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 9F8BB14A09C for ; Thu, 4 Sep 2025 13:18:52 +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=1756991934; cv=none; b=cwhG/APaQHTxCGGKODTkVboH9gBD5/+H8hnmJal4PzbQuVdAEOJc3QzoLgnr+0C6/J0F73HnXYVWMsE4HpaKHw/TdNo9z82PY/iu4d5LV58IqqG2fKIWGAhH2yqKgSpmibyxBCBn+ZBq6mI/pgprLRmP11EyUrBfbiSQvBP5EXM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756991934; c=relaxed/simple; bh=d+rQQSyh8vj+YqtJr3kqnnWjk1+tY0I/9RcBj+IL++k=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=u78lZzdYu+IFjCayI+ZEu4jqB0U2gs5LqyJ+dUJyVeaSrXuJLwzIVwh1v+GbnV55IiYmb4ZwKdTgyB9yELpO3lr4IgOyB5sy2NChBUc5XhfixUeb7hZ6wqQ9oTxgglNb84bkfrOH0VTbYaJ3V2/ePJukw/hXoxyTgXBTQMR0b6g= 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 F09FC2C051D9; Thu, 4 Sep 2025 15:18:50 +0200 (CEST) Received: by h08.hostsharing.net (Postfix, from userid 100393) id C360A36B940; Thu, 4 Sep 2025 15:18:50 +0200 (CEST) Date: Thu, 4 Sep 2025 15:18:50 +0200 From: Lukas Wunner To: Sebastian Andrzej Siewior Cc: Crystal Wood , Bjorn Helgaas , Mahesh J Salgaonkar , Oliver O'Halloran , Clark Williams , Steven Rostedt , Attila Fazekas , linux-pci@vger.kernel.org, linux-rt-devel@lists.linux.dev Subject: Re: [PATCH] PCI/AER: Use IRQF_NO_THREAD on aer_irq Message-ID: References: <20250902224441.368483-1-crwood@redhat.com> <20250904073024.YsLeZqK_@linutronix.de> Precedence: bulk X-Mailing-List: linux-pci@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 Thu, Sep 04, 2025 at 02:48:21PM +0200, Lukas Wunner wrote: > On Thu, Sep 04, 2025 at 09:30:24AM +0200, Sebastian Andrzej Siewior wrote: > > On 2025-09-02 17:44:41 [-0500], Crystal Wood wrote: > > > +++ b/drivers/pci/pcie/aer.c > > > @@ -1671,7 +1671,8 @@ static int aer_probe(struct pcie_device *dev) > > > set_service_data(dev, rpc); > > > > > > status = devm_request_threaded_irq(device, dev->irq, aer_irq, aer_isr, > > > - IRQF_SHARED, "aerdrv", dev); > > > + IRQF_NO_THREAD | IRQF_SHARED, > > > + "aerdrv", dev); > > > > I'm not sure if this works with IRQF_SHARED. Your primary handler is > > IRQF_SHARED + IRQF_NO_THREAD and another shared handler which is > > forced-threaded will have IRQF_SHARED + IRQF_ONESHOT. > > If the core does not complain, all good. Worst case might be the shared > > ONESHOT lets your primary handler starve. It would be nice if you could > > check if you have shared handler here (I have no aer I three boxes I > > checked). > > Yes, interrupt sharing can happen if the Root Port uses legacy INTx > interrupts. In that case other port services such as hotplug, > bandwidth control, PME or DPC may use the same interrupt. I should add that none of these other port service drivers use IRQF_ONESHOT. They're all IRQF_SHARED only. Thanks, Lukas