Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     linux-kernel@vger.kernel.org
Cc:     tglx@linutronix.de, Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@kernel.org>,
        Anna-Maria Gleixner <anna-maria@linutronix.de>,
        Andrew Morton <akpm@linux-foundation.org>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Subject: [PATCH 6/6] userns: Use irqsave variant of refcount_dec_and_lock()
Date:   Tue,  3 Jul 2018 22:01:41 +0200
Message-Id: <20180703200141.28415-7-bigeasy@linutronix.de>
In-Reply-To: <20180703200141.28415-1-bigeasy@linutronix.de>
References: <20180703200141.28415-1-bigeasy@linutronix.de>
MIME-Version: 1.0
Content-Transfer-Encoding: quoted-printable
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

From: Anna-Maria Gleixner <anna-maria@linutronix.de>

The irqsave variant of refcount_dec_and_lock handles irqsave/restore when
taking/releasing the spin lock. With this variant the call of
local_irq_save/restore is no longer required.

Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
[bigeasy: s@atomic_dec_and_lock@refcount_dec_and_lock@g ]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 kernel/user.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/kernel/user.c b/kernel/user.c
index 5f65ef195259..0df9b1640b2a 100644
--- a/kernel/user.c
+++ b/kernel/user.c
@@ -169,11 +169,8 @@ void free_uid(struct user_struct *up)
 	if (!up)
 		return;
=20
-	local_irq_save(flags);
-	if (refcount_dec_and_lock(&up->__count, &uidhash_lock))
+	if (refcount_dec_and_lock_irqsave(&up->__count, &uidhash_lock, &flags))
 		free_user(up, flags);
-	else
-		local_irq_restore(flags);
 }
=20
 struct user_struct *alloc_uid(kuid_t uid)
--=20
2.18.0