From patchwork Thu Mar 12 15:53:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Berger X-Patchwork-Id: 11434731 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 860CD161F for ; Thu, 12 Mar 2020 15:55:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6F1FA206BE for ; Thu, 12 Mar 2020 15:55:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727859AbgCLPzw (ORCPT ); Thu, 12 Mar 2020 11:55:52 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:10030 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726395AbgCLPzw (ORCPT ); Thu, 12 Mar 2020 11:55:52 -0400 Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 02CFqO5c095978; Thu, 12 Mar 2020 11:55:47 -0400 Received: from ppma01dal.us.ibm.com (83.d6.3fa9.ip4.static.sl-reverse.com [169.63.214.131]) by mx0b-001b2d01.pphosted.com with ESMTP id 2yqpyau4fc-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 12 Mar 2020 11:55:46 -0400 Received: from pps.filterd (ppma01dal.us.ibm.com [127.0.0.1]) by ppma01dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 02CFlCUV030268; Thu, 12 Mar 2020 15:53:34 GMT Received: from b01cxnp22036.gho.pok.ibm.com (b01cxnp22036.gho.pok.ibm.com [9.57.198.26]) by ppma01dal.us.ibm.com with ESMTP id 2ypjxrhgch-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 12 Mar 2020 15:53:34 +0000 Received: from b01ledav005.gho.pok.ibm.com (b01ledav005.gho.pok.ibm.com [9.57.199.110]) by b01cxnp22036.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 02CFrXKH13632072 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 12 Mar 2020 15:53:33 GMT Received: from b01ledav005.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 46829AE060; Thu, 12 Mar 2020 15:53:33 +0000 (GMT) Received: from b01ledav005.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2DDCAAE05C; Thu, 12 Mar 2020 15:53:33 +0000 (GMT) Received: from sbct-3.pok.ibm.com (unknown [9.47.158.153]) by b01ledav005.gho.pok.ibm.com (Postfix) with ESMTP; Thu, 12 Mar 2020 15:53:33 +0000 (GMT) From: Stefan Berger To: jarkko.sakkinen@linux.intel.com, linux-integrity@vger.kernel.org Cc: aik@ozlabs.ru, david@gibson.dropbear.id.au, linux-kernel@vger.kernel.org, nayna@linux.vnet.ibm.com, gcwilson@linux.ibm.com, jgg@ziepe.ca, Stefan Berger , Nayna Jain Subject: [PATCH v7 2/3] tpm: ibmvtpm: Wait for buffer to be set before proceeding Date: Thu, 12 Mar 2020 11:53:31 -0400 Message-Id: <20200312155332.671464-3-stefanb@linux.vnet.ibm.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200312155332.671464-1-stefanb@linux.vnet.ibm.com> References: <20200312155332.671464-1-stefanb@linux.vnet.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-03-12_07:2020-03-11,2020-03-12 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 spamscore=0 suspectscore=0 impostorscore=0 malwarescore=0 mlxlogscore=999 adultscore=0 phishscore=0 mlxscore=0 bulkscore=0 lowpriorityscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2003120082 Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: Stefan Berger Synchronize with the results from the CRQs before continuing with the initialization. This avoids trying to send TPM commands while the rtce buffer has not been allocated, yet. This patch fixes an existing race condition that may occurr if the hypervisor does not quickly respond to the VTPM_GET_RTCE_BUFFER_SIZE request sent during initialization and therefore the ibmvtpm->rtce_buf has not been allocated at the time the first TPM command is sent. Fixes: 132f76294744 ("Add new device driver to support IBM vTPM") Signed-off-by: Stefan Berger Acked-by: Nayna Jain Tested-by: Nayna Jain Reviewed-by: Jarkko Sakkinen --- drivers/char/tpm/tpm_ibmvtpm.c | 9 +++++++++ drivers/char/tpm/tpm_ibmvtpm.h | 1 + 2 files changed, 10 insertions(+) diff --git a/drivers/char/tpm/tpm_ibmvtpm.c b/drivers/char/tpm/tpm_ibmvtpm.c index 78cc52690177..cfe40e7b1ba4 100644 --- a/drivers/char/tpm/tpm_ibmvtpm.c +++ b/drivers/char/tpm/tpm_ibmvtpm.c @@ -571,6 +571,7 @@ static irqreturn_t ibmvtpm_interrupt(int irq, void *vtpm_instance) */ while ((crq = ibmvtpm_crq_get_next(ibmvtpm)) != NULL) { ibmvtpm_crq_process(crq, ibmvtpm); + wake_up_interruptible(&ibmvtpm->crq_queue.wq); crq->valid = 0; smp_wmb(); } @@ -618,6 +619,7 @@ static int tpm_ibmvtpm_probe(struct vio_dev *vio_dev, } crq_q->num_entry = CRQ_RES_BUF_SIZE / sizeof(*crq_q->crq_addr); + init_waitqueue_head(&crq_q->wq); ibmvtpm->crq_dma_handle = dma_map_single(dev, crq_q->crq_addr, CRQ_RES_BUF_SIZE, DMA_BIDIRECTIONAL); @@ -670,6 +672,13 @@ static int tpm_ibmvtpm_probe(struct vio_dev *vio_dev, if (rc) goto init_irq_cleanup; + if (!wait_event_timeout(ibmvtpm->crq_queue.wq, + ibmvtpm->rtce_buf != NULL, + HZ)) { + dev_err(dev, "CRQ response timed out\n"); + goto init_irq_cleanup; + } + return tpm_chip_register(chip); init_irq_cleanup: do { diff --git a/drivers/char/tpm/tpm_ibmvtpm.h b/drivers/char/tpm/tpm_ibmvtpm.h index 7983f1a33267..b92aa7d3e93e 100644 --- a/drivers/char/tpm/tpm_ibmvtpm.h +++ b/drivers/char/tpm/tpm_ibmvtpm.h @@ -26,6 +26,7 @@ struct ibmvtpm_crq_queue { struct ibmvtpm_crq *crq_addr; u32 index; u32 num_entry; + wait_queue_head_t wq; }; struct ibmvtpm_dev {