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linux59-tkg: Add back fsync patchset. Thanks to @terencode for his restore futex_key patch :frog: :heart:
2020-10-12 19:39:36 +02:00
From 4e715df2b89c6325cf3ca0516338e90bc7567fdb Mon Sep 17 00:00:00 2001
From: Térence Clastres <t.clastres@gmail.com>
Date: Mon, 12 Oct 2020 18:58:11 +0200
Subject: Restore futex_key
diff --git a/kernel/futex.c b/kernel/futex.c
index a5876694a60e..d303493d50fa 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -118,7 +118,8 @@
*
* Where (A) orders the waiters increment and the futex value read through
* atomic operations (see hb_waiters_inc) and where (B) orders the write
- * to futex and the waiters read (see hb_waiters_pending()).
+ * to futex and the waiters read -- this is done by the barriers for both
+ * shared and private futexes in get_futex_key_refs().
*
* This yields the following case (where X:=waiters, Y:=futex):
*
@@ -341,10 +342,6 @@ static inline void hb_waiters_dec(struct futex_hash_bucket *hb)
static inline int hb_waiters_pending(struct futex_hash_bucket *hb)
{
#ifdef CONFIG_SMP
- /*
- * Full barrier (B), see the ordering comment above.
- */
- smp_mb();
return atomic_read(&hb->waiters);
#else
return 1;
@@ -382,6 +379,68 @@ static inline int match_futex(union futex_key *key1, union futex_key *key2)
&& key1->both.offset == key2->both.offset);
}
+/*
+ * Take a reference to the resource addressed by a key.
+ * Can be called while holding spinlocks.
+ *
+ */
+static void get_futex_key_refs(union futex_key *key)
+{
+ if (!key->both.ptr)
+ return;
+
+ /*
+ * On MMU less systems futexes are always "private" as there is no per
+ * process address space. We need the smp wmb nevertheless - yes,
+ * arch/blackfin has MMU less SMP ...
+ */
+ if (!IS_ENABLED(CONFIG_MMU)) {
+ smp_mb(); /* explicit smp_mb(); (B) */
+ return;
+ }
+
+ switch (key->both.offset & (FUT_OFF_INODE|FUT_OFF_MMSHARED)) {
+ case FUT_OFF_INODE:
+ smp_mb(); /* explicit smp_mb(); (B) */
+ break;
+ case FUT_OFF_MMSHARED:
+ smp_mb(); /* explicit smp_mb(); (B) */
+ break;
+ default:
+ /*
+ * Private futexes do not hold reference on an inode or
+ * mm, therefore the only purpose of calling get_futex_key_refs
+ * is because we need the barrier for the lockless waiter check.
+ */
+ smp_mb(); /* explicit smp_mb(); (B) */
+ }
+}
+
+/*
+ * Drop a reference to the resource addressed by a key.
+ * The hash bucket spinlock must not be held. This is
+ * a no-op for private futexes, see comment in the get
+ * counterpart.
+ */
+static void drop_futex_key_refs(union futex_key *key)
+{
+ if (!key->both.ptr) {
+ /* If we're here then we tried to put a key we failed to get */
+ WARN_ON_ONCE(1);
+ return;
+ }
+
+ if (!IS_ENABLED(CONFIG_MMU))
+ return;
+
+ switch (key->both.offset & (FUT_OFF_INODE|FUT_OFF_MMSHARED)) {
+ case FUT_OFF_INODE:
+ break;
+ case FUT_OFF_MMSHARED:
+ break;
+ }
+}
+
enum futex_access {
FUTEX_READ,
FUTEX_WRITE
@@ -516,6 +575,7 @@ static int get_futex_key(u32 __user *uaddr, bool fshared, union futex_key *key,
if (!fshared) {
key->private.mm = mm;
key->private.address = address;
+ get_futex_key_refs(key); /* implies smp_mb(); (B) */
return 0;
}
@@ -655,11 +715,18 @@ static int get_futex_key(u32 __user *uaddr, bool fshared, union futex_key *key,
rcu_read_unlock();
}
+ get_futex_key_refs(key); /* implies smp_mb(); (B) */
+
out:
put_page(page);
return err;
}
+static inline void put_futex_key(union futex_key *key)
+{
+ drop_futex_key_refs(key);
+}
+
/**
* fault_in_user_writeable() - Fault in user address and verify RW access
* @uaddr: pointer to faulting user space address
@@ -1590,13 +1657,13 @@ futex_wake(u32 __user *uaddr, unsigned int flags, int nr_wake, u32 bitset)
ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &key, FUTEX_READ);
if (unlikely(ret != 0))
- return ret;
+ goto out;
hb = hash_futex(&key);
/* Make sure we really have tasks to wakeup */
if (!hb_waiters_pending(hb))
- return ret;
+ goto out_put_key;
spin_lock(&hb->lock);
@@ -1619,6 +1686,9 @@ futex_wake(u32 __user *uaddr, unsigned int flags, int nr_wake, u32 bitset)
spin_unlock(&hb->lock);
wake_up_q(&wake_q);
+out_put_key:
+ put_futex_key(&key);
+out:
return ret;
}
@@ -1685,10 +1755,10 @@ futex_wake_op(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2,
retry:
ret = get_futex_key(uaddr1, flags & FLAGS_SHARED, &key1, FUTEX_READ);
if (unlikely(ret != 0))
- return ret;
+ goto out;
ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, FUTEX_WRITE);
if (unlikely(ret != 0))
- return ret;
+ goto out_put_key1;
hb1 = hash_futex(&key1);
hb2 = hash_futex(&key2);
@@ -1706,13 +1776,13 @@ futex_wake_op(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2,
* an MMU, but we might get them from range checking
*/
ret = op_ret;
- return ret;
+ goto out_put_keys;
}
if (op_ret == -EFAULT) {
ret = fault_in_user_writeable(uaddr2);
if (ret)
- return ret;
+ goto out_put_keys;
}
if (!(flags & FLAGS_SHARED)) {
@@ -1720,6 +1790,8 @@ futex_wake_op(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2,
