From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.9]) (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 143B514A0A4 for ; Thu, 11 Apr 2024 11:55:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.9 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712836534; cv=none; b=F6lu1W5HDUbwXiyT9dxxoR8uuPmSDRNAqXboHZB44z+/AIvk/nruvzMlh3Wy4BgFqb02TziK0wsQrMi1vc5an7TLmGAe62va+fSRVHAAOCplC88Ss+92U2xJZdF2/AlZ5dWSbOnZeCkeHvD0bKnViLvvzySiJH/2cW0y3NWLFAI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712836534; c=relaxed/simple; bh=alXo0H8ANdaI1GJGeUlWdQEWdSZmaHDInU3myDZ1M5Q=; h=Message-ID:Date:MIME-Version:Cc:Subject:From:To:References: In-Reply-To:Content-Type; b=f9ARIXqolcSuypZwXXVzIjiKxNCzwJvsA7CyTuGBcE0J2+/3M/QR3LOxr/W0JMy5uOvZT6phEweicoMSP17RKaYipQH9l3o8ItVQzHbdZi6rl32bnj6h+yzmX9vdaNW3r8E/dCCih+Fzktkh3K4HWwvwizL0hpSC0nef61/jyXs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=X1FkFekt; arc=none smtp.client-ip=198.175.65.9 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="X1FkFekt" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1712836533; x=1744372533; h=message-id:date:mime-version:cc:subject:from:to: references:in-reply-to:content-transfer-encoding; bh=alXo0H8ANdaI1GJGeUlWdQEWdSZmaHDInU3myDZ1M5Q=; b=X1FkFekt1xqwtcZLRZXNh0wxGgir6wzuoWQa9uucx41mpQ0xWdjbmW7v BNEA3p9Nt/kwJSBEmqTmbCOiqkkcSE30D8rV6FSQAzOOLtoXcavM/izrn 3EhB9d2GWkWnO987pelw3App7rXK7b035p0nmVWKi0yxuHNwY8kOgHhfb tmFu60r7kld9dNFzGhg4tqL7o7bCSXyQoEXgAueSCgvWTzY4kFLAfI+yq tS7YqZ+jU17nT2jlhBJYdJDsT93hF8qfs1IEYiy0OhJwgBVoV9/LPgM89 Ax380LLoRKXkzzA94wy7Q7p/BGyJoWAYFsaM+3wGBn5s7e3lF2BVbcK7k Q==; X-CSE-ConnectionGUID: EAdMRYFBSS6inQG8fDvrUA== X-CSE-MsgGUID: waUSnDCrSFSplcpSIYjU1A== X-IronPort-AV: E=McAfee;i="6600,9927,11039"; a="30721963" X-IronPort-AV: E=Sophos;i="6.07,193,1708416000"; d="scan'208";a="30721963" Received: from orviesa002.jf.intel.com ([10.64.159.142]) by orvoesa101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Apr 2024 04:55:33 -0700 X-CSE-ConnectionGUID: LvEhbi8zSCCUwyc42P2LpA== X-CSE-MsgGUID: 8OVffHXmQnqfIrIkENzLUg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.07,193,1708416000"; d="scan'208";a="51845828" Received: from blu2-mobl.ccr.corp.intel.com (HELO [10.124.237.86]) ([10.124.237.86]) by orviesa002-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Apr 2024 04:55:31 -0700 Message-ID: Date: Thu, 11 Apr 2024 19:55:28 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: Jacob Pan , Xuchun Shang , iommu@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/3] iommu/vt-d: Fix WARN_ON in iommu probe path From: Baolu Lu To: Joerg Roedel , Kevin Tian References: <20240411030744.273460-1-baolu.lu@linux.intel.com> <20240411030744.273460-4-baolu.lu@linux.intel.com> Content-Language: en-US In-Reply-To: <20240411030744.273460-4-baolu.lu@linux.intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2024/4/11 11:07, Lu Baolu wrote: > Commit 1a75cc710b95 ("iommu/vt-d: Use rbtree to track iommu probed > devices") adds all devices probed by the iommu driver in a rbtree > indexed by the source ID of each device. It assumes that each device > has a unique source ID. This assumption is incorrect and the VT-d > spec doesn't state this requirement either. > > The reason for using a rbtree to track devices is to look up the device > with PCI bus and devfunc in the paths of handling ATS invalidation time > out error and the PRI I/O page faults. Both are PCI ATS feature related. > > Only track the devices that have PCI ATS capabilities in the rbtree to > avoid unnecessary WARN_ON in the iommu probe path. Otherwise, on some > platforms below kernel splat will be displayed and the iommu probe results > in failure. > > WARNING: CPU: 3 PID: 166 at drivers/iommu/intel/iommu.c:158 intel_iommu_probe_device+0x319/0xd90 > Call Trace: > > ? __warn+0x7e/0x180 > ? intel_iommu_probe_device+0x319/0xd90 > ? report_bug+0x1f8/0x200 > ? handle_bug+0x3c/0x70 > ? exc_invalid_op+0x18/0x70 > ? asm_exc_invalid_op+0x1a/0x20 > ? intel_iommu_probe_device+0x319/0xd90 > ? debug_mutex_init+0x37/0x50 > __iommu_probe_device+0xf2/0x4f0 > iommu_probe_device+0x22/0x70 > iommu_bus_notifier+0x1e/0x40 > notifier_call_chain+0x46/0x150 > blocking_notifier_call_chain+0x42/0x60 > bus_notify+0x2f/0x50 > device_add+0x5ed/0x7e0 > platform_device_add+0xf5/0x240 > mfd_add_devices+0x3f9/0x500 > ? preempt_count_add+0x4c/0xa0 > ? up_write+0xa2/0x1b0 > ? __debugfs_create_file+0xe3/0x150 > intel_lpss_probe+0x49f/0x5b0 > ? pci_conf1_write+0xa3/0xf0 > intel_lpss_pci_probe+0xcf/0x110 [intel_lpss_pci] > pci_device_probe+0x95/0x120 > really_probe+0xd9/0x370 > ? __pfx___driver_attach+0x10/0x10 > __driver_probe_device+0x73/0x150 > driver_probe_device+0x19/0xa0 > __driver_attach+0xb6/0x180 > ? __pfx___driver_attach+0x10/0x10 > bus_for_each_dev+0x77/0xd0 > bus_add_driver+0x114/0x210 > driver_register+0x5b/0x110 > ? __pfx_intel_lpss_pci_driver_init+0x10/0x10 [intel_lpss_pci] > do_one_initcall+0x57/0x2b0 > ? kmalloc_trace+0x21e/0x280 > ? do_init_module+0x1e/0x210 > do_init_module+0x5f/0x210 > load_module+0x1d37/0x1fc0 > ? init_module_from_file+0x86/0xd0 > init_module_from_file+0x86/0xd0 > idempotent_init_module+0x17c/0x230 > __x64_sys_finit_module+0x56/0xb0 > do_syscall_64+0x6e/0x140 > entry_SYSCALL_64_after_hwframe+0x71/0x79 > > Fixes: 1a75cc710b95 ("iommu/vt-d: Use rbtree to track iommu probed devices") > Closes:https://gitlab.freedesktop.org/drm/intel/-/issues/10689 > Signed-off-by: Lu Baolu > Link:https://lore.kernel.org/r/20240407011429.136282-1-baolu.lu@linux.intel.com > --- > drivers/iommu/intel/iommu.c | 11 +++++++---- > 1 file changed, 7 insertions(+), 4 deletions(-) Kevin gave his r-b. https://lore.kernel.org/linux-iommu/BN9PR11MB52768106FE4890D6481E73178C052@BN9PR11MB5276.namprd11.prod.outlook.com/ Include that in the pull request so that b4 can pick it up. Reviewed-by: Kevin Tian