* [PATCH 01/11] hrtimer: Add missing annotation to lock_hrtimer_base()
2020-02-09 22:24 ` [PATCH 00/11] Lock warning cleanup Jules Irenge
@ 2020-02-09 22:27 ` Jules Irenge
2020-02-09 22:29 ` [PATCH 02/11] futex: Add missing annotation for wake_futex_pi() Jules Irenge
` (10 subsequent siblings)
11 siblings, 0 replies; 17+ messages in thread
From: Jules Irenge @ 2020-02-09 22:27 UTC (permalink / raw)
To: boqun.feng; +Cc: tglx, linux-kernel, Jules Irenge
Sparse reports several warnings;
warning: context imbalance in lock_hrtimer_base() - wrong count at exit
warning: context imbalance in hrtimer_start_range_ns() - unexpected unlock
warning: context imbalance in hrtimer_try_to_cancel() - unexpected unlock
warning: context imbalance in __hrtimer_get_remaining() - unexpected unlock
The root cause is a missing annotation of lock_hrtimer_base() which
causes also the "unexpected unlock" warnings.
Add the missing __acquires(timer->base) annotation
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
---
kernel/time/hrtimer.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 3a609e7344f3..bb8340e2a3b9 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -160,6 +160,7 @@ static inline bool is_migration_base(struct hrtimer_clock_base *base)
static
struct hrtimer_clock_base *lock_hrtimer_base(const struct hrtimer *timer,
unsigned long *flags)
+ __acquires(timer->base)
{
struct hrtimer_clock_base *base;
--
2.24.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH 02/11] futex: Add missing annotation for wake_futex_pi()
2020-02-09 22:24 ` [PATCH 00/11] Lock warning cleanup Jules Irenge
2020-02-09 22:27 ` [PATCH 01/11] hrtimer: Add missing annotation to lock_hrtimer_base() Jules Irenge
@ 2020-02-09 22:29 ` Jules Irenge
2020-02-09 22:30 ` [PATCH 03/11] futex: Add missing annotation for fixup_pi_state_owner() Jules Irenge
` (9 subsequent siblings)
11 siblings, 0 replies; 17+ messages in thread
From: Jules Irenge @ 2020-02-09 22:29 UTC (permalink / raw)
To: boqun.feng; +Cc: dvhart, peterz, mingo, tglx, linux-kernel, Jules Irenge
Sparse reports a warning at wake_futex_pi()
warning: context imbalance in wake_futex_pi() - unexpected unlock
The root cause is amissing annotation of wake_futex_pi().
Add the missing __releases(&pi_state->pi_mutex.wait_lock) annotation
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
---
kernel/futex.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/kernel/futex.c b/kernel/futex.c
index 0cf84c8664f2..93e7510a5b36 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1550,6 +1550,7 @@ static void mark_wake_futex(struct wake_q_head *wake_q, struct futex_q *q)
* Caller must hold a reference on @pi_state.
*/
static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_pi_state *pi_state)
+ __releases(&pi_state->pi_mutex.wait_lock)
{
u32 uninitialized_var(curval), newval;
struct task_struct *new_owner;
--
2.24.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH 03/11] futex: Add missing annotation for fixup_pi_state_owner()
2020-02-09 22:24 ` [PATCH 00/11] Lock warning cleanup Jules Irenge
2020-02-09 22:27 ` [PATCH 01/11] hrtimer: Add missing annotation to lock_hrtimer_base() Jules Irenge
2020-02-09 22:29 ` [PATCH 02/11] futex: Add missing annotation for wake_futex_pi() Jules Irenge
@ 2020-02-09 22:30 ` Jules Irenge
2020-02-09 22:33 ` [PATCH 04/11] perf/ring_buffer: Add missing annotation to perf_output_end() Jules Irenge
` (8 subsequent siblings)
11 siblings, 0 replies; 17+ messages in thread
From: Jules Irenge @ 2020-02-09 22:30 UTC (permalink / raw)
To: boqun.feng; +Cc: dvhart, peterz, mingo, tglx, linux-kernel, Jules Irenge
Sparse reports a warning at fixup_pi_state_owner()
warning: context imbalance in fixup_pi_state_owner() - unexpected unlock
The root cause is a missing annotation of fixup_pi_state_owner().