goto retry_private;
}
+ put_futex_key(&key2);
+ put_futex_key(&key1);
cond_resched();
goto retry;
}
@@ -1755,6 +1827,11 @@ futex_wake_op(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2,
out_unlock:
double_unlock_hb(hb1, hb2);
wake_up_q(&wake_q);
+out_put_keys:
+ put_futex_key(&key2);
+out_put_key1:
+ put_futex_key(&key1);
+out:
return ret;
}
@@ -1781,6 +1858,7 @@ void requeue_futex(struct futex_q *q, struct futex_hash_bucket *hb1,
plist_add(&q->list, &hb2->chain);
q->lock_ptr = &hb2->lock;
}
+ get_futex_key_refs(key2);
q->key = *key2;
}
@@ -1802,6 +1880,7 @@ static inline
void requeue_pi_wake_futex(struct futex_q *q, union futex_key *key,
struct futex_hash_bucket *hb)
{
+ get_futex_key_refs(key);
q->key = *key;
__unqueue_futex(q);
@@ -1912,7 +1991,7 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
u32 *cmpval, int requeue_pi)
{
union futex_key key1 = FUTEX_KEY_INIT, key2 = FUTEX_KEY_INIT;
- int task_count = 0, ret;
+ int drop_count = 0, task_count = 0, ret;
struct futex_pi_state *pi_state = NULL;
struct futex_hash_bucket *hb1, *hb2;
struct futex_q *this, *next;
@@ -1961,18 +2040,20 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
retry:
ret = get_futex_key(uaddr1, flags & FLAGS_SHARED, &key1, FUTEX_READ);
if (unlikely(ret != 0))
- return ret;
+ goto out;
ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2,
requeue_pi ? FUTEX_WRITE : FUTEX_READ);
if (unlikely(ret != 0))
- return ret;
+ goto out_put_key1;
/*
* The check above which compares uaddrs is not sufficient for
* shared futexes. We need to compare the keys:
*/
- if (requeue_pi && match_futex(&key1, &key2))
- return -EINVAL;
+ if (requeue_pi && match_futex(&key1, &key2)) {
+ ret = -EINVAL;
+ goto out_put_keys;
+ }
hb1 = hash_futex(&key1);
hb2 = hash_futex(&key2);
@@ -1992,11 +2073,13 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
ret = get_user(curval, uaddr1);
if (ret)
- return ret;
+ goto out_put_keys;
if (!(flags & FLAGS_SHARED))
goto retry_private;
+ put_futex_key(&key2);
+ put_futex_key(&key1);
goto retry;
}
if (curval != *cmpval) {
@@ -2029,6 +2112,7 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
*/
if (ret > 0) {
WARN_ON(pi_state);
+ drop_count++;
task_count++;
/*
* If we acquired the lock, then the user space value
@@ -2055,10 +2139,12 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
case -EFAULT:
double_unlock_hb(hb1, hb2);
hb_waiters_dec(hb2);
+ put_futex_key(&key2);
+ put_futex_key(&key1);
ret = fault_in_user_writeable(uaddr2);
if (!ret)
goto retry;
- return ret;
+ goto out;
case -EBUSY:
case -EAGAIN:
/*
@@ -2069,6 +2155,8 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
*/
double_unlock_hb(hb1, hb2);
hb_waiters_dec(hb2);
+ put_futex_key(&key2);
+ put_futex_key(&key1);
/*
* Handle the case where the owner is in the middle of
* exiting. Wait for the exit to complete otherwise
@@ -2144,6 +2232,7 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
* doing so.
*/
requeue_pi_wake_futex(this, &key2, hb2);
+ drop_count++;
continue;
} else if (ret) {
/*
@@ -2164,6 +2253,7 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
}
}
requeue_futex(this, hb1, hb2, &key2);
+ drop_count++;
}
/*
@@ -2177,6 +2267,21 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
double_unlock_hb(hb1, hb2);
wake_up_q(&wake_q);
hb_waiters_dec(hb2);
+
+ /*
+ * drop_futex_key_refs() must be called outside the spinlocks. During
+ * the requeue we moved futex_q's from the hash bucket at key1 to the
+ * one at key2 and updated their key pointer. We no longer need to
+ * hold the references to key1.
+ */
+ while (--drop_count >= 0)
+ drop_futex_key_refs(&key1);
+
+out_put_keys:
+ put_futex_key(&key2);
+out_put_key1:
+ put_futex_key(&key1);
+out:
return ret ? ret : task_count;
}
@@ -2301,6 +2406,7 @@ static int unqueue_me(struct futex_q *q)
ret = 1;
}
+ drop_futex_key_refs(&q->key);
return ret;
}
@@ -2522,7 +2628,7 @@ static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
*/
if (q->pi_state->owner != current)
ret = fixup_pi_state_owner(uaddr, q, current);
- return ret ? ret : locked;
+ goto out;
}
/*
@@ -2535,7 +2641,7 @@ static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
*/
if (q->pi_state->owner == current) {
ret = fixup_pi_state_owner(uaddr, q, NULL);
- return ret;
+ goto out;
}
/*
@@ -2549,7 +2655,8 @@ static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
q->pi_state->owner);
}
- return ret;
+out:
+ return ret ? ret : locked;
}
/**
@@ -2646,11 +2753,12 @@ static int futex_wait_setup(u32 __user *uaddr, u32 val, unsigned int flags,
ret = get_user(uval, uaddr);
if (ret)
- return ret;
+ goto out;
if (!(flags & FLAGS_SHARED))
goto retry_private;
+ put_futex_key(&q->key);
goto retry;
}
@@ -2659,6 +2767,9 @@ static int futex_wait_setup(u32 __user *uaddr, u32 val, unsigned int flags,
ret = -EWOULDBLOCK;
}
+out:
+ if (ret)
+ put_futex_key(&q->key);
return ret;
}
@@ -2803,6 +2914,7 @@ static int futex_lock_pi(u32 __user *uaddr, unsigned int flags,
* - EAGAIN: The user space value changed.
