From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 93F85C433E1 for ; Tue, 4 Aug 2020 09:18:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A023C206DA for ; Tue, 4 Aug 2020 09:18:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729596AbgHDJSR (ORCPT ); Tue, 4 Aug 2020 05:18:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37706 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725904AbgHDJSQ (ORCPT ); Tue, 4 Aug 2020 05:18:16 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 26D9FC06174A for ; Tue, 4 Aug 2020 02:18:16 -0700 (PDT) Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1k2t5I-0001VS-UG; Tue, 04 Aug 2020 11:18:12 +0200 Received: from afa by dude.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1k2t5I-00036w-67; Tue, 04 Aug 2020 11:18:12 +0200 From: Ahmad Fatoum To: Thorsten Scherer , =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= , Pengutronix Kernel Team , Linus Walleij , Bartosz Golaszewski Cc: Ahmad Fatoum , linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] gpio: siox: indicate exclusive support of threaded IRQs Date: Tue, 4 Aug 2020 11:16:03 +0200 Message-Id: <20200804091603.541-1-a.fatoum@pengutronix.de> X-Mailer: git-send-email 2.28.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: afa@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-gpio@vger.kernel.org Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org Generic GPIO consumers like gpio-keys use request_any_context_irq() to request a threaded handler if irq_settings_is_nested_thread() == true or a hardirq handler otherwise. Drivers using handle_nested_irq() must be sure that the nested IRQs were requested with threaded handlers, because the IRQ is handled by calling action->thread_fn(). The gpio-siox driver dispatches IRQs via handle_nested_irq, but has irq_settings_is_nested_thread() == false. Set gpio_irq_chip::threaded to remedy this. Signed-off-by: Ahmad Fatoum --- I am writing a driver similar to gpio-siox and I ran into a null pointer dereference, because ->threaded wasn't set. I didn't test this on actual SIOX hardware. This patch doesn't fix the case were are driver explicitly calls request_irq and is combined with a driver that does handle_nested_irq. Is there a flag, such drivers should additionally set or should we check action->thread_fn before calling it inside handle_nested_irq? --- drivers/gpio/gpio-siox.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpio/gpio-siox.c b/drivers/gpio/gpio-siox.c index 26e1fe092304..f8c5e9fc4bac 100644 --- a/drivers/gpio/gpio-siox.c +++ b/drivers/gpio/gpio-siox.c @@ -245,6 +245,7 @@ static int gpio_siox_probe(struct siox_device *sdevice) girq->chip = &ddata->ichip; girq->default_type = IRQ_TYPE_NONE; girq->handler = handle_level_irq; + girq->threaded = true; ret = devm_gpiochip_add_data(dev, &ddata->gchip, NULL); if (ret) -- 2.28.0