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Diffstat (limited to 'arch/x86/mm/mem_encrypt_identity.c')
-rw-r--r--arch/x86/mm/mem_encrypt_identity.c32
1 files changed, 3 insertions, 29 deletions
diff --git a/arch/x86/mm/mem_encrypt_identity.c b/arch/x86/mm/mem_encrypt_identity.c
index 0166ab1780cc..d210c7fc8fa2 100644
--- a/arch/x86/mm/mem_encrypt_identity.c
+++ b/arch/x86/mm/mem_encrypt_identity.c
@@ -43,7 +43,6 @@
#include <asm/setup.h>
#include <asm/sections.h>
-#include <asm/cmdline.h>
#include <asm/coco.h>
#include <asm/sev.h>
@@ -95,9 +94,6 @@ struct sme_populate_pgd_data {
*/
static char sme_workarea[2 * PMD_SIZE] __section(".init.scratch");
-static char sme_cmdline_arg[] __initdata = "mem_encrypt";
-static char sme_cmdline_on[] __initdata = "on";
-
static void __init sme_clear_pgd(struct sme_populate_pgd_data *ppd)
{
unsigned long pgd_start, pgd_end, pgd_size;
@@ -504,11 +500,9 @@ void __init sme_encrypt_kernel(struct boot_params *bp)
void __init sme_enable(struct boot_params *bp)
{
- const char *cmdline_ptr, *cmdline_arg, *cmdline_on;
unsigned int eax, ebx, ecx, edx;
unsigned long feature_mask;
unsigned long me_mask;
- char buffer[16];
bool snp;
u64 msr;
@@ -551,6 +545,9 @@ void __init sme_enable(struct boot_params *bp)
/* Check if memory encryption is enabled */
if (feature_mask == AMD_SME_BIT) {
+ if (!(bp->hdr.xloadflags & XLF_MEM_ENCRYPTION))
+ return;
+
/*
* No SME if Hypervisor bit is set. This check is here to
* prevent a guest from trying to enable SME. For running as a
@@ -570,31 +567,8 @@ void __init sme_enable(struct boot_params *bp)
msr = __rdmsr(MSR_AMD64_SYSCFG);
if (!(msr & MSR_AMD64_SYSCFG_MEM_ENCRYPT))
return;
- } else {
- /* SEV state cannot be controlled by a command line option */
- goto out;
}
- /*
- * Fixups have not been applied to phys_base yet and we're running
- * identity mapped, so we must obtain the address to the SME command
- * line argument data using rip-relative addressing.
- */
- asm ("lea sme_cmdline_arg(%%rip), %0"
- : "=r" (cmdline_arg)
- : "p" (sme_cmdline_arg));
- asm ("lea sme_cmdline_on(%%rip), %0"
- : "=r" (cmdline_on)
- : "p" (sme_cmdline_on));
-
- cmdline_ptr = (const char *)((u64)bp->hdr.cmd_line_ptr |
- ((u64)bp->ext_cmd_line_ptr << 32));
-
- if (cmdline_find_option(cmdline_ptr, cmdline_arg, buffer, sizeof(buffer)) < 0 ||
- strncmp(buffer, cmdline_on, sizeof(buffer)))
- return;
-
-out:
RIP_REL_REF(sme_me_mask) = me_mask;
physical_mask &= ~me_mask;
cc_vendor = CC_VENDOR_AMD;