From patchwork Fri Aug 13 15:07:20 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 497016 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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 5B9EAC4338F for ; Fri, 13 Aug 2021 15:15:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 47337610CF for ; Fri, 13 Aug 2021 15:15:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241852AbhHMPQM (ORCPT ); Fri, 13 Aug 2021 11:16:12 -0400 Received: from mail.kernel.org ([198.145.29.99]:59108 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242703AbhHMPOl (ORCPT ); Fri, 13 Aug 2021 11:14:41 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 78A6E610F7; Fri, 13 Aug 2021 15:14:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1628867655; bh=E7wxtjAb81PF0LND7bzdoKazKry0KsHM2b7YkjrrFg8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WeXMXEg6qJiSPQxPU0ivTV2A9/08YxVvjPT63Hg4LygMNBDcUtKg/8YK3lYu/Bwy+ Zv++NsxJaYLfBcXvPY5ridZBRRWlsuROerHOpW++P6ysSYdiK+Q35MgBoMr7GQLWwu vrFZ2Xnce8wgLXjkga9DQFWfL/y9gi7yuC4KvPuc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Allen Pais , Tyler Hicks , Sumit Garg , Florian Fainelli , Jens Wiklander , Sasha Levin Subject: [PATCH 5.10 03/19] firmware: tee_bnxt: Release TEE shm, session, and context during kexec Date: Fri, 13 Aug 2021 17:07:20 +0200 Message-Id: <20210813150522.739650240@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210813150522.623322501@linuxfoundation.org> References: <20210813150522.623322501@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Allen Pais [ Upstream commit 914ab19e471d8fb535ed50dff108b0a615f3c2d8 ] Implement a .shutdown hook that will be called during a kexec operation so that the TEE shared memory, session, and context that were set up during .probe can be properly freed/closed. Additionally, don't use dma-buf backed shared memory for the fw_shm_pool. dma-buf backed shared memory cannot be reliably freed and unregistered during a kexec operation even when tee_shm_free() is called on the shm from a .shutdown hook. The problem occurs because dma_buf_put() calls fput() which then uses task_work_add(), with the TWA_RESUME parameter, to queue tee_shm_release() to be called before the current task returns to user mode. However, the current task never returns to user mode before the kexec completes so the memory is never freed nor unregistered. Use tee_shm_alloc_kernel_buf() to avoid dma-buf backed shared memory allocation so that tee_shm_free() can directly call tee_shm_release(). This will ensure that the shm can be freed and unregistered during a kexec operation. Fixes: 246880958ac9 ("firmware: broadcom: add OP-TEE based BNXT f/w manager") Cc: stable@vger.kernel.org Signed-off-by: Allen Pais Co-developed-by: Tyler Hicks Signed-off-by: Tyler Hicks Reviewed-by: Sumit Garg Acked-by: Florian Fainelli Signed-off-by: Jens Wiklander Signed-off-by: Sasha Levin --- drivers/firmware/broadcom/tee_bnxt_fw.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) --- a/drivers/firmware/broadcom/tee_bnxt_fw.c +++ b/drivers/firmware/broadcom/tee_bnxt_fw.c @@ -212,10 +212,9 @@ static int tee_bnxt_fw_probe(struct devi pvt_data.dev = dev; - fw_shm_pool = tee_shm_alloc(pvt_data.ctx, MAX_SHM_MEM_SZ, - TEE_SHM_MAPPED | TEE_SHM_DMA_BUF); + fw_shm_pool = tee_shm_alloc_kernel_buf(pvt_data.ctx, MAX_SHM_MEM_SZ); if (IS_ERR(fw_shm_pool)) { - dev_err(pvt_data.dev, "tee_shm_alloc failed\n"); + dev_err(pvt_data.dev, "tee_shm_alloc_kernel_buf failed\n"); err = PTR_ERR(fw_shm_pool); goto out_sess; } @@ -242,6 +241,14 @@ static int tee_bnxt_fw_remove(struct dev return 0; } +static void tee_bnxt_fw_shutdown(struct device *dev) +{ + tee_shm_free(pvt_data.fw_shm_pool); + tee_client_close_session(pvt_data.ctx, pvt_data.session_id); + tee_client_close_context(pvt_data.ctx); + pvt_data.ctx = NULL; +} + static const struct tee_client_device_id tee_bnxt_fw_id_table[] = { {UUID_INIT(0x6272636D, 0x2019, 0x0716, 0x42, 0x43, 0x4D, 0x5F, 0x53, 0x43, 0x48, 0x49)}, @@ -257,6 +264,7 @@ static struct tee_client_driver tee_bnxt .bus = &tee_bus_type, .probe = tee_bnxt_fw_probe, .remove = tee_bnxt_fw_remove, + .shutdown = tee_bnxt_fw_shutdown, }, };