From patchwork Sun Jul 30 12:46:56 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans Verkuil X-Patchwork-Id: 9870459 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id EC25460353 for ; Sun, 30 Jul 2017 12:47:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E35D3206AC for ; Sun, 30 Jul 2017 12:47:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D638B28592; Sun, 30 Jul 2017 12:47:06 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 41650206AC for ; Sun, 30 Jul 2017 12:47:06 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B14066E399; Sun, 30 Jul 2017 12:47:04 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from lb1-smtp-cloud7.xs4all.net (lb1-smtp-cloud7.xs4all.net [194.109.24.24]) by gabe.freedesktop.org (Postfix) with ESMTPS id 574D16E399 for ; Sun, 30 Jul 2017 12:47:03 +0000 (UTC) Received: from [192.168.2.10] ([212.251.195.8]) by smtp-cloud7.xs4all.net with ESMTPA id bncXdCbUhfjgxbncad2V1F; Sun, 30 Jul 2017 14:47:00 +0200 From: Hans Verkuil Subject: drm/msm: NULL pointer dereference in drivers/gpu/drm/msm/msm_gem_vma.c To: Maling list - DRI developers , Rob Clark , linux-arm-msm@vger.kernel.org, Archit Taneja Message-ID: Date: Sun, 30 Jul 2017 14:46:56 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 Content-Language: en-US X-CMAE-Envelope: MS4wfOFztebBNkNCYiC9Gd4GQ6BfEj2FNk0oN7orvpoOJc9KXikuPIEcu5pFsoDeil1pVAdk/OupAm2tTi3hrelhfgQEgrRO6u3mLWHnNsDpJ4QAf7EnHGjs BWPQdUXj8omW3Ps6dF7mBM0fVbyMXVT1SLCKFWBMV9gNAt5gV7aHhRW0Beso484OQOpo+eKg+MJ1hx0EvxgNnanJjZMlXDf/2PFJhvPOSQxPU+EisRU7eBPM v4H2nvigkpYiDDAP39xeUUWakfqJdAkWfisxxTJ+VfVG9Y2vlMPP/4DttNbk4tA/m3X3+hoN/PzIkjpdCZq9M03Yg3ryJjKrsqIqW5jq2yk= X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP Hi all, While I was testing the upcoming adv7533 CEC support with my Dragonboard c410 I encountered this NULL pointer dereference: [ 17.912822] Unable to handle kernel NULL pointer dereference at virtual address 000000e8 [ 17.917191] user pgtable: 4k pages, 48-bit VAs, pgd = ffff800030e9f000 [ 17.925249] [00000000000000e8] *pgd=00000000b0daf003, *pud=0000000000000000 [ 17.931650] Internal error: Oops: 96000005 [#1] PREEMPT SMP [ 17.938395] Modules linked in: btqcomsmd btqca arc4 wcn36xx mac80211 bluetooth cfg80211 ecdh_generic r8152 snd_soc_hdmi_codec adv7511 cec qcom_wcnss_pil msm mdt_loader drm_kms_helper msm_rng rng_core drm [ 17.943967] CPU: 0 PID: 1684 Comm: Xorg Tainted: G W 4.13.0-rc1-dragonboard #111 [ 17.962005] Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT) [ 17.970685] task: ffff800031236c00 task.stack: ffff800033fbc000 [ 17.977582] PC is at msm_gem_unmap_vma+0x20/0x80 [msm] [ 17.983213] LR is at put_iova+0x60/0xb8 [msm] [ 17.988303] pc : [] lr : [] pstate: 20000145 [ 17.992733] sp : ffff800033fbfb30 [ 18.000193] x29: ffff800033fbfb30 x28: ffff800030b5f000 [ 18.003407] x27: 00000000000000b4 x26: ffff0000009f8cd8 [ 18.008789] x25: 0000000000000004 x24: dead000000000100 [ 18.014085] x23: dead000000000200 x22: ffff800030b5fd40 [ 18.019379] x21: ffff800030b5fc00 x20: 0000000000000000 [ 18.024675] x19: ffff80003082bf00 x18: 0000000000000000 [ 18.029970] x17: 0000ffffb3347e70 x16: ffff000008207638 [ 18.035265] x15: 0000000000000053 x14: 0000000000000000 [ 18.040560] x13: 