From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7F855C43334 for ; Fri, 3 Jun 2022 17:42:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344970AbiFCRmz (ORCPT ); Fri, 3 Jun 2022 13:42:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56830 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344790AbiFCRmh (ORCPT ); Fri, 3 Jun 2022 13:42:37 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 26A50544E9; Fri, 3 Jun 2022 10:41:41 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 6830FB82431; Fri, 3 Jun 2022 17:41:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9B032C385B8; Fri, 3 Jun 2022 17:41:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1654278098; bh=q2NHZY4zoWxPt27Lq/7DgmJDwWrfmAtyHIJvatc+/Pw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cC4Qema9YA58kBBe6hXm5eYVNH8rlAHiHWeoIL49PnVnPeZ5E8UttKp8cfLtIerrK cKL0LZ0SeTyKunRKRbs1ydKAApyeCmmmkeArOg/M5vUv0eRRl9m4U/aMKdLFZzNgUD pE1n+RAZwqsjwj3af//khmIXuz6EvEBtEmaFD9HQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jeremi Piotrowski , Dusty Mabe , Salvatore Bonaccorso , Thomas Gleixner , Noah Meyerhans , Noah Meyerhans Subject: [PATCH 4.19 01/30] x86/pci/xen: Disable PCI/MSI[-X] masking for XEN_HVM guests Date: Fri, 3 Jun 2022 19:39:29 +0200 Message-Id: <20220603173815.133022212@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220603173815.088143764@linuxfoundation.org> References: <20220603173815.088143764@linuxfoundation.org> User-Agent: quilt/0.66 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Thomas Gleixner commit 7e0815b3e09986d2fe651199363e135b9358132a upstream. When a XEN_HVM guest uses the XEN PIRQ/Eventchannel mechanism, then PCI/MSI[-X] masking is solely controlled by the hypervisor, but contrary to XEN_PV guests this does not disable PCI/MSI[-X] masking in the PCI/MSI layer. This can lead to a situation where the PCI/MSI layer masks an MSI[-X] interrupt and the hypervisor grants the write despite the fact that it already requested the interrupt. As a consequence interrupt delivery on the affected device is not happening ever. Set pci_msi_ignore_mask to prevent that like it's done for XEN_PV guests already. Fixes: 809f9267bbab ("xen: map MSIs into pirqs") Reported-by: Jeremi Piotrowski Reported-by: Dusty Mabe Reported-by: Salvatore Bonaccorso Signed-off-by: Thomas Gleixner Tested-by: Noah Meyerhans Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/87tuaduxj5.ffs@tglx [nmeyerha@amazon.com: backported to 4.19] Signed-off-by: Noah Meyerhans Signed-off-by: Greg Kroah-Hartman --- arch/x86/pci/xen.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/arch/x86/pci/xen.c +++ b/arch/x86/pci/xen.c @@ -441,6 +441,11 @@ void __init xen_msi_init(void) x86_msi.setup_msi_irqs = xen_hvm_setup_msi_irqs; x86_msi.teardown_msi_irq = xen_teardown_msi_irq; + /* + * With XEN PIRQ/Eventchannels in use PCI/MSI[-X] masking is solely + * controlled by the hypervisor. + */ + pci_msi_ignore_mask = 1; } #endif