From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755919AbdJPWHF (ORCPT ); Mon, 16 Oct 2017 18:07:05 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:53612 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753432AbdJPWHE (ORCPT ); Mon, 16 Oct 2017 18:07:04 -0400 Date: Tue, 17 Oct 2017 00:06:56 +0200 (CEST) From: Thomas Gleixner To: Dexuan Cui cc: Bjorn Helgaas , KY Srinivasan , Stephen Hemminger , "linux-pci@vger.kernel.org" , "devel@linuxdriverproject.org" , "linux-kernel@vger.kernel.org" , Josh Poulson , Haiyang Zhang , Simon Xiao , Saeed Mahameed , "Mihai Costache (Cloudbase Solutions SRL)" , Jork Loeser Subject: Re: [PATCH] PCI: hv: fix "spurious APIC interrupt" due to new vector reservation mode In-Reply-To: Message-ID: References: User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 14 Oct 2017, Dexuan Cui wrote: > Last month the vector management code was reworked, and as a result of the > changes, e.g. commit 22d0b12f3560 ("genirq/irqdomain: Add force > reactivation flag to irq domains"), commit 4900be83602b ("x86/vector/msi: > Switch to global reservation mode") etc, now we must add this new flag > MSI_FLAG_MUST_REACTIVATE when calling pci_msi_create_irq_domain() on x86, > otherwise Hyper-V PCIe pass-through can't work, and we get: > "spurious APIC interrupt through vector ff on CPU#0, should never happen", > this is because no valid MSI/MSI-X vector is allocated. > > Signed-off-by: Dexuan Cui > Cc: Thomas Gleixner > Cc: Bjorn Helgaas > Cc: K. Y. Srinivasan > Cc: Haiyang Zhang > Cc: Stephen Hemminger > --- > > Currently the "reservation mode" patchset has not been in Linus's tree yet, so > today's mainline hasn't shown the issue, but today's linux-next has shown the > issue (PCIe pass-through on Hyper-V can't work). > > I think any caller of pci_msi_create_irq_domain() that runs on x86 needs to > be updated, but besides pci-hyper I'm not sure which callers run on x86. I'm sure I thought about adding something to pci_msi_create_irq_domain() in the first place, but then forgot about it again. I'll have a look tomorrow morning. Thanks, tglx