ` Linus Torvalds
2019-04-21 18:23 ` Ingo Molnar
2019-04-20 19:25 ` pr-tracker-bot
2019-02-10 8:53 Ingo Molnar
2019-02-10 18:30 ` pr-tracker-bot
2018-10-05 9:36 Ingo Molnar
2018-10-05 23:06 ` Greg Kroah-Hartman
2018-09-15 12:56 Ingo Molnar
2018-07-30 17:49 Ingo Molnar
2018-03-25 8:49 Ingo Molnar
2018-02-15 0:50 Ingo Molnar
2018-01-17 15:24 Ingo Molnar
2018-01-22 9:43 ` Geert Uytterhoeven
2018-01-22 10:39 ` Peter Zijlstra
2018-01-12 13:45 Ingo Molnar
2017-12-15 15:55 Ingo Molnar
2017-10-14 16:01 Ingo Molnar
2017-03-07 20:27 Ingo Molnar
2017-02-28 7:57 Ingo Molnar
2017-02-28 18:37 ` Linus Torvalds
2017-05-03 23:21 ` Linus Torvalds
2017-05-04 5:40 ` Peter Zijlstra
[not found] ` <CA+55aFymvtCAYHdz__3Lj=YqmORB7_A-NXrw=+h+60znJVsDTw@mail.gmail.com>
2017-05-04 22:44 ` Greg Kroah-Hartman
2016-12-07 18:42 Ingo Molnar
2016-10-18 10:55 Ingo Molnar
2016-08-18 20:34 Ingo Molnar
2016-08-12 19:32 Ingo Molnar
2016-06-10 12:45 Ingo Molnar
2016-04-28 17:52 Ingo Molnar
2016-04-23 11:22 Ingo Molnar
2016-03-24 7:47 Ingo Molnar
2015-09-17 7:57 Ingo Molnar
2015-04-18 15:15 Ingo Molnar
2015-02-20 13:37 Ingo Molnar
2015-02-21 0:03 ` Linus Torvalds
2015-02-21 1:51 ` Linus Torvalds
2015-02-23 8:35 ` Christian Borntraeger
2015-02-21 5:07 ` Ingo Molnar
2015-02-21 5:16 ` Ingo Molnar
2015-02-21 5:28 ` Ingo Molnar
2015-01-11 8:39 Ingo Molnar
2014-10-31 11:06 Ingo Molnar
2014-04-16 11:39 Ingo Molnar
2014-01-15 18:15 Ingo Molnar
2009-12-10 19:45 Ingo Molnar
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