Add the missing __must_hold(q->lock_ptr) annotation
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
---
kernel/futex.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/kernel/futex.c b/kernel/futex.c
index 93e7510a5b36..5263cce46c06 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -2440,6 +2440,7 @@ static void unqueue_me_pi(struct futex_q *q)
static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
struct task_struct *argowner)
+ __must_hold(q->lock_ptr)
{
struct futex_pi_state *pi_state = q->pi_state;
u32 uval, uninitialized_var(curval), newval;
--
2.24.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH 04/11] perf/ring_buffer: Add missing annotation to perf_output_end()
2020-02-09 22:24 ` [PATCH 00/11] Lock warning cleanup Jules Irenge
` (2 preceding siblings ...)
2020-02-09 22:30 ` [PATCH 03/11] futex: Add missing annotation for fixup_pi_state_owner() Jules Irenge
@ 2020-02-09 22:33 ` Jules Irenge
2020-02-09 22:37 ` [PATCH 05/11] sched/fair: Add missing annotation for nohz_newidle_balance() Jules Irenge
` (7 subsequent siblings)
11 siblings, 0 replies; 17+ messages in thread
From: Jules Irenge @ 2020-02-09 22:33 UTC (permalink / raw)
To: boqun.feng
Cc: dvhart, peterz, mingo, acme, mark.rutland, alexander.shishkin,
jolsa, namhyung, linux-kernel, Jules Irenge
Sparse reports a warning at perf_output_end()
warning: context imbalance in perf_output_end() - unexpected unlock
The root cause is a missing annotation for perf_output_end()
Add the missing __releases(RCU) annotation
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
---
kernel/events/ring_buffer.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
index 7ffd5c763f93..c09edc49a4fc 100644
--- a/kernel/events/ring_buffer.c
+++ b/kernel/events/ring_buffer.c
@@ -294,7 +294,7 @@ unsigned int perf_output_skip(struct perf_output_handle *handle,
return __output_skip(handle, NULL, len);
}
-void perf_output_end(struct perf_output_handle *handle)
+void perf_output_end(struct perf_output_handle *handle) __releases(RCU)
{
perf_output_put_handle(handle);
rcu_read_unlock();
--
2.24.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH 05/11] sched/fair: Add missing annotation for nohz_newidle_balance()
2020-02-09 22:24 ` [PATCH 00/11] Lock warning cleanup Jules Irenge
` (3 preceding siblings ...)
2020-02-09 22:33 ` [PATCH 04/11] perf/ring_buffer: Add missing annotation to perf_output_end() Jules Irenge
@ 2020-02-09 22:37 ` Jules Irenge
2020-02-09 22:39 ` [PATCH 06/11] sched/deadline: Add missing annotation for dl_task_offline_migration() Jules Irenge
` (6 subsequent siblings)
11 siblings, 0 replies; 17+ messages in thread
From: Jules Irenge @ 2020-02-09 22:37 UTC (permalink / raw)
To: boqun.feng
Cc: juri.lelli, peterz, mingo, vincent.guittot, dietmar.eggemann,
rostedt, bsegall, mgorman, linux-kernel, Jules Irenge
Sparse reports a warning at nohz_newidle_balance()
warning: context imbalance in nohz_newidle_balance() - wrong count at exit
The root cause is a missing annotation
Add the missing __must_hold(this_rq->lock)
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
---
kernel/sched/fair.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index fe4e0d775375..81f8a440469a 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -10050,7 +10050,7 @@ static bool nohz_idle_balance(struct rq *this_rq, enum cpu_idle_type idle)
return true;
}
-static void nohz_newidle_balance(struct rq *this_rq)
+static void nohz_newidle_balance(struct rq *this_rq) __must_hold(&this_rq->lock)
{
int this_cpu = this_rq->cpu;
--
2.24.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH 06/11] sched/deadline: Add missing annotation for dl_task_offline_migration()
2020-02-09 22:24 ` [PATCH 00/11] Lock warning cleanup Jules Irenge
` (4 preceding siblings ...)
