From patchwork Sun Jun 26 05:16:48 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jerry Snitselaar X-Patchwork-Id: 12895597 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 12CC4C43334 for ; Sun, 26 Jun 2022 05:16:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233788AbiFZFQ6 (ORCPT ); Sun, 26 Jun 2022 01:16:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60234 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230269AbiFZFQ5 (ORCPT ); Sun, 26 Jun 2022 01:16:57 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id B72D211812 for ; Sat, 25 Jun 2022 22:16:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1656220615; 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: in-reply-to:in-reply-to:references:references; bh=AqqLkZ8qs63LGYXJWLYH7qSzKVlxiJgdi7CcXHtcQxE=; b=LNX12RHBJvdM477KpcXNh83wI+UNygkAECYHkRcjaRKfDhRshuadsiyma/Ke5b5wzq5oRK 6sqEfEBXWS2QAm9ZydfoU0h2Zuj5JaoYHdewU9qcsaTTAcZXJF1r0nPra+G5E9XBSXmwVL 1zgOy9b1YeLEPaCgP8PrDOZXVnuD7VU= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-176-_A4Pmc9OPFqg63sX1_jbWg-1; Sun, 26 Jun 2022 01:16:52 -0400 X-MC-Unique: _A4Pmc9OPFqg63sX1_jbWg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id B078D803524; Sun, 26 Jun 2022 05:16:51 +0000 (UTC) Received: from cantor.redhat.com (unknown [10.2.16.4]) by smtp.corp.redhat.com (Postfix) with ESMTP id 07FC22026D64; Sun, 26 Jun 2022 05:16:50 +0000 (UTC) From: Jerry Snitselaar To: dmaengine@vger.kernel.org Cc: Vinod Koul , linux-kernel@vger.kernel.org, Dave Jiang , Fenghua Yu Subject: [PATCH v3] dmaengine: idxd: Only call idxd_enable_system_pasid() if succeeded in enabling SVA feature Date: Sat, 25 Jun 2022 22:16:48 -0700 Message-Id: <20220626051648.14249-1-jsnitsel@redhat.com> In-Reply-To: <20220625221333.214589-1-jsnitsel@redhat.com> References: <20220625221333.214589-1-jsnitsel@redhat.com> MIME-Version: 1.0 Content-type: text/plain X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org On a Sapphire Rapids system if boot without intel_iommu=on, the IDXD driver will crash during probe in iommu_sva_bind_device(). [ 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 iommu_sva_bind_device() requires SVA has been enabled successfully on the IDXD device before it's called. Otherwise, iommu_sva_bind_device() will access a NULL pointer. If Intel IOMMU is disabled, SVA cannot be enabled and thus idxd_enable_system_pasid() and iommu_sva_bind_device() should not be called. Fixes: 42a1b73852c4 ("dmaengine: idxd: Separate user and kernel pasid enabling") Cc: Vinod Koul Cc: linux-kernel@vger.kernel.org Cc: Dave Jiang Cc: Fenghua Yu Link: https://lore.kernel.org/dmaengine/20220623170232.6whonfjuh3m5vcoy@cantor/ Signed-off-by: Jerry Snitselaar Acked-by: Fenghua Yu --- v3: Move changelog. Add lore link. Remove you. v2: Balance braces on if else block. Fix up commit description. drivers/dma/idxd/init.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c index 355fb3ef4cbf..aa3478257ddb 100644 --- a/drivers/dma/idxd/init.c +++ b/drivers/dma/idxd/init.c @@ -512,15 +512,16 @@ static int idxd_probe(struct idxd_device *idxd) dev_dbg(dev, "IDXD reset complete\n"); if (IS_ENABLED(CONFIG_INTEL_IDXD_SVM) && sva) { - if (iommu_dev_enable_feature(dev, IOMMU_DEV_FEAT_SVA)) + if (iommu_dev_enable_feature(dev, IOMMU_DEV_FEAT_SVA)) { dev_warn(dev, "Unable to turn on user SVA feature.\n"); - else + } else { set_bit(IDXD_FLAG_USER_PASID_ENABLED, &idxd->flags); - if (idxd_enable_system_pasid(idxd)) - dev_warn(dev, "No in-kernel DMA with PASID.\n"); - else - set_bit(IDXD_FLAG_PASID_ENABLED, &idxd->flags); + if (idxd_enable_system_pasid(idxd)) + dev_warn(dev, "No in-kernel DMA with PASID.\n"); + else + set_bit(IDXD_FLAG_PASID_ENABLED, &idxd->flags); + } } else if (!sva) { dev_warn(dev, "User forced SVA off via module param.\n"); }