From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 16BCC60869; Tue, 30 Jan 2024 10:07:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706609271; cv=none; b=ScLQTSvX3hDJJ7l8sX/W8IhZ0YjnVw5Vg+TsmU/3yOREB+z0IMzfyt7oTu01Oe8l5CDj6Gku0HfP8VqRErbgnb3DouiNt5dWNPD72CAj+t0HeZIkLyX2bQ0rtF0NdZVXVlZx7MmqMvAHkg7L8G/e4qSyC8ca4Oq+9v8vj67N7/8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706609271; c=relaxed/simple; bh=8CKJrkkGZM/Di0WcrrdDLyXgOONeUOLpOJVPXsgvDfc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=gHuYMJoh8CaV/ZfSDlaiVZ23rAc3ek/kxbQBaShDvmqjCg6lbEIGQV7h4P9dci5dZsLECvfJ2PCeTUiIGaNgvS4wrHBg6PycCgXuNH6QkMi5PfWHfnvFS27hR9Bn1UKTMSzd1n8zfT+x7j8+ljFmE/c79hNpKvIvPV7oQYFldGE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=oXjU7ZJV; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="oXjU7ZJV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 92A63C43394; Tue, 30 Jan 2024 10:07:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1706609270; bh=8CKJrkkGZM/Di0WcrrdDLyXgOONeUOLpOJVPXsgvDfc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=oXjU7ZJVNQetTKK+iu7bcpvfWtFQHKDYE888Y16U4NH5V/n7E9rrIu1Ei+fhqxJ1C aTJ/Hl/ukgxMj9wx17vqA7bZiJvKh131t5jj5sRt/z5PFd41VoUVWGO6YColmMbyMh GBPJ3XabbpiUYPRbKUPm5eh/XYRMpDk6JSGHWcZRpOYSA9pXVf8Yp1a7JPCoJKK9tc j011Q3TokZY8sC5v0t+K0Y3vc204C5daTI/DJ+S0FMqtS2yhNr6f2/ba4Rk9gBruif jxzuBfQ2wkaSrugKhbz0XIhldCgUmbqRTF6UzbTO0rjUaHZahAB6kg3FsMd5qnrp+T rSSlSOaf6POow== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1rUl1u-000000002uC-18CJ; Tue, 30 Jan 2024 11:07:46 +0100 Date: Tue, 30 Jan 2024 11:07:46 +0100 From: Johan Hovold To: Bjorn Helgaas Cc: Michael Schaller , Kai-Heng Feng , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, regressions@lists.linux.dev, "Maciej W . Rozycki" , Ajay Agarwal , Kuppuswamy Sathyanarayanan , Greg Kroah-Hartman , Heiner Kallweit , Johan Hovold , Bjorn Helgaas , stable@vger.kernel.org, regressions@leemhuis.info Subject: Re: PCI/ASPM locking regression in 6.7-final (was: Re: [PATCH] Revert "PCI/ASPM: Remove pcie_aspm_pm_state_change()") Message-ID: References: <20240123223648.GA331671@bhelgaas> Precedence: bulk X-Mailing-List: stable@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: On Wed, Jan 24, 2024 at 09:16:38AM +0100, Johan Hovold wrote: > On Tue, Jan 23, 2024 at 04:36:48PM -0600, Bjorn Helgaas wrote: > > I don't quite follow. By simply reverting, do you mean to revert > > f93e71aea6c6 ("Revert "PCI/ASPM: Remove > > pcie_aspm_pm_state_change()"")? IIUC that would break Michael's > > machine again. > > Right, at least until that issue is fully understood and alternative > fixes have been considered. > > If that's not an option, we need to rework core to pass a flag through > more than one layer to indicate whether pcie_aspm_pm_state_change() > should take the bus semaphore or not. I'd rather not do that if it can > be avoided. As a revert appears unlikely to happen, let's fix the regression by adding a new helper pci_set_power_state_locked() that can be called with the bus lock held: https://lore.kernel.org/lkml/20240130100243.11011-1-johan+linaro@kernel.org/ Johan