2020-02-09 22:37 ` [PATCH 05/11] sched/fair: Add missing annotation for nohz_newidle_balance() Jules Irenge
@ 2020-02-09 22:39 ` Jules Irenge
2020-02-10 8:07 ` Juri Lelli
2020-02-09 22:44 ` [PATCH 07/11] fs_pin: Add missing annotation for pin_kill() declaration Jules Irenge
` (5 subsequent siblings)
11 siblings, 1 reply; 17+ messages in thread
From: Jules Irenge @ 2020-02-09 22:39 UTC (permalink / raw)
To: boqun.feng
Cc: juri.lelli, peterz, mingo, vincent.guittot, dietmar.eggemann,
rostedt, bsegall, mgorman, linux-kernel, Jules Irenge
Sparse reports warning at dl_task_offline_migration()
warning: context imbalance in dl_task_offline_migration()
- unexpected unlock
The root cause is the missing annotation for dl_task_offline_migration()
Add the missing __releases(rq->lock) annotation.
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
---
kernel/sched/deadline.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 43323f875cb9..68ea3a4933db 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -527,6 +527,7 @@ static inline void deadline_queue_pull_task(struct rq *rq)
static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq);
static struct rq *dl_task_offline_migration(struct rq *rq, struct task_struct *p)
+ __releases(rq->lock)
{
struct rq *later_rq = NULL;
struct dl_bw *dl_b;
--
2.24.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* Re: [PATCH 06/11] sched/deadline: Add missing annotation for dl_task_offline_migration()
2020-02-09 22:39 ` [PATCH 06/11] sched/deadline: Add missing annotation for dl_task_offline_migration() Jules Irenge
@ 2020-02-10 8:07 ` Juri Lelli
0 siblings, 0 replies; 17+ messages in thread
From: Juri Lelli @ 2020-02-10 8:07 UTC (permalink / raw)
To: Jules Irenge
Cc: boqun.feng, peterz, mingo, vincent.guittot, dietmar.eggemann,
rostedt, bsegall, mgorman, linux-kernel
Hi,
On 09/02/20 22:39, Jules Irenge wrote:
> Sparse reports warning at dl_task_offline_migration()
>
> warning: context imbalance in dl_task_offline_migration()
> - unexpected unlock
>
> The root cause is the missing annotation for dl_task_offline_migration()
>
> Add the missing __releases(rq->lock) annotation.
>
> Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Acked-by: Juri Lelli <juri.lelli@redhat.com>
Best,
Juri
^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 07/11] fs_pin: Add missing annotation for pin_kill() declaration
2020-02-09 22:24 ` [PATCH 00/11] Lock warning cleanup Jules Irenge
` (5 preceding siblings ...)
2020-02-09 22:39 ` [PATCH 06/11] sched/deadline: Add missing annotation for dl_task_offline_migration() Jules Irenge
@ 2020-02-09 22:44 ` Jules Irenge
2020-02-09 22:45 ` [PATCH 08/11] fs_pin: Add missing annotation for pin_kill() definition Jules Irenge
` (4 subsequent siblings)
11 siblings, 0 replies; 17+ messages in thread
From: Jules Irenge @ 2020-02-09 22:44 UTC (permalink / raw)
To: boqun.feng; +Cc: linux-fsdevel, viro, linux-kernel, Jules Irenge
Sparse reports warnings within the kernel acct.c file
at acct_exit_ns(), __se_sys_acct(), acct_on()
warning: context imbalance in acct_on()
- different lock contexts for basic block
warning: context imbalance in __se_sys_acct()
- different lock contexts for basic block
warning: context imbalance in acct_exit_ns()
- wrong count at exit
The root cause is the missing annotation at pin_kill()
In fact acct_exit_ns(), __se_sys_sys_acct() and acct_on()
do actually call rcu_read_lock()
then call pin_kill() which is defined elsewhere.
A close look at pin_kill()
- called 3 times in the core kernel and 2 times elsewhere-
shows that pin_kill() does actually call rcu_read_unlock().
Adding the annotation at declaration and definition of pin_kill()
not only fixes the warnings
but also improves on the readability of the code
Add the missing annotation __release(RCU)
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
---
include/linux/fs_pin.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/linux/fs_pin.h b/include/linux/fs_pin.h
index bdd09fd2520c..d2fcf1a5112f 100644
--- a/include/linux/fs_pin.h
+++ b/include/linux/fs_pin.h
@@ -21,4 +21,4 @@ static inline void init_fs_pin(struct fs_pin *p, void (*kill)(struct fs_pin *))
void pin_remove(struct fs_pin *);
void pin_insert(struct fs_pin *, struct vfsmount *);
-void pin_kill(struct fs_pin *);
+void pin_kill(struct fs_pin *) __releases(RCU);
--
2.24.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH 08/11] fs_pin: Add missing annotation for pin_kill() definition
2020-02-09 22:24 ` [PATCH 00/11] Lock warning cleanup Jules Irenge
` (6 preceding siblings ...)
