From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [78.32.30.218]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A0BFE1DD88F; Thu, 31 Jul 2025 16:28:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=78.32.30.218 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753979333; cv=none; b=Xu4SZhtW2dibyepR+uqNGLA5Nhfvma3e6yb8VXE74COCHBI+JSXeL472yYfN1OCR9QE1hoqkkuJrj8VXGVxluh5StJFjMGXn5lcRmHEIXSCeakrbepquIRqdZLqDEYc+U6D68RD+8yHsLHKviVN8ivCKM7PIttC9Wigg+KKOIBU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753979333; c=relaxed/simple; bh=EZq1onKeGbOCYgztz4cXy6ukiKrLEvoFTODQY8N+SQ4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=gTjMD+BSV2DrG5whdk2Cqhb5CoR7WNoCRVam1/jWphp8N4nIyeN8p1kzq3VQfpmByzO19GBE6fCDDuhFb4X3+kUHV21CP01nWxkAxhCiSGrYAxs+IjNkPI7Ygp1TNuYGxPK02eruuYq3RlvQkRMAme8tJ1AcFrNCQHwMkVnpS3s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=armlinux.org.uk; spf=none smtp.mailfrom=armlinux.org.uk; dkim=pass (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b=HK+zaTKR; arc=none smtp.client-ip=78.32.30.218 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=armlinux.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=armlinux.org.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="HK+zaTKR" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=YWwp4TE/YPh29hTFAA70aDsjbLV0IDUmerqb9zc6zYg=; b=HK+zaTKR3ZRMhUuu8sKrxTzaXg TNwjQ0hByJDkHtLX8JJKeUhFZPssrtEo+crCkgN3Usm7kVT+e/4j24f3fMVWxf3gIj9BOw1VnrBI0 UYTASiUFQWgGTWPHSi+GiAPdpTGT3D1gl3tyG24sN2qoD1I68+m5PwlFlSTKtA7RxuYyWTNlCgjQZ 5sEcQCgmD4+fRi5G/c3JK7lCMuevi0IcTAqGKVq1mt0ZMJfJm39VlmnD6oR4stteeRkRv3iKIdwG9 VH8BYm0+fvuup7HzFTGzF/jD3tm8zNKiHpYQwaCpc2e00pyjwnbvNmansnI4QfRLQ7UHaHC66W/PJ 2J2u4mzw==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:39196) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1uhW94-0005G5-2G; Thu, 31 Jul 2025 17:28:42 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.96) (envelope-from ) id 1uhW92-0001Ar-0C; Thu, 31 Jul 2025 17:28:40 +0100 Date: Thu, 31 Jul 2025 17:28:39 +0100 From: "Russell King (Oracle)" To: Mark Brown Cc: Krzysztof Kozlowski , Chanwoo Choi , Alexandre Belloni , Linus Walleij , Bartosz Golaszewski , linux-gpio@vger.kernel.org, linux-rtc@vger.kernel.org, linux-kernel@vger.kernel.org, Thierry Reding Subject: Re: [BUG] 6.16-rc7: lockdep failure with max77620-gpio/max77686-rtc Message-ID: References: <97f0e27f-3128-4821-bc09-2acde1ebf81a@kernel.org> <68c210a2-49b2-4fd2-97ad-27af85369d9f@sirena.org.uk> <4f80be02-0bbe-4c10-a3d2-324916ea2ca4@sirena.org.uk> <14c68c29-68d8-4119-8f70-616c07397dc4@sirena.org.uk> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <14c68c29-68d8-4119-8f70-616c07397dc4@sirena.org.uk> Sender: Russell King (Oracle) On Thu, Jul 31, 2025 at 05:16:13PM +0100, Mark Brown wrote: > On Thu, Jul 31, 2025 at 04:57:42PM +0100, Russell King (Oracle) wrote: > > On Thu, Jul 31, 2025 at 02:18:24PM +0100, Mark Brown wrote: > > > > I *think* mutex_lock_nested() is what we're looking for here, with the > > > depth information from the irq_desc but I'm also not super familiar with > > > this stuff. > > > I'm not sure about that, because the irq_desc locks don't nest: > > > raw_spin_lock_init(&desc->lock); > > lockdep_set_class(&desc->lock, &irq_desc_lock_class); > > > What saves irq_desc lock nesting in this case is that > > __irq_put_desc_unlock() unlocks desc->lock calling the > > irq_bus_sync_unlock() method. So, I don't think we have anything at > > the irq_desc level which deals with lock-nesting. > > Yeah, and that's all internals which we're not super encouraged to peer > at. There should be something that'll give us a nesting level > somewhere... > > Lockdep's handling of nesting is generally fun. As I said, I'm just going to disable lockdep to shut up the warning and not pursue any further time on this. If someone else cares about it (which I doubt) they can try to come up with a solution. I suspect nested regmap-irq is extremely rare. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!