From patchwork Tue Jan 7 20:53:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 234274 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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 BCE28C282DD for ; Tue, 7 Jan 2020 21:23:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 886522087F for ; Tue, 7 Jan 2020 21:23:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578432231; bh=I5bT0UnOd1vvZOD2Zxl7tad9MKt1oDNX/jejXGiWtr8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=YDzqMYFI6RC6FOTr7YPWy5E3n4lOl865usXCwiQdsCA20NlMEQnXrOFYxxn5bMJ9C SdpVMzoWDsRXxK8c/4YAaiR6LKj3dfQxQCutQNY/pHvksNluNXwjaVL36SVYJsCCwG uoUkuVj6cIGJCq/ABSw63QT0gILIaVjZ/TN64Mkk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727209AbgAGVXq (ORCPT ); Tue, 7 Jan 2020 16:23:46 -0500 Received: from mail.kernel.org ([198.145.29.99]:37782 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727267AbgAGVBI (ORCPT ); Tue, 7 Jan 2020 16:01:08 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E2E3224656; Tue, 7 Jan 2020 21:01:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578430867; bh=I5bT0UnOd1vvZOD2Zxl7tad9MKt1oDNX/jejXGiWtr8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XFIGlIExJm01kGZv9gcjaH2b5c/Dts/GH1prcdK1n/84c1Kq+vZrNde7TsWLzWfj9 NmU80nnpq6keK+AwIMNElKNdUgwDVu6zWyj7QJxPbj5BJjsSejRFJf9CvaN77g6IXn 5YCtpC5eI3Kz7Kndm9GvLntkcsea314pTCwQAIHQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hans Verkuil , Mauro Carvalho Chehab Subject: [PATCH 5.4 082/191] media: cec: check transmit_in_progress, not transmitting Date: Tue, 7 Jan 2020 21:53:22 +0100 Message-Id: <20200107205337.370595839@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200107205332.984228665@linuxfoundation.org> References: <20200107205332.984228665@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Hans Verkuil commit ac479b51f3f4aaa852b5d3f00ecfb9290230cf64 upstream. Currently wait_event_interruptible_timeout is called in cec_thread_func() when adap->transmitting is set. But if the adapter is unconfigured while transmitting, then adap->transmitting is set to NULL. But the hardware is still actually transmitting the message, and that's indicated by adap->transmit_in_progress and we should wait until that is finished or times out before transmitting new messages. As the original commit says: adap->transmitting is the userspace view, adap->transmit_in_progress reflects the hardware state. However, if adap->transmitting is NULL and adap->transmit_in_progress is true, then wait_event_interruptible is called (no timeout), which can get stuck indefinitely if the CEC driver is flaky and never marks the transmit-in-progress as 'done'. So test against transmit_in_progress when deciding whether to use the timeout variant or not, instead of testing against adap->transmitting. Signed-off-by: Hans Verkuil Fixes: 32804fcb612b ("media: cec: keep track of outstanding transmits") Cc: # for v4.19 and up Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/cec/cec-adap.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) --- a/drivers/media/cec/cec-adap.c +++ b/drivers/media/cec/cec-adap.c @@ -463,7 +463,7 @@ int cec_thread_func(void *_adap) bool timeout = false; u8 attempts; - if (adap->transmitting) { + if (adap->transmit_in_progress) { int err; /* @@ -498,7 +498,7 @@ int cec_thread_func(void *_adap) goto unlock; } - if (adap->transmitting && timeout) { + if (adap->transmit_in_progress && timeout) { /* * If we timeout, then log that. Normally this does * not happen and it is an indication of a faulty CEC @@ -507,14 +507,18 @@ int cec_thread_func(void *_adap) * so much traffic on the bus that the adapter was * unable to transmit for CEC_XFER_TIMEOUT_MS (2.1s). */ - pr_warn("cec-%s: message %*ph timed out\n", adap->name, - adap->transmitting->msg.len, - adap->transmitting->msg.msg); + if (adap->transmitting) { + pr_warn("cec-%s: message %*ph timed out\n", adap->name, + adap->transmitting->msg.len, + adap->transmitting->msg.msg); + /* Just give up on this. */ + cec_data_cancel(adap->transmitting, + CEC_TX_STATUS_TIMEOUT); + } else { + pr_warn("cec-%s: transmit timed out\n", adap->name); + } adap->transmit_in_progress = false; adap->tx_timeouts++; - /* Just give up on this. */ - cec_data_cancel(adap->transmitting, - CEC_TX_STATUS_TIMEOUT); goto unlock; }