2020-02-09 22:44 ` [PATCH 07/11] fs_pin: Add missing annotation for pin_kill() declaration Jules Irenge
@ 2020-02-09 22:45 ` Jules Irenge
2020-02-09 22:48 ` [PATCH 09/11] kasan: add missing annotation for start_report() Jules Irenge
` (3 subsequent siblings)
11 siblings, 0 replies; 17+ messages in thread
From: Jules Irenge @ 2020-02-09 22:45 UTC (permalink / raw)
To: boqun.feng; +Cc: linux-fsdevel, viro, linux-kernel, Jules Irenge
Sparse reports a warning at pin_kill()
warning: context imbalance in pin_kil() - unexpected unlock
The root cause is a missing annotation for pin_kill()
Add the missing annotation __releases(RCU)
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
---
fs/fs_pin.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/fs_pin.c b/fs/fs_pin.c
index 47ef3c71ce90..972168453fba 100644
--- a/fs/fs_pin.c
+++ b/fs/fs_pin.c
@@ -27,7 +27,7 @@ void pin_insert(struct fs_pin *pin, struct vfsmount *m)
spin_unlock(&pin_lock);
}
-void pin_kill(struct fs_pin *p)
+void pin_kill(struct fs_pin *p) __releases(RCU)
{
wait_queue_entry_t wait;
--
2.24.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH 09/11] kasan: add missing annotation for start_report()
2020-02-09 22:24 ` [PATCH 00/11] Lock warning cleanup Jules Irenge
` (7 preceding siblings ...)
2020-02-09 22:45 ` [PATCH 08/11] fs_pin: Add missing annotation for pin_kill() definition Jules Irenge
@ 2020-02-09 22:48 ` Jules Irenge
2020-02-10 7:27 ` Dmitry Vyukov
2020-02-09 22:49 ` [PATCH 10/11] kasan: add missing annotation for end_report() Jules Irenge
` (2 subsequent siblings)
11 siblings, 1 reply; 17+ messages in thread
From: Jules Irenge @ 2020-02-09 22:48 UTC (permalink / raw)
To: boqun.feng
Cc: linux-kernel, linux-mm, kasan-dev, akpm, dvyukov, glider,
aryabinin, Jules Irenge
Sparse reports a warning at start_report()
warning: context imbalance in start_report() - wrong count at exit
The root cause is a missing annotation at start_report()
Add the missing annotation __acquires(&report_lock)
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
---
mm/kasan/report.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 5ef9f24f566b..5451624c4e09 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -77,7 +77,7 @@ static void print_error_description(struct kasan_access_info *info)
static DEFINE_SPINLOCK(report_lock);
-static void start_report(unsigned long *flags)
+static void start_report(unsigned long *flags) __acquires(&report_lock)
{
/*
* Make sure we don't end up in loop.
--
2.24.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* Re: [PATCH 09/11] kasan: add missing annotation for start_report()
2020-02-09 22:48 ` [PATCH 09/11] kasan: add missing annotation for start_report() Jules Irenge
@ 2020-02-10 7:27 ` Dmitry Vyukov
0 siblings, 0 replies; 17+ messages in thread
From: Dmitry Vyukov @ 2020-02-10 7:27 UTC (permalink / raw)
To: Jules Irenge
Cc: Boqun Feng, LKML, Linux-MM, kasan-dev, Andrew Morton,
Alexander Potapenko, Andrey Ryabinin
On Sun, Feb 9, 2020 at 11:48 PM Jules Irenge <jbi.octave@gmail.com> wrote:
>
> Sparse reports a warning at start_report()
>
> warning: context imbalance in start_report() - wrong count at exit
>
> The root cause is a missing annotation at start_report()
>
> Add the missing annotation __acquires(&report_lock)
>
> Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
> ---
> mm/kasan/report.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/kasan/report.c b/mm/kasan/report.c
> index 5ef9f24f566b..5451624c4e09 100644
> --- a/mm/kasan/report.c
> +++ b/mm/kasan/report.c
> @@ -77,7 +77,7 @@ static void print_error_description(struct kasan_access_info *info)
>
> static DEFINE_SPINLOCK(report_lock);
>
> -static void start_report(unsigned long *flags)
> +static void start_report(unsigned long *flags) __acquires(&report_lock)
> {
> /*
> * Make sure we don't end up in loop.
