Received-SPF: pass (google.com: domain of linux-kernel+bounces-118107-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) client-ip=147.75.199.223;
Received-SPF: Pass (protection.outlook.com: domain of amd.com designates
 165.204.84.17 as permitted sender) receiver=protection.outlook.com;
 client-ip=165.204.84.17; helo=SATLEXMB04.amd.com; pr=C
From: Tom Lendacky <thomas.lendacky@amd.com>
To: <linux-kernel@vger.kernel.org>, <x86@kernel.org>,
	<linux-coco@lists.linux.dev>, <svsm-devel@coconut-svsm.dev>
CC: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
	Borislav Petkov <bp@alien8.de>, Dave Hansen <dave.hansen@linux.intel.com>,
	"H. Peter Anvin" <hpa@zytor.com>, Andy Lutomirski <luto@kernel.org>, "Peter
 Zijlstra" <peterz@infradead.org>, Dan Williams <dan.j.williams@intel.com>,
	Michael Roth <michael.roth@amd.com>, Ashish Kalra <ashish.kalra@amd.com>
Subject: [PATCH v3 10/14] configfs-tsm: Allow the privlevel_floor attribute to be updated
Date: Mon, 25 Mar 2024 17:26:29 -0500
Message-ID: <bb088b1409283cd323515138feda224759a247ec.1711405593.git.thomas.lendacky@amd.com>
In-Reply-To: <cover.1711405593.git.thomas.lendacky@amd.com>
References: <cover.1711405593.git.thomas.lendacky@amd.com>
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Content-Type: text/plain
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Mar 2024 22:27:55.5091
 (UTC)
X-MS-Exchange-CrossTenant-Network-Message-Id: 3a2d899d-20de-468e-c910-08dc4d1ad153
X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d
X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[SATLEXMB04.amd.com]
X-MS-Exchange-CrossTenant-AuthSource:
	SJ1PEPF00001CDD.namprd05.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Anonymous
X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem
X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR12MB8852

With the introduction of an SVSM, Linux will be running at a non-zero
VMPL. Any request for an attestation report at a higher priviledge VMPL
than what Linux is currently running will result in an error. Allow for
the privlevel_floor attribute to be updated dynamically so that the
attribute may be set dynamically.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 drivers/virt/coco/sev-guest/sev-guest.c | 5 ++++-
 include/linux/tsm.h                     | 2 +-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/virt/coco/sev-guest/sev-guest.c b/drivers/virt/coco/sev-guest/sev-guest.c
index 1ff897913bf4..bba6531cb606 100644
--- a/drivers/virt/coco/sev-guest/sev-guest.c
+++ b/drivers/virt/coco/sev-guest/sev-guest.c
@@ -885,7 +885,7 @@ static int sev_report_new(struct tsm_report *report, void *data)
 	return 0;
 }
 
-static const struct tsm_ops sev_tsm_ops = {
+static struct tsm_ops sev_tsm_ops = {
 	.name = KBUILD_MODNAME,
 	.report_new = sev_report_new,
 };
@@ -972,6 +972,9 @@ static int __init sev_guest_probe(struct platform_device *pdev)
 	snp_dev->input.resp_gpa = __pa(snp_dev->response);
 	snp_dev->input.data_gpa = __pa(snp_dev->certs_data);
 
+	/* Set the privlevel_floor attribute based on the current VMPL */
+	sev_tsm_ops.privlevel_floor = snp_get_vmpl();
+
 	ret = tsm_register(&sev_tsm_ops, snp_dev, &tsm_report_extra_type);
 	if (ret)
 		goto e_free_cert_data;
diff --git a/include/linux/tsm.h b/include/linux/tsm.h
index de8324a2223c..50c5769657d8 100644
--- a/include/linux/tsm.h
+++ b/include/linux/tsm.h
@@ -54,7 +54,7 @@ struct tsm_report {
  */
 struct tsm_ops {
 	const char *name;
-	const unsigned int privlevel_floor;
+	unsigned int privlevel_floor;
 	int (*report_new)(struct tsm_report *report, void *data);
 };
 
-- 
2.43.2