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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AE010C433F5 for ; Sun, 23 Jan 2022 14:22:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233494AbiAWOWk (ORCPT ); Sun, 23 Jan 2022 09:22:40 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:36762 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232277AbiAWOWj (ORCPT ); Sun, 23 Jan 2022 09:22:39 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id A20D960C7F for ; Sun, 23 Jan 2022 14:22:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 73BA3C340E2; Sun, 23 Jan 2022 14:22:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1642947759; bh=hQJxjRi5JcJFws5lkI8WwRWOyfkRxmWS1EgrBij6h1k=; h=Subject:To:Cc:From:Date:From; b=vRyLYGHrYLnTVgnLNULqSRv02SHI6Z05FfwHfRuaOiOCJn76uBzk24ickQsjjjKew c0QcKn61kiZt9ggh5m02AnO3luP/wDBKuxQpFzbKMtcChI23ON1emt22iExF9dG5lC r+4+Vr8XbS8zXvDJExg7K1h3k83ZehV/Gj7zrSYs= Subject: FAILED: patch "[PATCH] media: cec-pin: fix interrupt en/disable handling" failed to apply to 4.19-stable tree To: hverkuil-cisco@xs4all.nl, mchehab+huawei@kernel.org, stable@vger.kernel.org Cc: From: Date: Sun, 23 Jan 2022 15:22:36 +0100 Message-ID: <1642947756113132@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 713bdfa10b5957053811470d298def9537d9ff13 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Wed, 1 Dec 2021 13:41:25 +0100 Subject: [PATCH] media: cec-pin: fix interrupt en/disable handling The en/disable_irq() functions keep track of the 'depth': i.e. if interrupts are disabled twice, then it needs to enable_irq() calls to enable them again. The cec-pin framework didn't take this into accound and could disable irqs multiple times, and it expected that a single enable_irq() would enable them again. Move all calls to en/disable_irq() to the kthread where it is easy to keep track of the current irq state and ensure that multiple en/disable_irq calls never happen. If interrupts where disabled twice, then they would never turn on again, leaving the CEC adapter in a dead state. Signed-off-by: Hans Verkuil Fixes: 865463fc03ed (media: cec-pin: add error injection support) Cc: Signed-off-by: Mauro Carvalho Chehab diff --git a/drivers/media/cec/core/cec-pin.c b/drivers/media/cec/core/cec-pin.c index 2b6459df1e94..21f0f749713e 100644 --- a/drivers/media/cec/core/cec-pin.c +++ b/drivers/media/cec/core/cec-pin.c @@ -1033,6 +1033,7 @@ static int cec_pin_thread_func(void *_adap) { struct cec_adapter *adap = _adap; struct cec_pin *pin = adap->pin; + bool irq_enabled = false; for (;;) { wait_event_interruptible(pin->kthread_waitq, @@ -1060,6 +1061,7 @@ static int cec_pin_thread_func(void *_adap) ns_to_ktime(pin->work_rx_msg.rx_ts)); msg->len = 0; } + if (pin->work_tx_status) { unsigned int tx_status = pin->work_tx_status; @@ -1083,27 +1085,39 @@ static int cec_pin_thread_func(void *_adap) switch (atomic_xchg(&pin->work_irq_change, CEC_PIN_IRQ_UNCHANGED)) { case CEC_PIN_IRQ_DISABLE: - pin->ops->disable_irq(adap); + if (irq_enabled) { + pin->ops->disable_irq(adap); + irq_enabled = false; + } cec_pin_high(pin); cec_pin_to_idle(pin); hrtimer_start(&pin->timer, ns_to_ktime(0), HRTIMER_MODE_REL); break; case CEC_PIN_IRQ_ENABLE: + if (irq_enabled) + break; pin->enable_irq_failed = !pin->ops->enable_irq(adap); if (pin->enable_irq_failed) { cec_pin_to_idle(pin); hrtimer_start(&pin->timer, ns_to_ktime(0), HRTIMER_MODE_REL); + } else { + irq_enabled = true; } break; default: break; } - if (kthread_should_stop()) break; } + if (pin->ops->disable_irq && irq_enabled) + pin->ops->disable_irq(adap); + hrtimer_cancel(&pin->timer); + cec_pin_read(pin); + cec_pin_to_idle(pin); + pin->state = CEC_ST_OFF; return 0; } @@ -1129,13 +1143,7 @@ static int cec_pin_adap_enable(struct cec_adapter *adap, bool enable) hrtimer_start(&pin->timer, ns_to_ktime(0), HRTIMER_MODE_REL); } else { - if (pin->ops->disable_irq) - pin->ops->disable_irq(adap); - hrtimer_cancel(&pin->timer); kthread_stop(pin->kthread); - cec_pin_read(pin); - cec_pin_to_idle(pin); - pin->state = CEC_ST_OFF; } return 0; } @@ -1156,11 +1164,8 @@ void cec_pin_start_timer(struct cec_pin *pin) if (pin->state != CEC_ST_RX_IRQ) return; - atomic_set(&pin->work_irq_change, CEC_PIN_IRQ_UNCHANGED); - pin->ops->disable_irq(pin->adap); - cec_pin_high(pin); - cec_pin_to_idle(pin); - hrtimer_start(&pin->timer, ns_to_ktime(0), HRTIMER_MODE_REL); + atomic_set(&pin->work_irq_change, CEC_PIN_IRQ_DISABLE); + wake_up_interruptible(&pin->kthread_waitq); } static int cec_pin_adap_transmit(struct cec_adapter *adap, u8 attempts,