> --
> 2.24.1
>
^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 10/11] kasan: add missing annotation for end_report()
2020-02-09 22:24 ` [PATCH 00/11] Lock warning cleanup Jules Irenge
` (8 preceding siblings ...)
2020-02-09 22:48 ` [PATCH 09/11] kasan: add missing annotation for start_report() Jules Irenge
@ 2020-02-09 22:49 ` Jules Irenge
2020-02-10 7:27 ` Dmitry Vyukov
2020-02-09 22:50 ` [PATCH 11/11] futex: Add missing annotation for futex_wait_queue_me() Jules Irenge
2020-02-10 5:06 ` [PATCH 00/11] Lock warning cleanup Boqun Feng
11 siblings, 1 reply; 17+ messages in thread
From: Jules Irenge @ 2020-02-09 22:49 UTC (permalink / raw)
To: boqun.feng
Cc: linux-kernel, linux-mm, kasan-dev, akpm, dvyukov, glider,
aryabinin, Jules Irenge
Sparse reports a warning at end_report()
warning: context imbalance in end_report() - unexpected lock
The root cause is a missing annotation at end_report()
Add the missing annotation __releases(&report_lock)
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
---
mm/kasan/report.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 5451624c4e09..8adaa4eaee31 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -87,7 +87,7 @@ static void start_report(unsigned long *flags) __acquires(&report_lock)
pr_err("==================================================================\n");
}
-static void end_report(unsigned long *flags)
+static void end_report(unsigned long *flags) __releases(&report_lock)
{
pr_err("==================================================================\n");
add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
--
2.24.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* Re: [PATCH 10/11] kasan: add missing annotation for end_report()
2020-02-09 22:49 ` [PATCH 10/11] kasan: add missing annotation for end_report() Jules Irenge
@ 2020-02-10 7:27 ` Dmitry Vyukov
0 siblings, 0 replies; 17+ messages in thread
From: Dmitry Vyukov @ 2020-02-10 7:27 UTC (permalink / raw)
To: Jules Irenge
Cc: Boqun Feng, LKML, Linux-MM, kasan-dev, Andrew Morton,
Alexander Potapenko, Andrey Ryabinin
On Sun, Feb 9, 2020 at 11:49 PM Jules Irenge <jbi.octave@gmail.com> wrote:
>
> Sparse reports a warning at end_report()
>
> warning: context imbalance in end_report() - unexpected lock
>
> The root cause is a missing annotation at end_report()
>
> Add the missing annotation __releases(&report_lock)
>
> Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
> ---
> mm/kasan/report.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/kasan/report.c b/mm/kasan/report.c
> index 5451624c4e09..8adaa4eaee31 100644
> --- a/mm/kasan/report.c
> +++ b/mm/kasan/report.c
> @@ -87,7 +87,7 @@ static void start_report(unsigned long *flags) __acquires(&report_lock)
> pr_err("==================================================================\n");
> }
>
> -static void end_report(unsigned long *flags)
> +static void end_report(unsigned long *flags) __releases(&report_lock)
> {
> pr_err("==================================================================\n");
> add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
> --
> 2.24.1
>
^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 11/11] futex: Add missing annotation for futex_wait_queue_me()
2020-02-09 22:24 ` [PATCH 00/11] Lock warning cleanup Jules Irenge
` (9 preceding siblings ...)
