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 X-Spam-Level: X-Spam-Status: No, score=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DD090C35280 for ; Fri, 1 May 2020 21:41:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A5028208DB for ; Fri, 1 May 2020 21:41:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="XOE7VHvx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726859AbgEAVlc (ORCPT ); Fri, 1 May 2020 17:41:32 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:47971 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726381AbgEAVlc (ORCPT ); Fri, 1 May 2020 17:41:32 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1588369291; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=na8QnBz7W2Ii0eveaJBlRsX241pOL+BoPANtqMrwttE=; b=XOE7VHvxJxQc4nCQ88aGNprK4Vn3G1piZHMccoF68UoVgQ2qAbZjfJRc4wzupbtD1y0cmU 5AzyRzirTkLqR/YnNPi2UAnnVT89N7uwzE4peG/Z5JtpCCKjsdiW7PRwwtIVEsnPCzRuog 0Ymv3oWvLkAMsbAxu8IB4oHUiUrRcwE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-503-3SfWvdkbNrmSPRf_Im86qw-1; Fri, 01 May 2020 17:41:29 -0400 X-MC-Unique: 3SfWvdkbNrmSPRf_Im86qw-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5DC7A100CCC3; Fri, 1 May 2020 21:41:28 +0000 (UTC) Received: from gimli.home (ovpn-113-95.phx2.redhat.com [10.3.113.95]) by smtp.corp.redhat.com (Postfix) with ESMTP id 14AE55C1B0; Fri, 1 May 2020 21:41:25 +0000 (UTC) Subject: [PATCH] vfio-pci: Mask cap zero From: Alex Williamson To: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org, cohuck@redhat.com Date: Fri, 01 May 2020 15:41:24 -0600 Message-ID: <158836927527.9272.16785800801999547009.stgit@gimli.home> User-Agent: StGit/0.19-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There is no PCI spec defined capability with ID 0, therefore we don't expect to find it in a capability chain and we use this index in an internal array for tracking the sizes of various capabilities to handle standard config space. Therefore if a device does present us with a capability ID 0, we mark our capability map with nonsense that can trigger conflicts with other capabilities in the chain. Ignore ID 0 when walking the capability chain, handling it as a hidden capability. Seen on an NVIDIA Tesla T4. Signed-off-by: Alex Williamson --- drivers/vfio/pci/vfio_pci_config.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c index 87d0cc8c86ad..5935a804cb88 100644 --- a/drivers/vfio/pci/vfio_pci_config.c +++ b/drivers/vfio/pci/vfio_pci_config.c @@ -1487,7 +1487,7 @@ static int vfio_cap_init(struct vfio_pci_device *vdev) if (ret) return ret; - if (cap <= PCI_CAP_ID_MAX) { + if (cap && cap <= PCI_CAP_ID_MAX) { len = pci_cap_length[cap]; if (len == 0xFF) { /* Variable length */ len = vfio_cap_len(vdev, cap, pos);