From nobody Thu Jan 8 14:31:06 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) client-ip=192.237.175.120; envelope-from=xen-devel-bounces@lists.xenproject.org; helo=lists.xenproject.org; Received-SPF: pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) client-ip=192.237.175.120; envelope-from=xen-devel-bounces@lists.xenproject.org; helo=lists.xenproject.org; Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=pass(p=quarantine dis=none) header.from=suse.com ARC-Seal: i=1; a=rsa-sha256; t=1766044611; cv=none; d=zohomail.com; s=zohoarc; b=O/nI9zazWX8HrqqlDjbKdEAE0O6sl9FLsVHPGabyFI4cjsooNz6kL9/jSLWBi/cbxQy5cmjlC9Rln/lHbqIiP2GK/Xou2BCkoS5Z1SDDnYPEWvcFVJkZ8rh2DjvxntUoWnP/Br5f8n3clT/87pgsJn72wMSBYR6pkv6pjECFQ8U= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1766044611; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:List-Subscribe:List-Post:List-Id:List-Help:List-Unsubscribe:MIME-Version:Message-ID:Sender:Subject:Subject:To:To:Message-Id:Reply-To; bh=/819DSxskHvW6Dh9rErBDLF7kFwnJ3mm2P4u44VQT5s=; b=Go3m6hFYZy4WppYFGvIW8TuWerDLCmhK+gUdSgfgdHqhjcDRogBYJksIVHPCyp99j82X7HcE9UOmyscKcjAo8ucSSxVt7Iwaz+AAyl1cnm8E43+fCFlSqfeEYapsVZjsDTu0JoU4FFSx2qvbvaNwQQnH5kgKzCGl4ExREIxvj7g= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=pass header.from= (p=quarantine dis=none) Return-Path: Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) by mx.zohomail.com with SMTPS id 1766044611093256.809885687866; Wed, 17 Dec 2025 23:56:51 -0800 (PST) Received: from list by lists.xenproject.org with outflank-mailman.1189273.1510082 (Exim 4.92) (envelope-from ) id 1vW8s9-0003aH-G9; Thu, 18 Dec 2025 07:56:29 +0000 Received: by outflank-mailman (output) from mailman id 1189273.1510082; Thu, 18 Dec 2025 07:56:29 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1vW8s9-0003aA-DY; Thu, 18 Dec 2025 07:56:29 +0000 Received: by outflank-mailman (input) for mailman id 1189273; Thu, 18 Dec 2025 07:56:28 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1vW8s7-0003Zr-W7 for xen-devel@lists.xenproject.org; Thu, 18 Dec 2025 07:56:28 +0000 Received: from mail-wr1-x432.google.com (mail-wr1-x432.google.com [2a00:1450:4864:20::432]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id 0e112494-dbe7-11f0-b15b-2bf370ae4941; Thu, 18 Dec 2025 08:56:27 +0100 (CET) Received: by mail-wr1-x432.google.com with SMTP id ffacd0b85a97d-42fbc305882so136093f8f.0 for ; Wed, 17 Dec 2025 23:56:27 -0800 (PST) Received: from [10.156.60.236] (ip-037-024-206-209.um08.pools.vodafone-ip.de. [37.24.206.209]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-43244998ca0sm3397102f8f.32.2025.12.17.23.56.25 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 17 Dec 2025 23:56:26 -0800 (PST) X-Outflank-Mailman: Message body and most headers restored to incoming version X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 0e112494-dbe7-11f0-b15b-2bf370ae4941 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1766044586; x=1766649386; darn=lists.xenproject.org; h=content-transfer-encoding:autocrypt:subject:from:cc:to :content-language:user-agent:mime-version:date:message-id:from:to:cc :subject:date:message-id:reply-to; bh=/819DSxskHvW6Dh9rErBDLF7kFwnJ3mm2P4u44VQT5s=; b=AVBAGi3oMvEPxXuadYz2jEd2hjncdbpMRgQD7hfv+sIOmhBJTe7b8WE0N2lyikj8LG LpKdeA8cxRaprmSb7miRtVFclh+PYlTad+GKpT+tmlW/R1bJx6UfMNh5ruwmeShXkggt ykTp60pk+5ZRA4SlDXLYgeAUTCvl7XVzvfA+aH4Xk3Xl089zvnugeSfulsXc2V/hSvld 9VhjWN+uWZnAYSxy649VYc6QQTaFaHQ0pRmSEBNhMnX95hdniDPFJX9lFhz2vbTmkQFf RYKzv3YUi//qKQtxCzUsnN73WNaf1RKWYxLY4dHAH9ZZs0AiaVMl7szGhLVXMzBXBSpP e7xQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1766044586; x=1766649386; h=content-transfer-encoding:autocrypt:subject:from:cc:to :content-language:user-agent:mime-version:date:message-id:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=/819DSxskHvW6Dh9rErBDLF7kFwnJ3mm2P4u44VQT5s=; b=Ci+oiL0ovNzItYgNs3Er0lp8h+7cABXCnBx2UKnA6x0wogp8NBYzp89MUOXwPqwQOZ iuQUsM+U4B6kwzMQRpYPXZR0Kw6yAPbZTp5utIyIQDXRUp7MXT8Q+uJyCPFkQ9Th/PVo CNS3IhfTLdlmInoPL5lFgp71DCOiNtPEtjdM/hnEZIfJOTHQvSDf9MxpO484XPQz7a8k sK4IBi7k2fEaFgA8crKDwvJojByAA9uYW2QOxgibvC6quoeF5/6eOKkCElEhvC0N+vX1 sPpK/mfgTvIJo3drvYozNTDmGLCwA/dzljJ0ryHLkjMJvyh0IxQdC2D73FQLto263RlZ k0mw== X-Gm-Message-State: AOJu0YwNk4WTeYypErKyM+rexHnu5yYmFQtbLGfoc6fx+glhx16eC+96 qvxfW3Gn8e4foArrygI3AcHHNitGCYm+3GHOruYbK+9GLQ4fQ018Ons4qlxl22sS36glw+feWZF jk04= X-Gm-Gg: AY/fxX52mlP63CLwcHOq7vlsIQ2bssTZ1ie7vfAU7rZYnzghYbl3GR+qrEwtusqEKBK kEUMxyjXd0xd073f0E/0dxQAF88yvTjwEF9AmAu20AW6EqMgF3k+/SoN+qqv3juGZkZqKH4+t/3 gdUCwxjsKOMJ+VOegzwRmFM0yrQaU58HLEvnM5ZLfxDXyC9qH1KkpTBLLzX8jZ148MB/A1ZL150 8/vjoB9fNs8H8iVNR/Ko09dgNEAA8H/gsx9b5WnNVGKYnsJTiewRmh0m3r1htAyVahbKqv9FzoD Nd1eKbaIQSJOEZZrC8Vl+WkbXafSHyVrmPSyRoUhIRYGQsaujr7zIZ9vCHTqj0YSovp6cnmkWGs HJ5dS61gLFJlXRdB3vfpFw56fYMjltMpJE9dyG8qqOAJGHTVojGZKyRNg903RRdvv0nZxnOg91O oduvkMrOuNZfw99FKnth/8800oUfxpP21RUxBWzUnmU7OZLyRTQ7Ey+5Nvh7JkelY/lmG/gzUBO BM= X-Google-Smtp-Source: AGHT+IEJ/R1bhdowa6vmOAcvppKj7sS3TouoYj0keMc88ZyxiOZRt7fGasY56V5suKaGd1uo+g4exA== X-Received: by 2002:a05:6000:2909:b0:42f:9f18:8f40 with SMTP id ffacd0b85a97d-42fb490cedemr22593402f8f.42.1766044586337; Wed, 17 Dec 2025 23:56:26 -0800 (PST) Message-ID: <26294a6d-e99b-4290-988a-da7b7b838651@suse.com> Date: Thu, 18 Dec 2025 08:56:24 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Content-Language: en-US To: "xen-devel@lists.xenproject.org" Cc: =?UTF-8?Q?Roger_Pau_Monn=C3=A9?= , Chen Jiqian From: Jan Beulich Subject: [PATCH] vPCI: avoid bogus "overlap in extended cap list" warnings Autocrypt: addr=jbeulich@suse.com; keydata= xsDiBFk3nEQRBADAEaSw6zC/EJkiwGPXbWtPxl2xCdSoeepS07jW8UgcHNurfHvUzogEq5xk hu507c3BarVjyWCJOylMNR98Yd8VqD9UfmX0Hb8/BrA+Hl6/DB/eqGptrf4BSRwcZQM32aZK 7Pj2XbGWIUrZrd70x1eAP9QE3P79Y2oLrsCgbZJfEwCgvz9JjGmQqQkRiTVzlZVCJYcyGGsD /0tbFCzD2h20ahe8rC1gbb3K3qk+LpBtvjBu1RY9drYk0NymiGbJWZgab6t1jM7sk2vuf0Py O9Hf9XBmK0uE9IgMaiCpc32XV9oASz6UJebwkX+zF2jG5I1BfnO9g7KlotcA/v5ClMjgo6Gl MDY4HxoSRu3i1cqqSDtVlt+AOVBJBACrZcnHAUSuCXBPy0jOlBhxPqRWv6ND4c9PH1xjQ3NP nxJuMBS8rnNg22uyfAgmBKNLpLgAGVRMZGaGoJObGf72s6TeIqKJo/LtggAS9qAUiuKVnygo 