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authorMichael Bestas <mkbestas@lineageos.org>2021-03-17 21:27:13 +0200
committerMichael Bestas <mkbestas@lineageos.org>2021-03-17 21:27:13 +0200
commit183f2051d299eb7b35d8e37d01be9077dd809839 (patch)
tree4937226d67edb7c827ce7a360d1f83ff07dd36e9 /kernel/futex.c
parentc66c1e4925165243b33081fd609c4a8a7d35e2fc (diff)
parent58bc8e0469d0808754b42e423934da639c07b6ba (diff)
Merge branch 'android-4.4-p' of https://android.googlesource.com/kernel/common into lineage-18.1-caf-msm8998
This brings LA.UM.9.2.r1-02700-SDMxx0.0 up to date with https://android.googlesource.com/kernel/common/ android-4.4-p at commit: 58bc8e0469d08 Merge 4.4.261 into android-4.4-p Conflicts: drivers/block/zram/zram_drv.c drivers/block/zram/zram_drv.h mm/zsmalloc.c Change-Id: I451bffa685eaaea04938bc6d0b8e3f4bb0f869e9
Diffstat (limited to 'kernel/futex.c')
-rw-r--r--kernel/futex.c35
1 files changed, 18 insertions, 17 deletions
diff --git a/kernel/futex.c b/kernel/futex.c
index dcc7d0e9138f..cb96565ad7c0 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -874,7 +874,9 @@ static void free_pi_state(struct futex_pi_state *pi_state)
* and has cleaned up the pi_state already
*/
if (pi_state->owner) {
+ raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock);
pi_state_update_owner(pi_state, NULL);
+ raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
rt_mutex_proxy_unlock(&pi_state->pi_mutex);
}
@@ -1406,7 +1408,7 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this,
if (pi_state->owner != current)
return -EINVAL;
- raw_spin_lock(&pi_state->pi_mutex.wait_lock);
+ raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock);
new_owner = rt_mutex_next_owner(&pi_state->pi_mutex);
/*
@@ -2248,10 +2250,6 @@ static int __fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
oldowner = pi_state->owner;
- /* Owner died? */
- if (!pi_state->owner)
- newtid |= FUTEX_OWNER_DIED;
-
/*
* We are here because either:
*
@@ -2287,7 +2285,7 @@ retry:
}
if (__rt_mutex_futex_trylock(&pi_state->pi_mutex)) {
- /* We got the lock after all, nothing to fix. */
+ /* We got the lock. pi_state is correct. Tell caller */
return 1;
}
@@ -2309,6 +2307,9 @@ retry:
}
newtid = task_pid_vnr(newowner) | FUTEX_WAITERS;
+ /* Owner died? */
+ if (!pi_state->owner)
+ newtid |= FUTEX_OWNER_DIED;
if (get_futex_value_locked(&uval, uaddr))
goto handle_fault;
@@ -2329,7 +2330,7 @@ retry:
*/
pi_state_update_owner(pi_state, newowner);
- return 0;
+ return argowner == current;
/*
* To handle the page fault we need to drop the hash bucket
@@ -2412,8 +2413,6 @@ static long futex_wait_restart(struct restart_block *restart);
*/
static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
{
- int ret = 0;
-
if (locked) {
/*
* Got the lock. We might not be the anticipated owner if we
@@ -2424,8 +2423,8 @@ static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
* stable state, anything else needs more attention.
*/
if (q->pi_state->owner != current)
- ret = fixup_pi_state_owner(uaddr, q, current);
- goto out;
+ return fixup_pi_state_owner(uaddr, q, current);
+ return 1;
}
/*
@@ -2436,10 +2435,8 @@ static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
* Another speculative read; pi_state->owner == current is unstable
* but needs our attention.
*/
- if (q->pi_state->owner == current) {
- ret = fixup_pi_state_owner(uaddr, q, NULL);
- goto out;
- }
+ if (q->pi_state->owner == current)
+ return fixup_pi_state_owner(uaddr, q, NULL);
/*
* Paranoia check. If we did not take the lock, then we should not be
@@ -2448,8 +2445,7 @@ static int fixup_owner(u32 __user *uaddr, struct futex_q *q, int locked)
if (WARN_ON_ONCE(rt_mutex_owner(&q->pi_state->pi_mutex) == current))
return fixup_pi_state_owner(uaddr, q, current);
-out:
- return ret ? ret : locked;
+ return 0;
}
/**
@@ -3071,6 +3067,11 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
*/
free_pi_state(q.pi_state);
spin_unlock(q.lock_ptr);
+ /*
+ * Adjust the return value. It's either -EFAULT or
+ * success (1) but the caller expects 0 for success.
+ */
+ ret = ret < 0 ? ret : 0;
}
} else {
struct rt_mutex *pi_mutex;