2020-02-09 22:49 ` [PATCH 10/11] kasan: add missing annotation for end_report() Jules Irenge
@ 2020-02-09 22:50 ` Jules Irenge
2020-02-10 5:06 ` [PATCH 00/11] Lock warning cleanup Boqun Feng
11 siblings, 0 replies; 17+ messages in thread
From: Jules Irenge @ 2020-02-09 22:50 UTC (permalink / raw)
To: boqun.feng; +Cc: dvhart, peterz, mingo, tglx, linux-kernel, Jules Irenge
Sparse reports a warning at futex_wait_queue_me()
warning: context imbalance in futex_wait_queue_me() - unexpected unlock
The root cause is a missing annotation at futex_wait_queue_me()
Add the missing annotation __releases(&hb->lock)
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
---
kernel/futex.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/kernel/futex.c b/kernel/futex.c
index 5263cce46c06..16c6c40dbd68 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -2679,6 +2679,7 @@ static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
*/
static void futex_wait_queue_me(struct futex_hash_bucket *hb, struct futex_q *q,
struct hrtimer_sleeper *timeout)
+ __releases(&hb->lock)
{
/*
* The task state is guaranteed to be set before another task can
--
2.24.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* Re: [PATCH 00/11] Lock warning cleanup
2020-02-09 22:24 ` [PATCH 00/11] Lock warning cleanup Jules Irenge
` (10 preceding siblings ...)
2020-02-09 22:50 ` [PATCH 11/11] futex: Add missing annotation for futex_wait_queue_me() Jules Irenge
@ 2020-02-10 5:06 ` Boqun Feng
2020-02-10 23:09 ` Jules Irenge
11 siblings, 1 reply; 17+ messages in thread
From: Boqun Feng @ 2020-02-10 5:06 UTC (permalink / raw)
To: Jules Irenge
Cc: linux-kernel, linux-mm, kasan-dev, akpm, dvyukov, glider,
aryabinin, bsegall, rostedt, dietmar.eggemann, vincent.guittot,
juri.lelli, peterz, mingo, mgorman, dvhart, tglx, namhyung,
jolsa, alexander.shishkin, mark.rutland, acme, viro,
linux-fsdevel
Hi Jules,
On Sun, Feb 09, 2020 at 10:24:42PM +0000, Jules Irenge wrote:
> This patch series adds missing annotations to functions that register warnings of context imbalance when built with Sparse tool.
> The adds fix the warnings and give insight on what the functions are actually doing.
>
> 1. Within the futex subsystem, a __releases(&pi_state->.pi_mutex.wait_lock) is added because wake_futex_pi() only releases the lock at exit,
> must_hold(q->lock_ptr) have been added to fixup_pi_state_owner() because the lock is held at entry and exit;
> a __releases(&hb->lock) added to futex_wait_queue_me() as it only releases the lock.
>
> 2. Within fs_pin, a __releases(RCU) is added because the function exit RCU critical section at exit.
>
> 3. In kasan, an __acquires(&report_lock) has been added to start_report() and __releases(&report_lock) to end_report()
>
> 4. Within ring_buffer subsystem, a __releases(RCU) has been added perf_output_end()
>
> 5. schedule subsystem recorded an addition of the __releases(rq->lock) annotation and a __must_hold(this_rq->lock)
>
> 6. At hrtimer subsystem, __acquires(timer) is added to lock_hrtimer_base() as the function acquire the lock but never releases it.
> Jules Irenge (11):
> hrtimer: Add missing annotation to lock_hrtimer_base()
> futex: Add missing annotation for wake_futex_pi()
> futex: Add missing annotation for fixup_pi_state_owner()
Given that those three patches have been sent and reviewed, please do
increase the version number (this time, for example, using v2) when
sending the updated ones. Also please add a few sentences after the
commit log describing what you have changed between versions.
