Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752725AbdGCI6C (ORCPT ); Mon, 3 Jul 2017 04:58:02 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:59194 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751734AbdGCI57 (ORCPT ); Mon, 3 Jul 2017 04:57:59 -0400 Cc: Sudeep Holla , LKML , Alexey Klimov , Jassi Brar Subject: Re: [PATCH 1/2] mailbox: reset txdone_method TXDONE_BY_POLL if client knows_txdone To: Jassi Brar References: <1498835681-23975-1-git-send-email-sudeep.holla@arm.com> From: Sudeep Holla Organization: ARM Message-ID: <3c542b86-4de1-3c97-5e2d-1335115ac9a3@arm.com> Date: Mon, 3 Jul 2017 09:57:56 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.1.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2127 Lines: 55 On 01/07/17 12:25, Jassi Brar wrote: > On Fri, Jun 30, 2017 at 8:44 PM, Sudeep Holla wrote: >> Currently the mailbox framework sets txdone_method to TXDONE_BY_POLL if >> the controller sets txdone_by_poll. However some clients can have a >> mechanism to do TXDONE_BY_ACK which they can specify by knows_txdone. >> However, we endup setting both TXDONE_BY_POLL and TXDONE_BY_ACK in that >> case. In such scenario, we may end up with below warnings as the tx >> ticker is run both by mailbox framework and the client. >> >> WARNING: CPU: 1 PID: 0 at kernel/time/hrtimer.c:805 hrtimer_forward+0x88/0xd8 >> CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.12.0-rc5 #242 >> Hardware name: ARM LTD ARM Juno Development Platform >> task: ffff8009768ca700 task.stack: ffff8009768f8000 >> PC is at hrtimer_forward+0x88/0xd8 >> LR is at txdone_hrtimer+0xd4/0xf8 >> Call trace: >> hrtimer_forward+0x88/0xd8 >> __hrtimer_run_queues+0xe4/0x158 >> hrtimer_interrupt+0xa4/0x220 >> arch_timer_handler_phys+0x30/0x40 >> handle_percpu_devid_irq+0x78/0x130 >> generic_handle_irq+0x24/0x38 >> __handle_domain_irq+0x5c/0xb8 >> gic_handle_irq+0x54/0xa8 >> >> This patch fixes the issue by resetting TXDONE_BY_POLL if client has set >> knows_txdone. >> >> Cc: Alexey Klimov >> Cc: Jassi Brar >> Signed-off-by: Sudeep Holla >> --- >> drivers/mailbox/mailbox.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c >> index 537f4f6d009b..8da30f833262 100644 >> --- a/drivers/mailbox/mailbox.c >> +++ b/drivers/mailbox/mailbox.c >> @@ -351,7 +351,7 @@ struct mbox_chan *mbox_request_channel(struct mbox_client *cl, int index) >> init_completion(&chan->tx_complete); >> >> if (chan->txdone_method == TXDONE_BY_POLL && cl->knows_txdone) >> - chan->txdone_method |= TXDONE_BY_ACK; >> + chan->txdone_method = TXDONE_BY_ACK; >> > It has to be restored back in mbox_free_channel() Ah right, will fix and repost. -- Regards, Sudeep