From mboxrd@z Thu Jan 1 00:00:00 1970 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,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 62DD0C433E0 for ; Mon, 3 Aug 2020 20:42:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 75920207DF for ; Mon, 3 Aug 2020 20:42:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728490AbgHCUmK (ORCPT ); Mon, 3 Aug 2020 16:42:10 -0400 Received: from mga05.intel.com ([192.55.52.43]:12119 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726693AbgHCUmJ (ORCPT ); Mon, 3 Aug 2020 16:42:09 -0400 IronPort-SDR: c38/PJc6fdxU/aC0Y6mS49sv4QoxnHtZcm9w9XRybcABrmrIxwD4GW3IySjXO0UJag4l9MCs/3 bZ6MT4lR0hGw== X-IronPort-AV: E=McAfee;i="6000,8403,9702"; a="237059833" X-IronPort-AV: E=Sophos;i="5.75,431,1589266800"; d="scan'208";a="237059833" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Aug 2020 13:42:08 -0700 IronPort-SDR: G8qehCHuJl7G+oYeLcNmtNncs+SV1quOrUt0k6EZCvNZVKFommktmxwqbgieIgWw+BfsL8TLcb 7N/nz6Urovhg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,431,1589266800"; d="scan'208";a="314944197" Received: from djiang5-mobl1.amr.corp.intel.com (HELO [10.255.79.119]) ([10.255.79.119]) by fmsmga004.fm.intel.com with ESMTP; 03 Aug 2020 13:42:08 -0700 Subject: Re: [PATCH 2/2] libnvdimm/security: ensure sysfs poll thread woke up and fetch updated attr To: Jane Chu , dan.j.williams@intel.com, vishal.l.verma@intel.com, ira.weiny@intel.com, jmoyer@redhat.com, linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org References: <1595606959-8516-1-git-send-email-jane.chu@oracle.com> <1595606959-8516-2-git-send-email-jane.chu@oracle.com> From: Dave Jiang Message-ID: Date: Mon, 3 Aug 2020 13:42:08 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <1595606959-8516-2-git-send-email-jane.chu@oracle.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/24/2020 9:09 AM, Jane Chu wrote: > commit 7d988097c546 ("acpi/nfit, libnvdimm/security: Add security DSM overwrite support") > adds a sysfs_notify_dirent() to wake up userspace poll thread when the "overwrite" > operation has completed. But the notification is issued before the internal > dimm security state and flags have been updated, so the userspace poll thread > wakes up and fetches the not-yet-updated attr and falls back to sleep, forever. > But if user from another terminal issue "ndctl wait-overwrite nmemX" again, > the command returns instantly. > > Cc: Dave Jiang > Cc: Dan Williams > Fixes: 7d988097c546 ("acpi/nfit, libnvdimm/security: Add security DSM overwrite support") > Signed-off-by: Jane Chu Reviewed-by: Dave Jiang > --- > drivers/nvdimm/security.c | 11 ++++++++--- > 1 file changed, 8 insertions(+), 3 deletions(-) > > diff --git a/drivers/nvdimm/security.c b/drivers/nvdimm/security.c > index 8f3971c..4b80150 100644 > --- a/drivers/nvdimm/security.c > +++ b/drivers/nvdimm/security.c > @@ -450,14 +450,19 @@ void __nvdimm_security_overwrite_query(struct nvdimm *nvdimm) > else > dev_dbg(&nvdimm->dev, "overwrite completed\n"); > > - if (nvdimm->sec.overwrite_state) > - sysfs_notify_dirent(nvdimm->sec.overwrite_state); > + /* > + * Mark the overwrite work done and update dimm security flags, > + * then send a sysfs event notification to wake up userspace > + * poll threads to picked up the changed state. > + */ > nvdimm->sec.overwrite_tmo = 0; > clear_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags); > clear_bit(NDD_WORK_PENDING, &nvdimm->flags); > - put_device(&nvdimm->dev); > nvdimm->sec.flags = nvdimm_security_flags(nvdimm, NVDIMM_USER); > nvdimm->sec.ext_flags = nvdimm_security_flags(nvdimm, NVDIMM_MASTER); > + if (nvdimm->sec.overwrite_state) > + sysfs_notify_dirent(nvdimm->sec.overwrite_state); > + put_device(&nvdimm->dev); > } > > void nvdimm_security_overwrite_query(struct work_struct *work) >