*/
queue_unlock(hb);
+ put_futex_key(&q.key);
/*
* Handle the case where the owner is in the middle of
* exiting. Wait for the exit to complete otherwise
@@ -2910,11 +3022,13 @@ static int futex_lock_pi(u32 __user *uaddr, unsigned int flags,
put_pi_state(pi_state);
}
- goto out;
+ goto out_put_key;
out_unlock_put_key:
queue_unlock(hb);
+out_put_key:
+ put_futex_key(&q.key);
out:
if (to) {
hrtimer_cancel(&to->timer);
@@ -2927,11 +3041,12 @@ static int futex_lock_pi(u32 __user *uaddr, unsigned int flags,
ret = fault_in_user_writeable(uaddr);
if (ret)
- goto out;
+ goto out_put_key;
if (!(flags & FLAGS_SHARED))
goto retry_private;
+ put_futex_key(&q.key);
goto retry;
}
@@ -3060,13 +3175,16 @@ static int futex_unlock_pi(u32 __user *uaddr, unsigned int flags)
out_unlock:
spin_unlock(&hb->lock);
out_putkey:
+ put_futex_key(&key);
return ret;
pi_retry:
+ put_futex_key(&key);
cond_resched();
goto retry;
pi_faulted:
+ put_futex_key(&key);
ret = fault_in_user_writeable(uaddr);
if (!ret)
@@ -3208,7 +3326,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
*/
ret = futex_wait_setup(uaddr, val, flags, &q, &hb);
if (ret)
- goto out;
+ goto out_key2;
/*
* The check above which compares uaddrs is not sufficient for
@@ -3217,7 +3335,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
if (match_futex(&q.key, &key2)) {
queue_unlock(hb);
ret = -EINVAL;
- goto out;
+ goto out_put_keys;
}
/* Queue the futex_q, drop the hb lock, wait for wakeup. */
@@ -3227,7 +3345,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
ret = handle_early_requeue_pi_wakeup(hb, &q, &key2, to);
spin_unlock(&hb->lock);
if (ret)
- goto out;
+ goto out_put_keys;
/*
* In order for us to be here, we know our q.key == key2, and since
@@ -3317,6 +3435,11 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
ret = -EWOULDBLOCK;
}
+out_put_keys:
+ put_futex_key(&q.key);
+out_key2:
+ put_futex_key(&key2);
+
out:
if (to) {
hrtimer_cancel(&to->timer);
From f7f49141a5dbe9c99d78196b58c44307fb2e6be3 Mon Sep 17 00:00:00 2001
From: Tk-Glitch <ti3nou@gmail.com>
Date: Mon, 20 Apr 2020 14:09:11 +0200
Subject: Import Fsync v3 patchset - Squashed from https://gitlab.collabora.com/tonyk/linux/-/commits/futex-proton-v3
diff --git a/include/uapi/linux/futex.h b/include/uapi/linux/futex.h
index a89eb0accd5e2ee527be1e3e11b1117ff5bf94b4..580001e89c6caed57dd8b3cb491d65dce846caff 100644
--- a/include/uapi/linux/futex.h
+++ b/include/uapi/linux/futex.h
@@ -21,6 +21,7 @@
#define FUTEX_WAKE_BITSET 10
#define FUTEX_WAIT_REQUEUE_PI 11
#define FUTEX_CMP_REQUEUE_PI 12
+#define FUTEX_WAIT_MULTIPLE 13
#define FUTEX_PRIVATE_FLAG 128
#define FUTEX_CLOCK_REALTIME 256
@@ -40,6 +41,8 @@
FUTEX_PRIVATE_FLAG)
#define FUTEX_CMP_REQUEUE_PI_PRIVATE (FUTEX_CMP_REQUEUE_PI | \
FUTEX_PRIVATE_FLAG)
+#define FUTEX_WAIT_MULTIPLE_PRIVATE (FUTEX_WAIT_MULTIPLE | \
+ FUTEX_PRIVATE_FLAG)
/*
* Support for robust futexes: the kernel cleans up held futexes at
@@ -150,4 +153,21 @@ struct robust_list_head {
(((op & 0xf) << 28) | ((cmp & 0xf) << 24) \
| ((oparg & 0xfff) << 12) | (cmparg & 0xfff))
+/*
+ * Maximum number of multiple futexes to wait for
+ */
+#define FUTEX_MULTIPLE_MAX_COUNT 128
+
+/**
+ * struct futex_wait_block - Block of futexes to be waited for
+ * @uaddr: User address of the futex
+ * @val: Futex value expected by userspace
+ * @bitset: Bitset for the optional bitmasked wakeup
+ */
+struct futex_wait_block {
+ __u32 __user *uaddr;
+ __u32 val;
+ __u32 bitset;
+};
+
#endif /* _UAPI_LINUX_FUTEX_H */
diff --git a/kernel/futex.c b/kernel/futex.c
index 0cf84c8664f207c574325b899ef2e57f01295a94..58cf9eb2b851b4858e29b5ef4114a29a92e676ba 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -215,6 +215,8 @@ struct futex_pi_state {
* @rt_waiter: rt_waiter storage for use with requeue_pi
* @requeue_pi_key: the requeue_pi target futex key
* @bitset: bitset for the optional bitmasked wakeup
+ * @uaddr: userspace address of futex
+ * @uval: expected futex's value
*
* We use this hashed waitqueue, instead of a normal wait_queue_entry_t, so
* we can wake only the relevant ones (hashed queues may be shared).
@@ -237,6 +239,8 @@ struct futex_q {
struct rt_mutex_waiter *rt_waiter;
union futex_key *requeue_pi_key;
u32 bitset;
+ u32 __user *uaddr;
+ u32 uval;
} __randomize_layout;
static const struct futex_q futex_q_init = {
@@ -2420,6 +2424,29 @@ static int unqueue_me(struct futex_q *q)
return ret;
}
+/**
+ * unqueue_multiple() - Remove several futexes from their futex_hash_bucket
+ * @q: The list of futexes to unqueue
+ * @count: Number of futexes in the list
+ *
+ * Helper to unqueue a list of futexes. This can't fail.
