From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Grygorii.Strashko@linaro.org" Subject: Re: [PATCH] gpio: pcf875x: Revert "gpio: pcf857x: Propagate wake-up setting to parent irq controller" Date: Thu, 14 May 2015 15:32:05 +0300 Message-ID: <555495C5.3040904@linaro.org> References: <1431353601-21295-1-git-send-email-rogerq@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-wg0-f48.google.com ([74.125.82.48]:34607 "EHLO mail-wg0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932420AbbENMcM (ORCPT ); Thu, 14 May 2015 08:32:12 -0400 Received: by wguv19 with SMTP id v19so11646278wgu.1 for ; Thu, 14 May 2015 05:32:11 -0700 (PDT) In-Reply-To: Sender: linux-gpio-owner@vger.kernel.org List-Id: linux-gpio@vger.kernel.org To: Geert Uytterhoeven , Roger Quadros Cc: Linus Walleij , Alexandre Courbot , "linux-gpio@vger.kernel.org" , "linux-omap@vger.kernel.org" , Thomas Gleixner , "linux-kernel@vger.kernel.org" Hi, On 05/11/2015 08:36 PM, Geert Uytterhoeven wrote: > On Mon, May 11, 2015 at 4:13 PM, Roger Quadros wrote: >> commit b80eef95beb0 ('gpio: pcf857x: Propagate wake-up setting to parent irq controller') >> introduces the following recursive locking warning while suspending dra7-evm. >> >> The issue addressed by that commit has been already resolved by >> commit 10a50f1ab5f0 ('genirq: Set IRQCHIP_SKIP_SET_WAKE flag for dummy_irq_chip') > > That's not 100% correct: commit b80eef95beb0 ('gpio: pcf857x: Propagate wake-up > setting to parent irq controller') fixes _two_ things: > 1. warning due to missing irq_set_wake / IRQCHIP_SKIP_SET_WAKE, > 2. propagating set_wake, so the parent interrupt controller stays awake, as > it's needed for wake-up, > > Only the first issue is addressed by commit 10a50f1ab5f0 ('genirq: Set > IRQCHIP_SKIP_SET_WAKE flag for dummy_irq_chip'). > >> and so let's revert commit b80eef95beb0 ('gpio: pcf857x: Propagate wake-up setting to parent irq controller') >> >> At least the recursive locking message no longer appears after the revert. >> >> [ 30.591905] PM: Syncing filesystems ... done. >> [ 30.623060] Freezing user space processes ... (elapsed 0.003 seconds) done. >> [ 30.634470] Freezing remaining freezable tasks ... (elapsed 0.002 seconds) done. >> [ 30.658288] sd 0:0:0:0: [sda] Synchronizing SCSI cache >> [ 30.663678] >> [ 30.663681] ============================================= >> [ 30.663683] [ INFO: possible recursive locking detected ] >> [ 30.663688] 4.1.0-rc3 #1115 Not tainted >> [ 30.663693] --------------------------------------------- >> [ 30.663697] suspend.sh/2319 is trying to acquire lock: >> [ 30.663719] (class){......}, at: [] __irq_get_desc_lock+0x48/0x88 >> [ 30.663722] >> [ 30.663722] but task is already holding lock: >> [ 30.663734] (class){......}, at: [] __irq_get_desc_lock+0x48/0x88 > > Does this mean .set_irq_wake() cannot call irq_set_irq_wake()? > Many GPIO drivers do that, as they need to propagate wake-up state to the > parent interrupt controller? As I remember, there was similar problem, so I found corresponding patch (just FYI) ab2b926 mfd: Fix twl6030 lockdep recursion warning on setting wake IRQs Not sure such kind of solution is the best choice ( -- regards, -grygorii