0000000000000038 x12: 0101010101010101 [ 18.045855] x11: 7f7f7f7f7f7f7f7f x10: 0000000000000040 [ 18.051150] x9 : ffff800030b5f038 x8 : ffff800031657b50 [ 18.056446] x7 : ffff800031657b78 x6 : 0000000000000000 [ 18.061740] x5 : 0000000000000000 x4 : 00000000b5c01000 [ 18.067036] x3 : 0000000000000000 x2 : ffff8000337bf300 [ 18.072330] x1 : ffff80003082bf00 x0 : 0000000000000000 [ 18.077629] Process Xorg (pid: 1684, stack limit = 0xffff800033fbc000) [ 18.082925] Stack: (0xffff800033fbfb30 to 0xffff800033fc0000) [ 18.089262] fb20: ffff800033fbfb60 ffff000000ac07c8 [ 18.095081] fb40: ffff80003082bf00 ffff800030b5fc90 ffff800030b5fc00 ffff000000abf4a0 [ 18.102893] fb60: ffff800033fbfba0 ffff000000ac16b0 ffff800030b5fc00 ffff8000338ff870 [ 18.110706] fb80: ffff8000338ff800 ffff800030b5fc00 ffff800030b5fda8 ffff800033fbfd80 [ 18.118518] fba0: ffff800033fbfbe0 ffff0000009d4244 ffff800030b5fc00 ffff800030b5f038 [ 18.126332] fbc0: ffff800033fbfbd0 ffff800030b5fc00 ffff800030b5f038 ffff0000009d4840 [ 18.134144] fbe0: ffff800033fbfbf0 ffff0000009d4858 ffff800033fbfc10 ffff0000009d48e4 [ 18.141955] fc00: ffff800030b5fc00 ffff8000338ffd98 ffff800033fbfc30 ffff0000009d49a4 [ 18.149768] fc20: ffff800030b5fc00 ffff800030b5f000 ffff800033fbfc60 ffff0000009d4a4c [ 18.157581] fc40: ffff800030b5f050 ffff800030b5f000 0000000000000001 ffff800030b5fc00 [ 18.165394] fc60: ffff800033fbfca0 ffff0000009d4ab0 0000000000000018 ffff800030b5f000 [ 18.173206] fc80: ffff0000009efd28 ffff800033fbfd80 ffff8000338ff800 ffff0000009d56a8 [ 18.181019] fca0: ffff800033fbfcb0 ffff0000009efd54 ffff800033fbfcc0 ffff0000009d56c8 [ 18.188831] fcc0: ffff800033fbfd00 ffff0000009d58e0 ffff0000009fa6e0 00000000c00464b4 [ 18.196643] fce0: 0000000000000004 ffff80003082b400 0000ffffea1f0e00 0000000000000000 [ 18.204456] fd00: ffff800033fbfe00 ffff000008206f0c ffff80000335caf8 ffff80003082b400 [ 18.212269] fd20: 0000ffffea1f0e00 ffff80003082b400 00000000c00464b4 0000ffffea1f0e00 [ 18.220081] fd40: 0000000000000124 000000000000001d ffff0000089d2000 ffff800031236c00 [ 18.227894] fd60: ffff800033fbfd80 0000000000000004 ffff0000009efd28 ffff800033fbfd80 [ 18.235706] fd80: 0000000100000001 0000008000000001 0000001800000020 0000000000000001 [ 18.243518] fda0: 0000000100000000 0000000100000001 0000ffff00000000 0000ffff00000000 [ 18.251331] fdc0: 0000000000000124 0000000000000038 ffff0000089d2000 ffff800031236c00 [ 18.259144] fde0: ffff800033fbfe40 ffff000008214124 ffff800033fbfe30 ffff000008203290 [ 18.266956] fe00: ffff800033fbfe80 ffff0000082076b4 0000000000000000 ffff800030d8a000 [ 18.274768] fe20: ffff80003082b400 0000000000000016 ffff800033fbfe50 ffff0000081f0488 [ 18.282581] fe40: ffff800033fbfe80 ffff000008207678 0000000000000000 ffff80003082b400 [ 18.290393] fe60: ffff800033fbfe70 ffff0000082138b0 ffff800033fbfe80 ffff000008207658 [ 18.298207] fe80: 0000000000000000 ffff000008082f84 0000000000000000 0000800034a16000 [ 18.306017] fea0: ffffffffffffffff 0000ffffb3347e7c 0000000000000000 0000000000000015 [ 18.313832] fec0: 0000000000000016 00000000c00464b4 0000ffffea1f0e00 0000000000000001 [ 18.321643] fee0: 0000000000000020 0000000000000080 0000000000000001 0000000000000000 [ 18.329456] ff00: 000000000000001d 