3wjfkS9A3DRO+SpU7JqWdsveeIQyeyEJ/8PTowmSQLakF+3fote9ybzd880fSmFuIEJldWxp Y2ggPGpiZXVsaWNoQHN1c2UuY29tPsJgBBMRAgAgBQJZN5xEAhsDBgsJCAcDAgQVAggDBBYC AwECHgECF4AACgkQoDSui/t3IH4J+wCfQ5jHdEjCRHj23O/5ttg9r9OIruwAn3103WUITZee e7Sbg12UgcQ5lv7SzsFNBFk3nEQQCACCuTjCjFOUdi5Nm244F+78kLghRcin/awv+IrTcIWF hUpSs1Y91iQQ7KItirz5uwCPlwejSJDQJLIS+QtJHaXDXeV6NI0Uef1hP20+y8qydDiVkv6l IreXjTb7DvksRgJNvCkWtYnlS3mYvQ9NzS9PhyALWbXnH6sIJd2O9lKS1Mrfq+y0IXCP10eS FFGg+Av3IQeFatkJAyju0PPthyTqxSI4lZYuJVPknzgaeuJv/2NccrPvmeDg6Coe7ZIeQ8Yj t0ARxu2xytAkkLCel1Lz1WLmwLstV30g80nkgZf/wr+/BXJW/oIvRlonUkxv+IbBM3dX2OV8 AmRv1ySWPTP7AAMFB/9PQK/VtlNUJvg8GXj9ootzrteGfVZVVT4XBJkfwBcpC/XcPzldjv+3 HYudvpdNK3lLujXeA5fLOH+Z/G9WBc5pFVSMocI71I8bT8lIAzreg0WvkWg5V2WZsUMlnDL9 mpwIGFhlbM3gfDMs7MPMu8YQRFVdUvtSpaAs8OFfGQ0ia3LGZcjA6Ik2+xcqscEJzNH+qh8V m5jjp28yZgaqTaRbg3M/+MTbMpicpZuqF4rnB0AQD12/3BNWDR6bmh+EkYSMcEIpQmBM51qM EKYTQGybRCjpnKHGOxG0rfFY1085mBDZCH5Kx0cl0HVJuQKC+dV2ZY5AqjcKwAxpE75MLFkr wkkEGBECAAkFAlk3nEQCGwwACgkQoDSui/t3IH7nnwCfcJWUDUFKdCsBH/E5d+0ZnMQi+G0A nAuWpQkjM1ASeQwSHEeAWPgskBQL Content-Transfer-Encoding: quoted-printable X-ZohoMail-DKIM: pass (identity @suse.com) X-ZM-MESSAGEID: 1766044614512158500 Content-Type: text/plain; charset="utf-8" Legacy PCI devices don't have any extended config space. Reading any part thereof may very well return all ones. That then necessarily means we would think we found a "loop", when there simply is nothing. Fixes: a845b50c12f3 ("vpci/header: Emulate extended capability list for dom= 0") Signed-off-by: Jan Beulich Acked-by: Roger Pau Monn=C3=A9 --- This is the minimalistic change to get rid of "overlap in extended cap list" warnings I'm observing. We may want to avoid any attempt to access extended config space when there is none - see Linux'es pci_cfg_space_size() and it helper pci_cfg_space_size_ext(). This would then also avoid us interpreting as an extended cap list what isn't one at all (some legacy PCI devices don't decode register address bits 9-11, some return other non-0, non-all-ones data). Including the risk of reading a register with read side effects. Thoughts? The DomU part of the function worries me as well. Rather than making it "read 0, write ignore" for just the first 32 bits, shouldn't we make it so for the entire extended config space, and shouldn't we also make it "read all ones, write ignore" when there is no extended config space in the first place (then in particular also for the first 32 bits)? Should we perhaps also log a warning if we exit the loop with non-zero "pos"? --- a/xen/drivers/vpci/header.c +++ b/xen/drivers/vpci/header.c @@ -839,6 +839,15 @@ static int vpci_init_ext_capability_list uint32_t header =3D pci_conf_read32(pdev->sbdf, pos); int rc; =20 + if ( header =3D=3D 0xffffffff ) + { + if ( pos !=3D PCI_CFG_SPACE_SIZE ) + printk(XENLOG_WARNING + "%pd %pp: broken extended cap list, offset %#x\n", + pdev->domain, &pdev->sbdf, pos); + return 0; + } + rc =3D vpci_add_register(pdev->vpci, vpci_read_val, NULL, pos, 4, (void *)(uintptr_t)header); if ( rc =3D=3D -EEXIST )