+ *
+ * Return:
+ * - >=0 - Index of the last futex that was awoken;
+ * - -1 - If no futex was awoken
+ */
+static int unqueue_multiple(struct futex_q *q, int count)
+{
+ int ret = -1;
+ int i;
+
+ for (i = 0; i < count; i++) {
+ if (!unqueue_me(&q[i]))
+ ret = i;
+ }
+ return ret;
+}
+
/*
* PI futexes can not be requeued and must remove themself from the
* hash bucket. The hash bucket lock (i.e. lock_ptr) is held on entry
@@ -2783,6 +2810,211 @@ static int futex_wait_setup(u32 __user *uaddr, u32 val, unsigned int flags,
return ret;
}
+/**
+ * futex_wait_multiple_setup() - Prepare to wait and enqueue multiple futexes
+ * @qs: The corresponding futex list
+ * @count: The size of the lists
+ * @flags: Futex flags (FLAGS_SHARED, etc.)
+ * @awaken: Index of the last awoken futex
+ *
+ * Prepare multiple futexes in a single step and enqueue them. This may fail if
+ * the futex list is invalid or if any futex was already awoken. On success the
+ * task is ready to interruptible sleep.
+ *
+ * Return:
+ * - 1 - One of the futexes was awaken by another thread
+ * - 0 - Success
+ * - <0 - -EFAULT, -EWOULDBLOCK or -EINVAL
+ */
+static int futex_wait_multiple_setup(struct futex_q *qs, int count,
+ unsigned int flags, int *awaken)
+{
+ struct futex_hash_bucket *hb;
+ int ret, i;
+ u32 uval;
+
+ /*
+ * Enqueuing multiple futexes is tricky, because we need to
+ * enqueue each futex in the list before dealing with the next
+ * one to avoid deadlocking on the hash bucket. But, before
+ * enqueuing, we need to make sure that current->state is
+ * TASK_INTERRUPTIBLE, so we don't absorb any awake events, which
+ * cannot be done before the get_futex_key of the next key,
+ * because it calls get_user_pages, which can sleep. Thus, we
+ * fetch the list of futexes keys in two steps, by first pinning
+ * all the memory keys in the futex key, and only then we read
+ * each key and queue the corresponding futex.
+ */
+retry:
+ for (i = 0; i < count; i++) {
+ qs[i].key = FUTEX_KEY_INIT;
+ ret = get_futex_key(qs[i].uaddr, flags & FLAGS_SHARED,
+ &qs[i].key, FUTEX_READ);
+ if (unlikely(ret)) {
+ for (--i; i >= 0; i--)
+ put_futex_key(&qs[i].key);
+ return ret;
+ }
+ }
+
+ set_current_state(TASK_INTERRUPTIBLE);
+
+ for (i = 0; i < count; i++) {
+ struct futex_q *q = &qs[i];
+
+ hb = queue_lock(q);
+
+ ret = get_futex_value_locked(&uval, q->uaddr);
+ if (ret) {
+ /*
+ * We need to try to handle the fault, which
+ * cannot be done without sleep, so we need to
+ * undo all the work already done, to make sure
+ * we don't miss any wake ups. Therefore, clean
+ * up, handle the fault and retry from the
+ * beginning.
+ */
+ queue_unlock(hb);
+
+ /*
+ * Keys 0..(i-1) are implicitly put
+ * on unqueue_multiple.
+ */
+ put_futex_key(&q->key);
+
+ *awaken = unqueue_multiple(qs, i);
+
+ __set_current_state(TASK_RUNNING);
+
+ /*
+ * On a real fault, prioritize the error even if
+ * some other futex was awoken. Userspace gave
+ * us a bad address, -EFAULT them.
+ */
+ ret = get_user(uval, q->uaddr);
+ if (ret)
+ return ret;
+
+ /*
+ * Even if the page fault was handled, If
+ * something was already awaken, we can safely
+ * give up and succeed to give a hint for userspace to
+ * acquire the right futex faster.
+ */
+ if (*awaken >= 0)
+ return 1;
+
+ goto retry;
+ }
+
+ if (uval != q->uval) {
+ queue_unlock(hb);
+
+ put_futex_key(&qs[i].key);
+
+ /*
+ * If something was already awaken, we can
+ * safely ignore the error and succeed.
+ */
+ *awaken = unqueue_multiple(qs, i);
+ __set_current_state(TASK_RUNNING);
+ if (*awaken >= 0)
+ return 1;
+
+ return -EWOULDBLOCK;
+ }
+
+ /*
+ * The bucket lock can't be held while dealing with the
+ * next futex. Queue each futex at this moment so hb can
+ * be unlocked.
+ */
+ queue_me(&qs[i], hb);
+ }
+ return 0;
+}
+
+/**
+ * futex_wait_multiple() - Prepare to wait on and enqueue several futexes
+ * @qs: The list of futexes to wait on
+ * @op: Operation code from futex's syscall
+ * @count: The number of objects
+ * @abs_time: Timeout before giving up and returning to userspace
+ *
+ * Entry point for the FUTEX_WAIT_MULTIPLE futex operation, this function
+ * sleeps on a group of futexes and returns on the first futex that
+ * triggered, or after the timeout has elapsed.
+ *
+ * Return:
+ * - >=0 - Hint to the futex that was awoken
+ * - <0 - On error
+ */
+static int futex_wait_multiple(struct futex_q *qs, int op,
+ u32 count, ktime_t *abs_time)
+{
+ struct hrtimer_sleeper timeout, *to;
+ int ret, flags = 0, hint = 0;
+ unsigned int i;
+
+ if (!(op & FUTEX_PRIVATE_FLAG))
+ flags |= FLAGS_SHARED;
+
+ if (op & FUTEX_CLOCK_REALTIME)
+ flags |= FLAGS_CLOCKRT;
+
+ to = futex_setup_timer(abs_time, &timeout, flags, 0);
+ while (1) {
+ ret = futex_wait_multiple_setup(qs, count, flags, &hint);
+ if (ret) {
+ if (ret > 0) {
+ /* A futex was awaken during setup */
+ ret = hint;
+ }
+ break;
+ }
+
+ if (to)
+ hrtimer_start_expires(&to->timer, HRTIMER_MODE_ABS);
+
+ /*
+ * Avoid sleeping if another thread already tried to
+ * wake us.
