Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752370AbdFLOWI (ORCPT ); Mon, 12 Jun 2017 10:22:08 -0400 Received: from mx2.suse.de ([195.135.220.15]:45101 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752247AbdFLOWG (ORCPT ); Mon, 12 Jun 2017 10:22:06 -0400 From: Juergen Gross To: linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org Cc: boris.ostrovsky@oracle.com, gregkh@linuxfoundation.org, Juergen Gross Subject: [PATCH v3 4/4] xen: add sysfs node for hypervisor build id Date: Mon, 12 Jun 2017 16:21:50 +0200 Message-Id: <20170612142150.15283-5-jgross@suse.com> X-Mailer: git-send-email 2.12.3 In-Reply-To: <20170612142150.15283-1-jgross@suse.com> References: <20170612142150.15283-1-jgross@suse.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2542 Lines: 82 For support of Xen hypervisor live patching the hypervisor build id is needed. Add a node /sys/hypervisor/properties/buildid containing the information. Signed-off-by: Juergen Gross --- Documentation/ABI/testing/sysfs-hypervisor-xen | 11 +++++++++- drivers/xen/sys-hypervisor.c | 29 ++++++++++++++++++++++++++ 2 files changed, 39 insertions(+), 1 deletion(-) diff --git a/Documentation/ABI/testing/sysfs-hypervisor-xen b/Documentation/ABI/testing/sysfs-hypervisor-xen index c0edb3fdd6eb..53b7b2ea7515 100644 --- a/Documentation/ABI/testing/sysfs-hypervisor-xen +++ b/Documentation/ABI/testing/sysfs-hypervisor-xen @@ -1,5 +1,5 @@ What: /sys/hypervisor/guest_type -Date: May 2017 +Date: June 2017 KernelVersion: 4.13 Contact: xen-devel@lists.xenproject.org Description: If running under Xen: @@ -32,3 +32,12 @@ Description: If running under Xen: Describes Xen PMU features (as an integer). A set bit indicates that the corresponding feature is enabled. See include/xen/interface/xenpmu.h for available features + +What: /sys/hypervisor/properties/buildid +Date: June 2017 +KernelVersion: 4.13 +Contact: xen-devel@lists.xenproject.org +Description: If running under Xen: + Build id of the hypervisor, needed for hypervisor live patching. + Might return "" in case of special security settings + in the hypervisor. diff --git a/drivers/xen/sys-hypervisor.c b/drivers/xen/sys-hypervisor.c index d641e9970d5d..92307636ed54 100644 --- a/drivers/xen/sys-hypervisor.c +++ b/drivers/xen/sys-hypervisor.c @@ -339,12 +339,41 @@ static ssize_t features_show(struct hyp_sysfs_attr *attr, char *buffer) HYPERVISOR_ATTR_RO(features); +static ssize_t buildid_show(struct hyp_sysfs_attr *attr, char *buffer) +{ + ssize_t ret; + struct xen_build_id dummy; + struct xen_build_id *buildid; + + dummy.len = 0; + ret = HYPERVISOR_xen_version(XENVER_get_features, &dummy); + if (ret < 0) { + if (ret == -EPERM) + ret = sprintf(buffer, ""); + return ret; + } + + buildid = kmalloc(sizeof(*buildid) + dummy.len, GFP_KERNEL); + if (!buildid) + return -ENOMEM; + + ret = HYPERVISOR_xen_version(XENVER_get_features, buildid); + if (ret > 0) + ret = sprintf(buffer, "%s", buildid->buf); + kfree(buildid); + + return ret; +} + +HYPERVISOR_ATTR_RO(buildid); + static struct attribute *xen_properties_attrs[] = { &capabilities_attr.attr, &changeset_attr.attr, &virtual_start_attr.attr, &pagesize_attr.attr, &features_attr.attr, + &buildid_attr.attr, NULL }; -- 2.12.3