From patchwork Fri Feb 12 22:25:41 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ben Widawsky X-Patchwork-Id: 12086193 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=-16.7 required=3.0 tests=BAYES_00, 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 77BC8C433DB for ; Fri, 12 Feb 2021 22:26:03 +0000 (UTC) Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3F4CE64E8E for ; Fri, 12 Feb 2021 22:26:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3F4CE64E8E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvdimm-bounces@lists.01.org Received: from ml01.vlan13.01.org (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 77500100EA103; Fri, 12 Feb 2021 14:26:01 -0800 (PST) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=134.134.136.100; helo=mga07.intel.com; envelope-from=ben.widawsky@intel.com; receiver= Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 9DCAE100EB82A for ; Fri, 12 Feb 2021 14:25:58 -0800 (PST) IronPort-SDR: 5ZZdWm+CpjiiVSDDN/HsIf5JLIl3j06fGCDlxw7UDakoBz6QNVg15cfshmi02ccun5W7bxvqH/ EsdwOSIDHMbA== X-IronPort-AV: E=McAfee;i="6000,8403,9893"; a="246551494" X-IronPort-AV: E=Sophos;i="5.81,174,1610438400"; d="scan'208";a="246551494" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Feb 2021 14:25:58 -0800 IronPort-SDR: r6YZYqlYIvTty3eB86Tikw6LVEBlc0F4Xyl9ql4Ojc9awVKYH45lxFwkZ9J4lMXXmvybRrHcyb VJiJekJ3ko7A== X-IronPort-AV: E=Sophos;i="5.81,174,1610438400"; d="scan'208";a="587605404" Received: from smandal1-mobl2.amr.corp.intel.com (HELO bwidawsk-mobl5.local) ([10.252.133.121]) by fmsmga006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Feb 2021 14:25:57 -0800 From: Ben Widawsky To: linux-cxl@vger.kernel.org Subject: [RFC PATCH 9/9] cxl/mem: Add payload dumping for debug Date: Fri, 12 Feb 2021 14:25:41 -0800 Message-Id: <20210212222541.2123505-10-ben.widawsky@intel.com> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210212222541.2123505-1-ben.widawsky@intel.com> References: <20210212222541.2123505-1-ben.widawsky@intel.com> MIME-Version: 1.0 Message-ID-Hash: 5ZZOYHPVWISS4XX2IUT3YGYOSIZROYBE X-Message-ID-Hash: 5ZZOYHPVWISS4XX2IUT3YGYOSIZROYBE X-MailFrom: ben.widawsky@intel.com X-Mailman-Rule-Hits: nonmember-moderation X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation CC: Ben Widawsky , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-nvdimm@lists.01.org, linux-pci@vger.kernel.org, Bjorn Helgaas , Chris Browy , Christoph Hellwig , David Hildenbrand , David Rientjes , Jon Masters , Jonathan Cameron , Rafael Wysocki , Randy Dunlap , "John Groves (jgroves)" , "Kelley, Sean V" X-Mailman-Version: 3.1.1 Precedence: list List-Id: "Linux-nvdimm developer list." Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: It's often useful in debug scenarios to see what the hardware has dumped out. As it stands today, any device error will result in the payload not being copied out, so there is no way to triage commands which weren't expected to fail (and sometimes the payload may have that information). The functionality is protected by normal kernel security mechanisms as well as a CONFIG option in the CXL driver. This was extracted from the original version of the CXL enabling patch series. Signed-off-by: Ben Widawsky --- drivers/cxl/Kconfig | 13 +++++++++++++ drivers/cxl/mem.c | 8 ++++++++ 2 files changed, 21 insertions(+) diff --git a/drivers/cxl/Kconfig b/drivers/cxl/Kconfig index 97dc4d751651..3eec9276e586 100644 --- a/drivers/cxl/Kconfig +++ b/drivers/cxl/Kconfig @@ -50,4 +50,17 @@ config CXL_MEM_RAW_COMMANDS potential impact to memory currently in use by the kernel. If developing CXL hardware or the driver say Y, otherwise say N. + +config CXL_MEM_INSECURE_DEBUG + bool "CXL.mem debugging" + depends on CXL_MEM + help + Enable debug of all CXL command payloads. + + Some CXL devices and controllers support encryption and other + security features. The payloads for the commands that enable + those features may contain sensitive clear-text security + material. Disable debug of those command payloads by default. + If you are a kernel developer actively working on CXL + security enabling say Y, otherwise say N. endif diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c index 3bca8451348a..09c11935b824 100644 --- a/drivers/cxl/mem.c +++ b/drivers/cxl/mem.c @@ -341,6 +341,14 @@ static int __cxl_mem_mbox_send_cmd(struct cxl_mem *cxlm, /* #5 */ rc = cxl_mem_wait_for_doorbell(cxlm); + + if (!cxl_is_security_command(mbox_cmd->opcode) || + IS_ENABLED(CONFIG_CXL_MEM_INSECURE_DEBUG)) { + print_hex_dump_debug("Payload ", DUMP_PREFIX_OFFSET, 16, 1, + mbox_cmd->payload_in, mbox_cmd->size_in, + true); + } + if (rc == -ETIMEDOUT) { cxl_mem_mbox_timeout(cxlm, mbox_cmd); return rc;