+ */
+ for (i = 0; i < count; i++) {
+ if (plist_node_empty(&qs[i].list))
+ break;
+ }
+
+ if (i == count && (!to || to->task))
+ freezable_schedule();
+
+ ret = unqueue_multiple(qs, count);
+
+ __set_current_state(TASK_RUNNING);
+
+ if (ret >= 0)
+ break;
+ if (to && !to->task) {
+ ret = -ETIMEDOUT;
+ break;
+ } else if (signal_pending(current)) {
+ ret = -ERESTARTSYS;
+ break;
+ }
+ /*
+ * The final case is a spurious wakeup, for
+ * which just retry.
+ */
+ }
+
+ if (to) {
+ hrtimer_cancel(&to->timer);
+ destroy_hrtimer_on_stack(&to->timer);
+ }
+
+ return ret;
+}
+
static int futex_wait(u32 __user *uaddr, unsigned int flags, u32 val,
ktime_t *abs_time, u32 bitset)
{
@@ -3907,6 +4139,43 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,
return -ENOSYS;
}
+/**
+ * futex_read_wait_block - Read an array of futex_wait_block from userspace
+ * @uaddr: Userspace address of the block
+ * @count: Number of blocks to be read
+ *
+ * This function creates and allocate an array of futex_q (we zero it to
+ * initialize the fields) and then, for each futex_wait_block element from
+ * userspace, fill a futex_q element with proper values.
+ */
+inline struct futex_q *futex_read_wait_block(u32 __user *uaddr, u32 count)
+{
+ unsigned int i;
+ struct futex_q *qs;
+ struct futex_wait_block fwb;
+ struct futex_wait_block __user *entry =
+ (struct futex_wait_block __user *)uaddr;
+
+ if (!count || count > FUTEX_MULTIPLE_MAX_COUNT)
+ return ERR_PTR(-EINVAL);
+
+ qs = kcalloc(count, sizeof(*qs), GFP_KERNEL);
+ if (!qs)
+ return ERR_PTR(-ENOMEM);
+
+ for (i = 0; i < count; i++) {
+ if (copy_from_user(&fwb, &entry[i], sizeof(fwb))) {
+ kfree(qs);
+ return ERR_PTR(-EFAULT);
+ }
+
+ qs[i].uaddr = fwb.uaddr;
+ qs[i].uval = fwb.val;
+ qs[i].bitset = fwb.bitset;
+ }
+
+ return qs;
+}
SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
struct __kernel_timespec __user *, utime, u32 __user *, uaddr2,
@@ -3919,7 +4188,8 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI ||
cmd == FUTEX_WAIT_BITSET ||
- cmd == FUTEX_WAIT_REQUEUE_PI)) {
+ cmd == FUTEX_WAIT_REQUEUE_PI ||
+ cmd == FUTEX_WAIT_MULTIPLE)) {
if (unlikely(should_fail_futex(!(op & FUTEX_PRIVATE_FLAG))))
return -EFAULT;
if (get_timespec64(&ts, utime))
@@ -3940,6 +4210,25 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
cmd == FUTEX_CMP_REQUEUE_PI || cmd == FUTEX_WAKE_OP)
val2 = (u32) (unsigned long) utime;
+ if (cmd == FUTEX_WAIT_MULTIPLE) {
+ int ret;
+ struct futex_q *qs;
+
+#ifdef CONFIG_X86_X32
+ if (unlikely(in_x32_syscall()))
+ return -ENOSYS;
+#endif
+ qs = futex_read_wait_block(uaddr, val);
+
+ if (IS_ERR(qs))
+ return PTR_ERR(qs);
+
+ ret = futex_wait_multiple(qs, op, val, tp);
+ kfree(qs);
+
+ return ret;
+ }
+
return do_futex(uaddr, op, val, tp, uaddr2, val2, val3);
}
@@ -4102,6 +4391,57 @@ COMPAT_SYSCALL_DEFINE3(get_robust_list, int, pid,
#endif /* CONFIG_COMPAT */
#ifdef CONFIG_COMPAT_32BIT_TIME
+/**
+ * struct compat_futex_wait_block - Block of futexes to be waited for
+ * @uaddr: User address of the futex (compatible pointer)
+ * @val: Futex value expected by userspace
+ * @bitset: Bitset for the optional bitmasked wakeup
+ */
+struct compat_futex_wait_block {
+ compat_uptr_t uaddr;
+ __u32 val;
+ __u32 bitset;
+};
+
+/**
+ * compat_futex_read_wait_block - Read an array of futex_wait_block from
+ * userspace
+ * @uaddr: Userspace address of the block
+ * @count: Number of blocks to be read
+ *
+ * This function does the same as futex_read_wait_block(), except that it
+ * converts the pointer to the futex from the compat version to the regular one.