Here is an example:
https://lore.kernel.org/lkml/20200124231834.63628-4-pmalani@chromium.org/
Regards,
Boqun
> perf/ring_buffer: Add missing annotation to perf_output_end()
> sched/fair: Add missing annotation for nohz_newidle_balance()
> sched/deadline: Add missing annotation for dl_task_offline_migration()
> fs_pin: Add missing annotation for pin_kill() declaration
> fs_pin: Add missing annotation for pin_kill() definition
> kasan: add missing annotation for start_report()
> kasan: add missing annotation for end_report()
> futex: Add missing annotation for futex_wait_queue_me()
>
> fs/fs_pin.c | 2 +-
> include/linux/fs_pin.h | 2 +-
> kernel/events/ring_buffer.c | 2 +-
> kernel/futex.c | 3 +++
> kernel/sched/deadline.c | 1 +
> kernel/sched/fair.c | 2 +-
> kernel/time/hrtimer.c | 1 +
> mm/kasan/report.c | 4 ++--
> 8 files changed, 11 insertions(+), 6 deletions(-)
>
> --
> 2.24.1
>
^ permalink raw reply [flat|nested] 17+ messages in thread* Re: [PATCH 00/11] Lock warning cleanup
2020-02-10 5:06 ` [PATCH 00/11] Lock warning cleanup Boqun Feng
@ 2020-02-10 23:09 ` Jules Irenge
0 siblings, 0 replies; 17+ messages in thread
From: Jules Irenge @ 2020-02-10 23:09 UTC (permalink / raw)
To: Boqun Feng
Cc: Jules Irenge, linux-kernel, linux-mm, kasan-dev, akpm, dvyukov,
glider, aryabinin, bsegall, rostedt, dietmar.eggemann,
vincent.guittot, juri.lelli, peterz, mingo, mgorman, dvhart,
tglx, namhyung, jolsa, alexander.shishkin, mark.rutland, acme,
viro, linux-fsdevel
On Mon, 10 Feb 2020, Boqun Feng wrote:
> Hi Jules,
>
> On Sun, Feb 09, 2020 at 10:24:42PM +0000, Jules Irenge wrote:
> > This patch series adds missing annotations to functions that register warnings of context imbalance when built with Sparse tool.
> > The adds fix the warnings and give insight on what the functions are actually doing.
> >
> > 1. Within the futex subsystem, a __releases(&pi_state->.pi_mutex.wait_lock) is added because wake_futex_pi() only releases the lock at exit,
> > must_hold(q->lock_ptr) have been added to fixup_pi_state_owner() because the lock is held at entry and exit;
> > a __releases(&hb->lock) added to futex_wait_queue_me() as it only releases the lock.
> >
> > 2. Within fs_pin, a __releases(RCU) is added because the function exit RCU critical section at exit.
> >
> > 3. In kasan, an __acquires(&report_lock) has been added to start_report() and __releases(&report_lock) to end_report()
> >
> > 4. Within ring_buffer subsystem, a __releases(RCU) has been added perf_output_end()
> >
> > 5. schedule subsystem recorded an addition of the __releases(rq->lock) annotation and a __must_hold(this_rq->lock)
> >
> > 6. At hrtimer subsystem, __acquires(timer) is added to lock_hrtimer_base() as the function acquire the lock but never releases it.
> > Jules Irenge (11):
> > hrtimer: Add missing annotation to lock_hrtimer_base()
> > futex: Add missing annotation for wake_futex_pi()
> > futex: Add missing annotation for fixup_pi_state_owner()
>
> Given that those three patches have been sent and reviewed, please do
> increase the version number (this time, for example, using v2) when
> sending the updated ones. Also please add a few sentences after the
> commit log describing what you have changed between versions.
>
> Here is an example:
>
> https://lore.kernel.org/lkml/20200124231834.63628-4-pmalani@chromium.org/
>
> Regards,
> Boqun
>
> > perf/ring_buffer: Add missing annotation to perf_output_end()
> > sched/fair: Add missing annotation for nohz_newidle_balance()
> > sched/deadline: Add missing annotation for dl_task_offline_migration()
> > fs_pin: Add missing annotation for pin_kill() declaration
> > fs_pin: Add missing annotation for pin_kill() definition
> > kasan: add missing annotation for start_report()
> > kasan: add missing annotation for end_report()
> > futex: Add missing annotation for futex_wait_queue_me()
> >
> > fs/fs_pin.c | 2 +-
> > include/linux/fs_pin.h | 2 +-
> > kernel/events/ring_buffer.c | 2 +-
> > kernel/futex.c | 3 +++
> > kernel/sched/deadline.c | 1 +
> > kernel/sched/fair.c | 2 +-
> > kernel/time/hrtimer.c | 1 +
> > mm/kasan/report.c | 4 ++--
> > 8 files changed, 11 insertions(+), 6 deletions(-)
> >
> > --
> > 2.24.1
> >
>
Thanks for the feedback, I take good notes. I am working on the
second version.
Kind regards,
Jules
^ permalink raw reply [flat|nested] 17+ messages in thread