From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bmailout3.hostsharing.net (bmailout3.hostsharing.net [176.9.242.62]) (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 F26A51BE86E; Tue, 1 Oct 2024 11:07:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=176.9.242.62 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727780842; cv=none; b=K67UlZFi8r34L/5Vf4eHu+DVirWl1gCyTDPoms7VxvQT6eiNLh7morfbPt3YunHZdZ5WagcGtoWXCYkt3Lzl3eskRm09/wxCKlruLOltpGUB1XvBJufLDi/txUgu4/tk5NOict1J0WjpUK1EwkR1DMAglUInv8D1+KiWcpW9ZGU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727780842; c=relaxed/simple; bh=weurZ7f6r0W/k0PPpMVi8YHvf9LeKhQs/vfB2a1/Kzc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=WBxJkgrKGms0O/yW/33MMl9ciY4nCyPjooEKWsS931izi6iNjLDmcS7sj2/Bfyvm2aSOel0vKi3rH+C61G5EPtAU8+qrW/vpOOzE14+gosKhXMpq0dKWgYI0ATXB4vN2xt2lUgvwjF76qTshwIa43j2e2cdIJsiJz9W7OWZe5B8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=wunner.de; spf=none smtp.mailfrom=h08.hostsharing.net; arc=none smtp.client-ip=176.9.242.62 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=wunner.de Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=h08.hostsharing.net Received: from h08.hostsharing.net (h08.hostsharing.net [83.223.95.28]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "*.hostsharing.net", Issuer "RapidSSL TLS RSA CA G1" (verified OK)) by bmailout3.hostsharing.net (Postfix) with ESMTPS id 76EF5100D9429; Tue, 1 Oct 2024 13:07:18 +0200 (CEST) Received: by h08.hostsharing.net (Postfix, from userid 100393) id 507095008; Tue, 1 Oct 2024 13:07:18 +0200 (CEST) Date: Tue, 1 Oct 2024 13:07:18 +0200 From: Lukas Wunner To: AceLan Kao Cc: Bjorn Helgaas , Ilpo =?iso-8859-1?Q?J=E4rvinen?= , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] PCI: pciehp: Fix system hang on resume after hot-unplug during suspend Message-ID: References: <20240926125909.2362244-1-acelan.kao@canonical.com> 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: On Mon, Sep 30, 2024 at 11:27:28AM +0800, AceLan Kao wrote: > Lukas Wunner 2024 9 27 5:28 > > there is a known issue > > that a deadlock may occur when hot-removing nested PCIe switches (which is > > what you've got here). Keith Busch recently re-discovered the issue. > > You may want to try if the hang goes away if you apply this patch: > > > > https://lore.kernel.org/all/20240612181625.3604512-2-kbusch@meta.com/ > > > > If it does go away then at least we know what the root cause is. > > Yes, the 2 patches work. Okay so you can't reproduce the issue with those patches? That would mean 9d573d19547b ("PCI: pciehp: Detect device replacement during system sleep") isn't the culprit, whew! > > The patch is a bit hackish, but there's an ongoing effort to tackle the > > problem more thoroughly: > > > > https://lore.kernel.org/all/20240722151936.1452299-1-kbusch@meta.com/ > > https://lore.kernel.org/all/20240827192826.710031-1-kbusch@meta.com/ > > v2 can't be applied clearly, so I made some changes. > And this series doesn't work for me. Okay, I'll look at those patches separately. Thanks, Lukas