+ */
+inline struct futex_q *compat_futex_read_wait_block(u32 __user *uaddr,
+ u32 count)
+{
+ unsigned int i;
+ struct futex_q *qs;
+ struct compat_futex_wait_block fwb;
+ struct compat_futex_wait_block __user *entry =
+ (struct compat_futex_wait_block __user *)uaddr;
+
+ if (!count || count > FUTEX_MULTIPLE_MAX_COUNT)
+ return ERR_PTR(-EINVAL);
+
+ qs = kcalloc(count, sizeof(*qs), GFP_KERNEL);
+ if (!qs)
+ return ERR_PTR(-ENOMEM);
+
+ for (i = 0; i < count; i++) {
+ if (copy_from_user(&fwb, &entry[i], sizeof(fwb))) {
+ kfree(qs);
+ return ERR_PTR(-EFAULT);
+ }
+
+ qs[i].uaddr = compat_ptr(fwb.uaddr);
+ qs[i].uval = fwb.val;
+ qs[i].bitset = fwb.bitset;
+ }
+
+ return qs;
+}
+
SYSCALL_DEFINE6(futex_time32, u32 __user *, uaddr, int, op, u32, val,
struct old_timespec32 __user *, utime, u32 __user *, uaddr2,
u32, val3)
@@ -4113,7 +4453,8 @@ SYSCALL_DEFINE6(futex_time32, u32 __user *, uaddr, int, op, u32, val,
if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI ||
cmd == FUTEX_WAIT_BITSET ||
- cmd == FUTEX_WAIT_REQUEUE_PI)) {
+ cmd == FUTEX_WAIT_REQUEUE_PI ||
+ cmd == FUTEX_WAIT_MULTIPLE)) {
if (get_old_timespec32(&ts, utime))
return -EFAULT;
if (!timespec64_valid(&ts))
@@ -4128,6 +4469,19 @@ SYSCALL_DEFINE6(futex_time32, u32 __user *, uaddr, int, op, u32, val,
cmd == FUTEX_CMP_REQUEUE_PI || cmd == FUTEX_WAKE_OP)
val2 = (int) (unsigned long) utime;
+ if (cmd == FUTEX_WAIT_MULTIPLE) {
+ int ret;
+ struct futex_q *qs = compat_futex_read_wait_block(uaddr, val);
+
+ if (IS_ERR(qs))
+ return PTR_ERR(qs);
+
+ ret = futex_wait_multiple(qs, op, val, tp);
+ kfree(qs);
+
+ return ret;
+ }
+
return do_futex(uaddr, op, val, tp, uaddr2, val2, val3);
}
#endif /* CONFIG_COMPAT_32BIT_TIME */
diff --git a/tools/testing/selftests/futex/functional/futex_wait_timeout.c b/tools/testing/selftests/futex/functional/futex_wait_timeout.c
index ee55e6d389a3f053194435342c4e471dc7cf8786..2a63e1c2cfb6407a5988233217cff2e52787bc66 100644
--- a/tools/testing/selftests/futex/functional/futex_wait_timeout.c
+++ b/tools/testing/selftests/futex/functional/futex_wait_timeout.c
@@ -11,6 +11,7 @@
*
* HISTORY
* 2009-Nov-6: Initial version by Darren Hart <dvhart@linux.intel.com>
+ * 2019-Dec-13: Add WAIT_MULTIPLE test by Krisman <krisman@collabora.com>
*
*****************************************************************************/
@@ -41,6 +42,8 @@ int main(int argc, char *argv[])
{
futex_t f1 = FUTEX_INITIALIZER;
struct timespec to;
+ time_t secs;
+ struct futex_wait_block fwb = {&f1, f1, 0};
int res, ret = RET_PASS;
int c;
@@ -65,7 +68,7 @@ int main(int argc, char *argv[])
}
ksft_print_header();
- ksft_set_plan(1);
+ ksft_set_plan(2);
ksft_print_msg("%s: Block on a futex and wait for timeout\n",
basename(argv[0]));
ksft_print_msg("\tArguments: timeout=%ldns\n", timeout_ns);
@@ -79,8 +82,39 @@ int main(int argc, char *argv[])
if (!res || errno != ETIMEDOUT) {
fail("futex_wait returned %d\n", ret < 0 ? errno : ret);
ret = RET_FAIL;
+ } else
+ ksft_test_result_pass("futex_wait timeout succeeds\n");
+
+ info("Calling futex_wait_multiple on f1: %u @ %p\n", f1, &f1);
+
+ /* Setup absolute time */
+ ret = clock_gettime(CLOCK_REALTIME, &to);
+ secs = (to.tv_nsec + timeout_ns) / 1000000000;
+ to.tv_nsec = ((int64_t)to.tv_nsec + timeout_ns) % 1000000000;
+ to.tv_sec += secs;
+ info("to.tv_sec = %ld\n", to.tv_sec);
+ info("to.tv_nsec = %ld\n", to.tv_nsec);
+
+ res = futex_wait_multiple(&fwb, 1, &to,
+ FUTEX_PRIVATE_FLAG | FUTEX_CLOCK_REALTIME);
+
+#ifdef __ILP32__
+ if (res == -1 && errno == ENOSYS) {
+ ksft_test_result_skip("futex_wait_multiple not supported at x32\n");
+ } else {
+ ksft_test_result_fail("futex_wait_multiple returned %d\n",
+ res < 0 ? errno : res);
+ ret = RET_FAIL;
}
+#else
+ if (!res || errno != ETIMEDOUT) {
+ ksft_test_result_fail("futex_wait_multiple returned %d\n",
+ res < 0 ? errno : res);
+ ret = RET_FAIL;
+ } else
+ ksft_test_result_pass("futex_wait_multiple timeout succeeds\n");
+#endif /* __ILP32__ */
- print_result(TEST_NAME, ret);
+ ksft_print_cnts();
return ret;
}
diff --git a/tools/testing/selftests/futex/include/futextest.h b/tools/testing/selftests/futex/include/futextest.h
index ddbcfc9b7bac4aebb5bac2f249e26ecfd948aa84..bb103bef4557012ef9a389ca74c868e4476a8a31 100644
--- a/tools/testing/selftests/futex/include/futextest.h
+++ b/tools/testing/selftests/futex/include/futextest.h
@@ -38,6 +38,14 @@ typedef volatile u_int32_t futex_t;
#ifndef FUTEX_CMP_REQUEUE_PI
#define FUTEX_CMP_REQUEUE_PI 12
#endif
+#ifndef FUTEX_WAIT_MULTIPLE
+#define FUTEX_WAIT_MULTIPLE 13
+struct futex_wait_block {
+ futex_t *uaddr;
+ futex_t val;
+ __u32 bitset;
+};
+#endif
#ifndef FUTEX_WAIT_REQUEUE_PI_PRIVATE
#define FUTEX_WAIT_REQUEUE_PI_PRIVATE (FUTEX_WAIT_REQUEUE_PI | \
FUTEX_PRIVATE_FLAG)
@@ -80,6 +88,20 @@ futex_wait(futex_t *uaddr, futex_t val, struct timespec *timeout, int opflags)