000000012692c5b0 0101010101010101 7f7f7f7f7f7f7f7f [ 18.337269] ff20: 0101010101010101 0000000000000038 0000000000000000 0000000000000053 [ 18.345082] ff40: 0000ffffb368b2b8 0000ffffb3347e70 0000000000000000 0000ffffb3847000 [ 18.352894] ff60: 0000ffffea1f0e00 00000000c00464b4 0000000000000016 0000ffffea1f0edc [ 18.360705] ff80: 000000012692ad20 0000000000000003 00000001214282e4 0000000121428388 [ 18.368518] ffa0: 0000000000000000 0000ffffea1f0da0 0000ffffb367185c 0000ffffea1f0da0 [ 18.376332] ffc0: 0000ffffb3347e7c 0000000000000000 0000000000000016 000000000000001d [ 18.384142] ffe0: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [ 18.391953] Call trace: [ 18.399760] Exception stack(0xffff800033fbf950 to 0xffff800033fbfa80) [ 18.402023] f940: ffff80003082bf00 0001000000000000 [ 18.408622] f960: ffff800033fbfb30 ffff000000ac2d58 0000000020000145 ffff8000338ffa78 [ 18.416435] f980: 0000000000000000 0000000000000000 ffff800033fbf9e0 ffff0000089afcf0 [ 18.424248] f9a0: ffff80000348f230 ffff8000338ffa78 0000000000000000 0000000000000000 [ 18.432060] f9c0: ffff8000338ffaa8 0000000000000001 ffff800033fbfb80 ffff0000009e8f38 [ 18.439872] f9e0: ffff800033fbfa10 ffff0000089a9ff8 0000000000000027 ffff80003082b918 [ 18.447684] fa00: 0000000000000000 ffff80003082bf00 ffff8000337bf300 0000000000000000 [ 18.455497] fa20: 00000000b5c01000 0000000000000000 0000000000000000 ffff800031657b78 [ 18.463310] fa40: ffff800031657b50 ffff800030b5f038 0000000000000040 7f7f7f7f7f7f7f7f [ 18.471122] fa60: 0101010101010101 0000000000000038 0000000000000000 0000000000000053 [ 18.479062] [] msm_gem_unmap_vma+0x20/0x80 [msm] [ 18.486862] [] put_iova+0x60/0xb8 [msm] [ 18.492938] [] msm_gem_free_object+0x60/0x198 [msm] [ 18.498432] [] drm_gem_object_free+0x1c/0x58 [drm] [ 18.504854] [] drm_gem_object_put_unlocked+0x90/0xa0 [drm] [ 18.511273] [] drm_gem_object_handle_put_unlocked+0x64/0xd0 [drm] [ 18.518300] [] drm_gem_object_release_handle+0x54/0x98 [drm] [ 18.525679] [] drm_gem_handle_delete+0x64/0xb8 [drm] [ 18.532968] [] drm_gem_dumb_destroy+0x10/0x18 [drm] [ 18.539479] [] drm_mode_destroy_dumb_ioctl+0x2c/0x40 [drm] [ 18.545992] [] drm_ioctl_kernel+0x68/0xe0 [drm] [ 18.553105] [] drm_ioctl+0x178/0x3b0 [drm] [ 18.558970] [] do_vfs_ioctl+0xa4/0x7d0 [ 18.564694] [] SyS_ioctl+0x7c/0x98 [ 18.569992] [] el0_svc_naked+0x38/0x3c [ 18.574941] Code: a90153f3 aa0003f4 f90013f5 aa0103f3 (f9407400) [ 18.580502] ---[ end trace b1ac6888ec40b0be ]--- It turns out that the aspace argument in msm_gem_unmap_vma() is NULL. This quick hack prevents the NULL pointer dereference and the HDMI output behaves itself again: I have might just be addressing a symptom and not the cause as I have no idea what is happening here. But on the off-chance that I am actually right: Signed-off-by: Hans Verkuil Regards, Hans diff --git a/drivers/gpu/drm/msm/msm_gem_vma.c b/drivers/gpu/drm/msm/msm_gem_vma.c index c36321bc8714..d34e331554f3 100644 --- a/drivers/gpu/drm/msm/msm_gem_vma.c +++ b/drivers/gpu/drm/msm/msm_gem_vma.c @@ -42,7 +42,7 @@ void msm_gem_unmap_vma(struct msm_gem_address_space *aspace, struct msm_gem_vma *vma, struct sg_table *sgt) { - if (!vma->iova) + if (!aspace || !vma->iova) return; if (aspace->mmu) {