Commit be760c6e authored by Xin Jiang's avatar Xin Jiang Committed by hanliyang
Browse files

x86/boot/compressed/64: Add CSV3 guest detection 

hygon inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/IAYGKY


CVE: NA

---------------------------

Check if CSV3 guest is active at boot compressed stage. It
checks HYGON hardware with CPUID 0x00000000 and bit30 of MSR
0xc0010131.

Signed-off-by: default avatarXin Jiang <jiangxin@hygon.cn>
Signed-off-by: default avatarhanliyang <hanliyang@hygon.cn>
parent c97c1d01

arch/x86/boot/compressed/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -109,6 +109,7 @@ ifdef CONFIG_X86_64 
	vmlinux-objs-$(CONFIG_AMD_MEM_ENCRYPT) += $(obj)/mem_encrypt.o

	vmlinux-objs-y += $(obj)/pgtable_64.o

	vmlinux-objs-$(CONFIG_AMD_MEM_ENCRYPT) += $(obj)/sev.o

	vmlinux-objs-$(CONFIG_HYGON_CSV) += $(obj)/csv.o

endif



vmlinux-objs-$(CONFIG_ACPI) += $(obj)/acpi.o

arch/x86/boot/compressed/csv.c

0 → 100644
+38 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-only

/*

 * Hygon CSV Support

 *

 * Copyright (C) Hygon Info Technologies Ltd.

 */



#include "misc.h"



#include <asm/csv.h>

#include <asm/cpuid.h>



static unsigned int csv3_enabled __section(".data");



void csv_set_status(void)

{

	unsigned int eax;

	unsigned int ebx;

	unsigned int ecx;

	unsigned int edx;



	eax = 0;

	native_cpuid(&eax, &ebx, &ecx, &edx);



	/* HygonGenuine */

	if (ebx == CPUID_VENDOR_HygonGenuine_ebx &&

	    ecx == CPUID_VENDOR_HygonGenuine_ecx &&

	    edx == CPUID_VENDOR_HygonGenuine_edx &&

	    sme_me_mask) {

		unsigned long low, high;



		asm volatile("rdmsr\n" : "=a" (low), "=d" (high) :

			"c" (MSR_AMD64_SEV));



		if (low & MSR_CSV3_ENABLED)

			csv3_enabled = 1;

	}

}

arch/x86/boot/compressed/csv.h

0 → 100644
+23 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0-only */

/*

 * Hygon CSV header for early boot related functions.

 *

 * Copyright (C) Hygon Info Technologies Ltd.

 *

 * Author: Liyang Han <hanliyang@hygon.cn>

 */



#ifndef BOOT_COMPRESSED_CSV_H

#define BOOT_COMPRESSED_CSV_H



#ifdef CONFIG_HYGON_CSV



void csv_set_status(void);



#else



static inline void csv_set_status(void) { }



#endif



#endif	/* BOOT_COMPRESSED_CSV_H */

arch/x86/boot/compressed/head_64.S

+10 −0
Original line number Diff line number Diff line
@@ -397,6 +397,16 @@ SYM_CODE_START(startup_64) 
	movq	%r15, %rdi

	call	sev_enable

#endif

#ifdef CONFIG_HYGON_CSV

	/*

	 * Check CSV active status. The CSV and CSV2 guest are indicated by

	 * MSR_AMD64_SEV_ENABLED_BIT and MSR_AMD64_SEV_ES_ENABLED_BIT in MSR

	 * register 0xc0010131, respectively.

	 * The CSV3 guest is indicated by MSR_CSV3_ENABLED in MSR register

	 * 0xc0010131.

	 */

	call	csv_set_status

#endif



	/* Preserve only the CR4 bits that must be preserved, and clear the rest */

	movq	%cr4, %rax

arch/x86/boot/compressed/misc.h

+1 −0
Original line number Diff line number Diff line
@@ -37,6 +37,7 @@ 
#include <asm/desc_defs.h>



#include "tdx.h"

#include "csv.h"



#define BOOT_CTYPE_H

#include <linux/acpi.h>