return futex(uaddr, FUTEX_WAIT, val, timeout, NULL, 0, opflags);
}
+/**
+ * futex_wait_multiple() - block on several futexes with optional timeout
+ * @fwb: wait block user space address
+ * @count: number of entities at fwb
+ * @timeout: absolute timeout
+ */
+static inline int
+futex_wait_multiple(struct futex_wait_block *fwb, int count,
+ struct timespec *timeout, int opflags)
+{
+ return futex(fwb, FUTEX_WAIT_MULTIPLE, count, timeout, NULL, 0,
+ opflags);
+}
+
/**
* futex_wake() - wake one or more tasks blocked on uaddr
* @nr_wake: wake up to this many tasks
diff --git a/tools/testing/selftests/futex/functional/futex_wait_wouldblock.c b/tools/testing/selftests/futex/functional/futex_wait_wouldblock.c
index 0ae390ff816449c88d0bb655a26eb014382c2b4f..bcbac042992d447e0bc9ef5fefe94e875de310f2 100644
--- a/tools/testing/selftests/futex/functional/futex_wait_wouldblock.c
+++ b/tools/testing/selftests/futex/functional/futex_wait_wouldblock.c
@@ -12,6 +12,7 @@
*
* HISTORY
* 2009-Nov-14: Initial version by Gowrishankar <gowrishankar.m@in.ibm.com>
+ * 2019-Dec-13: Add WAIT_MULTIPLE test by Krisman <krisman@collabora.com>
*
*****************************************************************************/
@@ -40,6 +41,7 @@ int main(int argc, char *argv[])
{
struct timespec to = {.tv_sec = 0, .tv_nsec = timeout_ns};
futex_t f1 = FUTEX_INITIALIZER;
+ struct futex_wait_block fwb = {&f1, f1+1, 0};
int res, ret = RET_PASS;
int c;
@@ -61,7 +63,7 @@ int main(int argc, char *argv[])
}
ksft_print_header();
- ksft_set_plan(1);
+ ksft_set_plan(2);
ksft_print_msg("%s: Test the unexpected futex value in FUTEX_WAIT\n",
basename(argv[0]));
@@ -71,8 +73,30 @@ int main(int argc, char *argv[])
fail("futex_wait returned: %d %s\n",
res ? errno : res, res ? strerror(errno) : "");
ret = RET_FAIL;
+ } else
+ ksft_test_result_pass("futex_wait wouldblock succeeds\n");
+
+ info("Calling futex_wait_multiple on f1: %u @ %p with val=%u\n",
+ f1, &f1, f1+1);
+ res = futex_wait_multiple(&fwb, 1, NULL, FUTEX_PRIVATE_FLAG);
+
+#ifdef __ILP32__
+ if (res != -1 || errno != ENOSYS) {
+ ksft_test_result_fail("futex_wait_multiple returned %d\n",
+ res < 0 ? errno : res);
+ ret = RET_FAIL;
+ } else {
+ ksft_test_result_skip("futex_wait_multiple not supported at x32\n");
+ }
+#else
+ if (!res || errno != EWOULDBLOCK) {
+ ksft_test_result_fail("futex_wait_multiple returned %d\n",
+ res < 0 ? errno : res);
+ ret = RET_FAIL;
}
+ ksft_test_result_pass("futex_wait_multiple wouldblock succeeds\n");
+#endif /* __ILP32__ */
- print_result(TEST_NAME, ret);
+ ksft_print_cnts();
return ret;
}
diff --git a/tools/testing/selftests/futex/functional/.gitignore b/tools/testing/selftests/futex/functional/.gitignore
index a09f570619023750f558c84004aff166b4337d72..4660128a545edb04a17cc6bd9760931c1386122f 100644
--- a/tools/testing/selftests/futex/functional/.gitignore
+++ b/tools/testing/selftests/futex/functional/.gitignore
@@ -5,3 +5,4 @@ futex_wait_private_mapped_file
futex_wait_timeout
futex_wait_uninitialized_heap
futex_wait_wouldblock
+futex_wait_multiple
diff --git a/tools/testing/selftests/futex/functional/Makefile b/tools/testing/selftests/futex/functional/Makefile
index 30996306cabcfe89a47977643e529b122893bb7e..75f9fface11fa3c90c1bdb9a49b3ea51291afd58 100644
--- a/tools/testing/selftests/futex/functional/Makefile
+++ b/tools/testing/selftests/futex/functional/Makefile
@@ -14,7 +14,8 @@ TEST_GEN_FILES := \
futex_requeue_pi_signal_restart \
futex_requeue_pi_mismatched_ops \
futex_wait_uninitialized_heap \
- futex_wait_private_mapped_file
+ futex_wait_private_mapped_file \
+ futex_wait_multiple
TEST_PROGS := run.sh
diff --git a/tools/testing/selftests/futex/functional/futex_wait_multiple.c b/tools/testing/selftests/futex/functional/futex_wait_multiple.c
new file mode 100644
index 0000000000000000000000000000000000000000..b48422e79f42edba1653bb0bd2a4c4fd98d2d48d
--- /dev/null
+++ b/tools/testing/selftests/futex/functional/futex_wait_multiple.c
@@ -0,0 +1,173 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/******************************************************************************
+ *
+ * Copyright © Collabora, Ltd., 2019
+ *
+ * DESCRIPTION
+ * Test basic semantics of FUTEX_WAIT_MULTIPLE
+ *
+ * AUTHOR
+ * Gabriel Krisman Bertazi <krisman@collabora.com>
+ *
+ * HISTORY
+ * 2019-Dec-13: Initial version by Krisman <krisman@collabora.com>
+ *
+ *****************************************************************************/
+
+#include <errno.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <pthread.h>
+#include "futextest.h"
+#include "logging.h"
+
+#define TEST_NAME "futex-wait-multiple"
+#define timeout_ns 100000
+#define MAX_COUNT 128
+#define WAKE_WAIT_US 3000000
+
+int ret = RET_PASS;
+char *progname;
+futex_t f[MAX_COUNT] = {0};
+struct futex_wait_block fwb[MAX_COUNT];
+
+void usage(char *prog)
+{
