Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Thomas writes:
  "A single fix for the AMD memory encryption boot code so it does not
   read random garbage instead of the cached encryption bit when a kexec
   kernel is allocated above the 32bit address limit."

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Fix kexec booting failure in the SEV bit detection code

1 files changed, 0 insertions, 19 deletions

diff --git a/arch/x86/boot/compressed/mem_encrypt.S b/arch/x86/boot/compressed/mem_encrypt.S
index eaa843a52907..a480356e0ed8 100644
--- a/arch/x86/boot/compressed/mem_encrypt.S
+++ b/arch/x86/boot/compressed/mem_encrypt.S
@@ -25,20 +25,6 @@ ENTRY(get_sev_encryption_bit)
         push    %ebx
         push    %ecx
         push    %edx
-        push    %edi
-
-        /*
-         * RIP-relative addressing is needed to access the encryption bit
-         * variable. Since we are running in 32-bit mode we need this call/pop
-         * sequence to get the proper relative addressing.
-         */
-        call    1f
-1:      popl    %edi
-        subl    $1b, %edi
-
-        movl    enc_bit(%edi), %eax
-        cmpl    $0, %eax
-        jge     .Lsev_exit
 
         /* Check if running under a hypervisor */
         movl    $1, %eax
@@ -69,15 +55,12 @@ ENTRY(get_sev_encryption_bit)
 
         movl    %ebx, %eax
         andl    $0x3f, %eax             /* Return the encryption bit location */
-        movl    %eax, enc_bit(%edi)
         jmp     .Lsev_exit
 
 .Lno_sev:
         xor     %eax, %eax
-        movl    %eax, enc_bit(%edi)
 
 .Lsev_exit:
-        pop     %edi
         pop     %edx
         pop     %ecx
         pop     %ebx
@@ -113,8 +96,6 @@ ENTRY(set_sev_encryption_mask)
 ENDPROC(set_sev_encryption_mask)
 
         .data
-enc_bit:
-        .int    0xffffffff
 
 #ifdef CONFIG_AMD_MEM_ENCRYPT
         .balign 8