From patchwork Fri Aug 7 06:24:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mansur Alisha Shaik X-Patchwork-Id: 256229 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C23BBC433E1 for ; Fri, 7 Aug 2020 06:25:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AF59B221E5 for ; Fri, 7 Aug 2020 06:25:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726622AbgHGGZO (ORCPT ); Fri, 7 Aug 2020 02:25:14 -0400 Received: from alexa-out.qualcomm.com ([129.46.98.28]:62166 "EHLO alexa-out.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726401AbgHGGZD (ORCPT ); Fri, 7 Aug 2020 02:25:03 -0400 Received: from ironmsg09-lv.qualcomm.com ([10.47.202.153]) by alexa-out.qualcomm.com with ESMTP; 06 Aug 2020 23:25:03 -0700 Received: from ironmsg01-blr.qualcomm.com ([10.86.208.130]) by ironmsg09-lv.qualcomm.com with ESMTP/TLS/AES256-SHA; 06 Aug 2020 23:25:02 -0700 Received: from c-mansur-linux.qualcomm.com ([10.204.90.208]) by ironmsg01-blr.qualcomm.com with ESMTP; 07 Aug 2020 11:54:50 +0530 Received: by c-mansur-linux.qualcomm.com (Postfix, from userid 461723) id 06DEA21C70; Fri, 7 Aug 2020 11:54:49 +0530 (IST) From: Mansur Alisha Shaik To: linux-media@vger.kernel.org, stanimir.varbanov@linaro.org Cc: linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, vgarodia@codeaurora.org, Mansur Alisha Shaik Subject: [RESEND 1/3] venus: core: handle race condititon for core ops Date: Fri, 7 Aug 2020 11:54:36 +0530 Message-Id: <1596781478-12216-2-git-send-email-mansur@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1596781478-12216-1-git-send-email-mansur@codeaurora.org> References: <1596781478-12216-1-git-send-email-mansur@codeaurora.org> Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org For core ops we are having only write protect but there is no read protect, because of this in multthreading and concurrency, one CPU core is reading without wait which is causing the NULL pointer dereferece crash. one such scenario is as show below, where in one core core->ops becoming NULL and in another core calling core->ops->session_init(). CPU: core-7: Call trace: hfi_session_init+0x180/0x1dc [venus_core] vdec_queue_setup+0x9c/0x364 [venus_dec] vb2_core_reqbufs+0x1e4/0x368 [videobuf2_common] vb2_reqbufs+0x4c/0x64 [videobuf2_v4l2] v4l2_m2m_reqbufs+0x50/0x84 [v4l2_mem2mem] v4l2_m2m_ioctl_reqbufs+0x2c/0x38 [v4l2_mem2mem] v4l_reqbufs+0x4c/0x5c __video_do_ioctl+0x2b0/0x39c CPU: core-0: Call trace: venus_shutdown+0x98/0xfc [venus_core] venus_sys_error_handler+0x64/0x148 [venus_core] process_one_work+0x210/0x3d0 worker_thread+0x248/0x3f4 kthread+0x11c/0x12c Signed-off-by: Mansur Alisha Shaik --- drivers/media/platform/qcom/venus/core.c | 2 +- drivers/media/platform/qcom/venus/hfi.c | 5 ++++- 2 files changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/media/platform/qcom/venus/core.c b/drivers/media/platform/qcom/venus/core.c index 203c653..fe99c83 100644 --- a/drivers/media/platform/qcom/venus/core.c +++ b/drivers/media/platform/qcom/venus/core.c @@ -64,8 +64,8 @@ static void venus_sys_error_handler(struct work_struct *work) pm_runtime_get_sync(core->dev); hfi_core_deinit(core, true); - hfi_destroy(core); mutex_lock(&core->lock); + hfi_destroy(core); venus_shutdown(core); pm_runtime_put_sync(core->dev); diff --git a/drivers/media/platform/qcom/venus/hfi.c b/drivers/media/platform/qcom/venus/hfi.c index a211eb9..2eeb31f 100644 --- a/drivers/media/platform/qcom/venus/hfi.c +++ b/drivers/media/platform/qcom/venus/hfi.c @@ -195,7 +195,7 @@ EXPORT_SYMBOL_GPL(hfi_session_create); int hfi_session_init(struct venus_inst *inst, u32 pixfmt) { struct venus_core *core = inst->core; - const struct hfi_ops *ops = core->ops; + const struct hfi_ops *ops; int ret; if (inst->state != INST_UNINIT) @@ -204,10 +204,13 @@ int hfi_session_init(struct venus_inst *inst, u32 pixfmt) inst->hfi_codec = to_codec_type(pixfmt); reinit_completion(&inst->done); + mutex_lock(&core->lock); + ops = core->ops; ret = ops->session_init(inst, inst->session_type, inst->hfi_codec); if (ret) return ret; + mutex_unlock(&core->lock); ret = wait_session_msg(inst); if (ret) return ret;