+ printf("Usage: %s\n", prog);
+ printf(" -c Use color\n");
+ printf(" -h Display this help message\n");
+ printf(" -v L Verbosity level: %d=QUIET %d=CRITICAL %d=INFO\n",
+ VQUIET, VCRITICAL, VINFO);
+}
+
+void test_count_overflow(void)
+{
+ futex_t f = FUTEX_INITIALIZER;
+ struct futex_wait_block fwb[MAX_COUNT+1];
+ int res, i;
+
+ ksft_print_msg("%s: Test a too big number of futexes\n", progname);
+
+ for (i = 0; i < MAX_COUNT+1; i++) {
+ fwb[i].uaddr = &f;
+ fwb[i].val = f;
+ fwb[i].bitset = 0;
+ }
+
+ res = futex_wait_multiple(fwb, MAX_COUNT+1, NULL, FUTEX_PRIVATE_FLAG);
+
+#ifdef __ILP32__
+ if (res != -1 || errno != ENOSYS) {
+ ksft_test_result_fail("futex_wait_multiple returned %d\n",
+ res < 0 ? errno : res);
+ ret = RET_FAIL;
+ } else {
+ ksft_test_result_skip("futex_wait_multiple not supported at x32\n");
+ }
+#else
+ if (res != -1 || errno != EINVAL) {
+ ksft_test_result_fail("futex_wait_multiple returned %d\n",
+ res < 0 ? errno : res);
+ ret = RET_FAIL;
+ } else {
+ ksft_test_result_pass("futex_wait_multiple count overflow succeed\n");
+ }
+
+#endif /* __ILP32__ */
+}
+
+void *waiterfn(void *arg)
+{
+ int res;
+
+ res = futex_wait_multiple(fwb, MAX_COUNT, NULL, FUTEX_PRIVATE_FLAG);
+
+#ifdef __ILP32__
+ if (res != -1 || errno != ENOSYS) {
+ ksft_test_result_fail("futex_wait_multiple returned %d\n",
+ res < 0 ? errno : res);
+ ret = RET_FAIL;
+ } else {
+ ksft_test_result_skip("futex_wait_multiple not supported at x32\n");
+ }
+#else
+ if (res < 0)
+ ksft_print_msg("waiter failed %d\n", res);
+
+ info("futex_wait_multiple: Got hint futex %d was freed\n", res);
+#endif /* __ILP32__ */
+
+ return NULL;
+}
+
+void test_fwb_wakeup(void)
+{
+ int res, i;
+ pthread_t waiter;
+
+ ksft_print_msg("%s: Test wake up in a list of futex\n", progname);
+
+ for (i = 0; i < MAX_COUNT; i++) {
+ fwb[i].uaddr = &f[i];
+ fwb[i].val = f[i];
+ fwb[i].bitset = 0xffffffff;
+ }
+
+ res = pthread_create(&waiter, NULL, waiterfn, NULL);
+ if (res) {
+ ksft_test_result_fail("Creating waiting thread failed");
+ ksft_exit_fail();
+ }
+
+ usleep(WAKE_WAIT_US);
+ res = futex_wake(&(f[MAX_COUNT-1]), 1, FUTEX_PRIVATE_FLAG);
+ if (res != 1) {
+ ksft_test_result_fail("Failed to wake thread res=%d\n", res);
+ ksft_exit_fail();
+ }
+
+ pthread_join(waiter, NULL);
+ ksft_test_result_pass("%s succeed\n", __func__);
+}
+
+int main(int argc, char *argv[])
+{
+ int c;
+
+ while ((c = getopt(argc, argv, "cht:v:")) != -1) {
+ switch (c) {
+ case 'c':
+ log_color(1);
+ break;
+ case 'h':
+ usage(basename(argv[0]));
+ exit(0);
+ case 'v':
+ log_verbosity(atoi(optarg));
+ break;
+ default:
+ usage(basename(argv[0]));
+ exit(1);
+ }
+ }
+
+ progname = basename(argv[0]);
+
+ ksft_print_header();
+ ksft_set_plan(2);
+
+ test_count_overflow();
+
+#ifdef __ILP32__
+ // if it's a 32x binary, there's no futex to wakeup
+ ksft_test_result_skip("futex_wait_multiple not supported at x32\n");
+#else
+ test_fwb_wakeup();
+#endif /* __ILP32__ */
+
+ ksft_print_cnts();
+ return ret;
+}
diff --git a/tools/testing/selftests/futex/functional/run.sh b/tools/testing/selftests/futex/functional/run.sh
index 1acb6ace1680e8f3d6b3ee2dc528c19ddfdb018e..a8be94f28ff78b4879d2d19bca5d9b0fcb26c1f8 100755
--- a/tools/testing/selftests/futex/functional/run.sh
+++ b/tools/testing/selftests/futex/functional/run.sh
@@ -73,3 +73,6 @@ echo
echo
./futex_wait_uninitialized_heap $COLOR
./futex_wait_private_mapped_file $COLOR
+
+echo
+./futex_wait_multiple $COLOR
diff --git a/include/uapi/linux/futex.h b/include/uapi/linux/futex.h
index 580001e89c6caed57dd8b3cb491d65dce846caff..a3e760886b8e7e74285fdcf2caaaa6f66ad16675 100644
--- a/include/uapi/linux/futex.h
+++ b/include/uapi/linux/futex.h
@@ -21,7 +21,7 @@
#define FUTEX_WAKE_BITSET 10
#define FUTEX_WAIT_REQUEUE_PI 11
#define FUTEX_CMP_REQUEUE_PI 12
-#define FUTEX_WAIT_MULTIPLE 13
+#define FUTEX_WAIT_MULTIPLE 31
#define FUTEX_PRIVATE_FLAG 128
#define FUTEX_CLOCK_REALTIME 256
diff --git a/kernel/futex.c b/kernel/futex.c
index 58cf9eb2b851b4858e29b5ef4114a29a92e676ba..e0bb628a5e1988dcc9ae5442a4259edc229d578d 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -4198,7 +4198,7 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
return -EINVAL;
t = timespec64_to_ktime(ts);
- if (cmd == FUTEX_WAIT)
+ if (cmd == FUTEX_WAIT || cmd == FUTEX_WAIT_MULTIPLE)
t = ktime_add_safe(ktime_get(), t);
tp = &t;
}
@@ -4399,6 +4399,7 @@ COMPAT_SYSCALL_DEFINE3(get_robust_list, int, pid,
*/
struct compat_futex_wait_block {
compat_uptr_t uaddr;
+ __u32 pad;
__u32 val;
__u32 bitset;
};
@@ -4461,7 +4462,7 @@ SYSCALL_DEFINE6(futex_time32, u32 __user *, uaddr, int, op, u32, val,
return -EINVAL;
t = timespec64_to_ktime(ts);
- if (cmd == FUTEX_WAIT)
+ if (cmd == FUTEX_WAIT || cmd == FUTEX_WAIT_MULTIPLE)
t = ktime_add_safe(ktime_get(), t);
tp = &t;
}
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