From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753444AbeE3LUm (ORCPT ); Wed, 30 May 2018 07:20:42 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:60990 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751209AbeE3LHH (ORCPT ); Wed, 30 May 2018 07:07:07 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Dmitry Torokhov" , "Zhang Bo" Date: Wed, 30 May 2018 11:52:41 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 082/153] Input: matrix_keypad - fix race when disabling interrupts In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.102-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Zhang Bo commit ea4f7bd2aca9f68470e9aac0fc9432fd180b1fe7 upstream. If matrix_keypad_stop() is executing and the keypad interrupt is triggered, disable_row_irqs() may be called by both matrix_keypad_interrupt() and matrix_keypad_stop() at the same time, causing interrupts to be disabled twice and the keypad being "stuck" after resuming. Take lock when setting keypad->stopped to ensure that ISR will not race with matrix_keypad_stop() disabling interrupts. Signed-off-by: Zhang Bo Signed-off-by: Dmitry Torokhov Signed-off-by: Ben Hutchings --- drivers/input/keyboard/matrix_keypad.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/input/keyboard/matrix_keypad.c +++ b/drivers/input/keyboard/matrix_keypad.c @@ -214,8 +214,10 @@ static void matrix_keypad_stop(struct in { struct matrix_keypad *keypad = input_get_drvdata(dev); + spin_lock_irq(&keypad->lock); keypad->stopped = true; - mb(); + spin_unlock_irq(&keypad->lock); + flush_work(&keypad->work.work); /* * matrix_keypad_scan() will leave IRQs enabled;