cmdline.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * AMD SVM-SEV command line parsing support
 *
 * Copyright (C) 2023 - 2024 Advanced Micro Devices, Inc.
 *
 * Author: Michael Roth <[email protected]>
 */

#include <linux/string.h>
#include <linux/printk.h>
#include <linux/cache.h>
#include <linux/cpufeature.h>

#include <asm/sev-common.h>

struct sev_config sev_cfg __read_mostly;

static int __init init_sev_config(char *str)
{
	char *s;

	while ((s = strsep(&str, ","))) {
		if (!strcmp(s, "debug")) {
			sev_cfg.debug = true;
			continue;
		}

		if (!strcmp(s, "nosnp")) {
			if (!cpu_feature_enabled(X86_FEATURE_HYPERVISOR)) {
				setup_clear_cpu_cap(X86_FEATURE_SEV_SNP);
				cc_platform_clear(CC_ATTR_HOST_SEV_SNP);
				continue;
			} else {
				goto warn;
			}
		}

warn:
		pr_info("SEV command-line option '%s' was not recognized\n", s);
	}

	return 1;
}
__setup("sev=", init_sev_config);