Greg,

please pull the latest x86-urgent-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
x86-urgent-for-linus

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.

Thanks,

        tglx

------------------>
Kairui Song (1):
      x86/boot: Fix kexec booting failure in the SEV bit detection code


 arch/x86/boot/compressed/mem_encrypt.S | 19 -------------------
 1 file changed, 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

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