linux/arch/x86/boot/compressed/mem_encrypt.S
Jiri Slaby b8c3f9b554 x86/boot: Annotate data appropriately
Use the new SYM_DATA, SYM_DATA_START, and SYM_DATA_END* macros for data,
so that the data in the object file look sane:

  Value   Size Type    Bind   Vis      Ndx Name
    0000    10 OBJECT  GLOBAL DEFAULT    3 efi32_boot_gdt
    000a    10 OBJECT  LOCAL  DEFAULT    3 save_gdt
    0014     8 OBJECT  LOCAL  DEFAULT    3 func_rt_ptr
    001c    48 OBJECT  GLOBAL DEFAULT    3 efi_gdt64
    004c     0 OBJECT  LOCAL  DEFAULT    3 efi_gdt64_end

    0000    48 OBJECT  LOCAL  DEFAULT    3 gdt
    0030     0 OBJECT  LOCAL  DEFAULT    3 gdt_end
    0030     8 OBJECT  LOCAL  DEFAULT    3 efi_config
    0038    49 OBJECT  GLOBAL DEFAULT    3 efi32_config
    0069    49 OBJECT  GLOBAL DEFAULT    3 efi64_config

All have correct size and type now.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Allison Randal <allison@lohutok.net>
Cc: Cao jin <caoj.fnst@cn.fujitsu.com>
Cc: Enrico Weigelt <info@metux.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: linux-arch@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Huang <wei@redhat.com>
Cc: x86-ml <x86@kernel.org>
Cc: Xiaoyao Li <xiaoyao.li@linux.intel.com>
Link: https://lkml.kernel.org/r/20191011115108.12392-13-jslaby@suse.cz
2019-10-18 10:43:26 +02:00

101 lines
1.9 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* AMD Memory Encryption Support
*
* Copyright (C) 2017 Advanced Micro Devices, Inc.
*
* Author: Tom Lendacky <thomas.lendacky@amd.com>
*/
#include <linux/linkage.h>
#include <asm/processor-flags.h>
#include <asm/msr.h>
#include <asm/asm-offsets.h>
.text
.code32
ENTRY(get_sev_encryption_bit)
xor %eax, %eax
#ifdef CONFIG_AMD_MEM_ENCRYPT
push %ebx
push %ecx
push %edx
/* Check if running under a hypervisor */
movl $1, %eax
cpuid
bt $31, %ecx /* Check the hypervisor bit */
jnc .Lno_sev
movl $0x80000000, %eax /* CPUID to check the highest leaf */
cpuid
cmpl $0x8000001f, %eax /* See if 0x8000001f is available */
jb .Lno_sev
/*
* Check for the SEV feature:
* CPUID Fn8000_001F[EAX] - Bit 1
* CPUID Fn8000_001F[EBX] - Bits 5:0
* Pagetable bit position used to indicate encryption
*/
movl $0x8000001f, %eax
cpuid
bt $1, %eax /* Check if SEV is available */
jnc .Lno_sev
movl $MSR_AMD64_SEV, %ecx /* Read the SEV MSR */
rdmsr
bt $MSR_AMD64_SEV_ENABLED_BIT, %eax /* Check if SEV is active */
jnc .Lno_sev
movl %ebx, %eax
andl $0x3f, %eax /* Return the encryption bit location */
jmp .Lsev_exit
.Lno_sev:
xor %eax, %eax
.Lsev_exit:
pop %edx
pop %ecx
pop %ebx
#endif /* CONFIG_AMD_MEM_ENCRYPT */
ret
ENDPROC(get_sev_encryption_bit)
.code64
ENTRY(set_sev_encryption_mask)
#ifdef CONFIG_AMD_MEM_ENCRYPT
push %rbp
push %rdx
movq %rsp, %rbp /* Save current stack pointer */
call get_sev_encryption_bit /* Get the encryption bit position */
testl %eax, %eax
jz .Lno_sev_mask
bts %rax, sme_me_mask(%rip) /* Create the encryption mask */
.Lno_sev_mask:
movq %rbp, %rsp /* Restore original stack pointer */
pop %rdx
pop %rbp
#endif
xor %rax, %rax
ret
ENDPROC(set_sev_encryption_mask)
.data
#ifdef CONFIG_AMD_MEM_ENCRYPT
.balign 8
SYM_DATA(sme_me_mask, .quad 0)
#endif