[tip: locking/core] futex: Set task::futex_state to DEAD right after handling futex exit

[tip-bot2 for Thomas Gleixner]

The following commit has been merged into the locking/core branch of tip:

Commit-ID:     f24f22435dcc11389acc87e5586239c1819d217c
Gitweb:        https://git.kernel.org/tip/f24f22435dcc11389acc87e5586239c1819d217c
Author:        Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate:    Wed, 06 Nov 2019 22:55:40 +01:00
Committer:     Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Wed, 20 Nov 2019 09:40:08 +01:00

futex: Set task::futex_state to DEAD right after handling futex exit

Setting task::futex_state in do_exit() is rather arbitrarily placed for no
reason. Move it into the futex code.

Note, this is only done for the exit cleanup as the exec cleanup cannot set
the state to FUTEX_STATE_DEAD because the task struct is still in active
use.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Ingo Molnar <mingo@xxxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20191106224556.439511191@xxxxxxxxxxxxx


---
 kernel/exit.c  | 1 -
 kernel/futex.c | 1 +
 2 files changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/exit.c b/kernel/exit.c
index cd893b5..f3b8fa1 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -837,7 +837,6 @@ void __noreturn do_exit(long code)
 	 * Make sure we are holding no locks:
 	 */
 	debug_check_no_locks_held();
-	futex_exit_done(tsk);
 
 	if (tsk->io_context)
 		exit_io_context(tsk);
diff --git a/kernel/futex.c b/kernel/futex.c
index 909e4d3..426dd71 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -3682,6 +3682,7 @@ void futex_exec_release(struct task_struct *tsk)
 void futex_exit_release(struct task_struct *tsk)
 {
 	futex_exec_release(tsk);
+	futex_exit_done(tsk);
 }
 
 long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,