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 smtp1.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 63097C43334 for ; Fri, 24 Jun 2022 00:55:19 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id C7D6384798; Fri, 24 Jun 2022 00:55:18 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org C7D6384798 Authentication-Results: smtp1.osuosl.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=faI+eiHJ X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Ha9MUjndLekc; Fri, 24 Jun 2022 00:55:17 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [IPv6:2605:bc80:3010:104::8cd3:938]) by smtp1.osuosl.org (Postfix) with ESMTPS id C35CD84795; Fri, 24 Jun 2022 00:55:16 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org C35CD84795 Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 8FDBDC0032; Fri, 24 Jun 2022 00:55:16 +0000 (UTC) Received: from smtp3.osuosl.org (smtp3.osuosl.org [IPv6:2605:bc80:3010::136]) by lists.linuxfoundation.org (Postfix) with ESMTP id 8CEA1C002D for ; Fri, 24 Jun 2022 00:55:15 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id 5311E60BE1 for ; Fri, 24 Jun 2022 00:55:15 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp3.osuosl.org 5311E60BE1 Authentication-Results: smtp3.osuosl.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=faI+eiHJ X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id S6Wbv1v6qPRg for ; Fri, 24 Jun 2022 00:55:13 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp3.osuosl.org DF7DD60BB1 Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by smtp3.osuosl.org (Postfix) with ESMTPS id DF7DD60BB1 for ; Fri, 24 Jun 2022 00:55:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1656032112; x=1687568112; h=message-id:date:mime-version:cc:subject:to:references: from:in-reply-to:content-transfer-encoding; bh=PA8xe1s8KSwd8s5ArY8C3K1kz59dLQKimlFAN3yCtl4=; b=faI+eiHJhHXKZ28aSM1jFSbn1k3AIgK7s4/JNIIYE418/ubNT7TIWvO+ QFfAZ+0MhbUGYWWP3gDqj9f010dlDhnOaXwpNrW0e7WIUeDYIuBSZQqm9 yys8LwUWT66+3MzOMxKelu5IzycSidcuuE0fRlNgrOON7Gitru4IXqK6n DQIsOCmNEDlrPI8rJ4ws4GB62G0PEeB4TI+f0sAub1j5rmjVvS2kNm15j m78GVtNQ49MLi/MLeTAgOs//YsDDWOw1P8Dbylxg5rUHNIwk/DCZ51mA7 csbqVWUS8glzJCGfe7yMQ9rTemp37e855OZmVij5/tEh0709wEB8FIQ4t w==; X-IronPort-AV: E=McAfee;i="6400,9594,10387"; a="281966976" X-IronPort-AV: E=Sophos;i="5.92,217,1650956400"; d="scan'208";a="281966976" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Jun 2022 17:55:11 -0700 X-IronPort-AV: E=Sophos;i="5.92,217,1650956400"; d="scan'208";a="645023733" Received: from wenli3x-mobl.ccr.corp.intel.com (HELO [10.249.168.117]) ([10.249.168.117]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Jun 2022 17:55:09 -0700 Message-ID: <6639b21c-1544-a025-4da5-219a1608f06e@linux.intel.com> Date: Fri, 24 Jun 2022 08:55:08 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: iommu_sva_bind_device question Content-Language: en-US To: Jerry Snitselaar , iommu@lists.linux-foundation.org, Dave Jiang , dmaengine@vger.kernel.org References: <20220623170232.6whonfjuh3m5vcoy@cantor> From: Baolu Lu In-Reply-To: <20220623170232.6whonfjuh3m5vcoy@cantor> X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On 2022/6/24 01:02, Jerry Snitselaar wrote: > Hi Baolu & Dave, > > I noticed last night that on a Sapphire Rapids system if you boot without > intel_iommu=on, the idxd driver will crash during probe in iommu_sva_bind_device(). > Should there be a sanity check before calling dev_iommu_ops(), or is the expectation > that the caller would verify it is safe to call? This seemed to be uncovered by > the combination of 3f6634d997db ("iommu: Use right way to retrieve iommu_ops"), and > 42a1b73852c4 ("dmaengine: idxd: Separate user and kernel pasid enabling"). > > [ 21.423729] BUG: kernel NULL pointer dereference, address: 0000000000000038 > [ 21.445108] #PF: supervisor read access in kernel mode > [ 21.450912] #PF: error_code(0x0000) - not-present page > [ 21.456706] PGD 0 > [ 21.459047] Oops: 0000 [#1] PREEMPT SMP NOPTI > [ 21.464004] CPU: 0 PID: 1420 Comm: kworker/0:3 Not tainted 5.19.0-0.rc3.27.eln120.x86_64 #1 > [ 21.464011] Hardware name: Intel Corporation EAGLESTREAM/EAGLESTREAM, BIOS EGSDCRB1.SYS.0067.D12.2110190954 10/19/2021 > [ 21.464015] Workqueue: events work_for_cpu_fn > [ 21.464030] RIP: 0010:iommu_sva_bind_device+0x1d/0xe0 > [ 21.464046] Code: c3 cc 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 41 57 41 56 49 89 d6 41 55 41 54 55 53 48 83 ec 08 48 8b 87 d8 02 00 00 <48> 8b 40 38 48 8b 50 10 48 83 7a 70 00 48 89 14 24 0f 84 91 00 00 > [ 21.464050] RSP: 0018:ff7245d9096b7db8 EFLAGS: 00010296 > [ 21.464054] RAX: 0000000000000000 RBX: ff1eadeec8a51000 RCX: 0000000000000000 > [ 21.464058] RDX: ff7245d9096b7e24 RSI: 0000000000000000 RDI: ff1eadeec8a510d0 > [ 21.464060] RBP: ff1eadeec8a51000 R08: ffffffffb1a12300 R09: ff1eadffbfce25b4 > [ 21.464062] R10: ffffffffffffffff R11: 0000000000000038 R12: ffffffffc09f8000 > [ 21.464065] R13: ff1eadeec8a510d0 R14: ff7245d9096b7e24 R15: ff1eaddf54429000 > [ 21.464067] FS: 0000000000000000(0000) GS:ff1eadee7f600000(0000) knlGS:0000000000000000 > [ 21.464070] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 21.464072] CR2: 0000000000000038 CR3: 00000008c0e10006 CR4: 0000000000771ef0 > [ 21.464074] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > [ 21.464076] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400 > [ 21.464078] PKRU: 55555554 > [ 21.464079] Call Trace: > [ 21.464083] > [ 21.464092] idxd_pci_probe+0x259/0x1070 [idxd] > [ 21.464121] local_pci_probe+0x3e/0x80 > [ 21.464132] work_for_cpu_fn+0x13/0x20 > [ 21.464136] process_one_work+0x1c4/0x380 > [ 21.464143] worker_thread+0x1ab/0x380 > [ 21.464147] ? _raw_spin_lock_irqsave+0x23/0x50 > [ 21.464158] ? process_one_work+0x380/0x380 > [ 21.464161] kthread+0xe6/0x110 > [ 21.464168] ? kthread_complete_and_exit+0x20/0x20 > [ 21.464172] ret_from_fork+0x1f/0x30 > > I figure either there needs to be a check in iommu_sva_bind_device, or > idxd needs to check in idxd_enable_system_pasid that that > idxd->pdev->dev.iommu is not null before it tries calling iommu_sva_bind_device. As documented around the iommu_sva_bind_device() interface: * iommu_dev_enable_feature(dev, IOMMU_DEV_FEAT_SVA) must be called first, to * initialize the required SVA features. idxd->pdev->dev.iommu should be checked in there. Dave, any thoughts? Best regards, baolu _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu