1 files changed, 19 insertions, 15 deletions

diff --git a/arch/x86/entry/calling.h b/arch/x86/entry/calling.h
index dce7092ab24a..be63330c5511 100644
--- a/arch/x86/entry/calling.h
+++ b/arch/x86/entry/calling.h
@@ -97,7 +97,7 @@ For 32-bit we have the following conventions - kernel is built with
 
 #define SIZEOF_PTREGS   21*8
 
-.macro PUSH_AND_CLEAR_REGS rdx=%rdx rax=%rax
+.macro PUSH_AND_CLEAR_REGS rdx=%rdx rax=%rax save_ret=0
         /*
          * Push registers and sanitize registers of values that a
          * speculation attack might otherwise want to exploit. The
@@ -105,32 +105,41 @@ For 32-bit we have the following conventions - kernel is built with
          * could be put to use in a speculative execution gadget.
          * Interleave XOR with PUSH for better uop scheduling:
          */
+        .if \save_ret
+        pushq   %rsi            /* pt_regs->si */
+        movq    8(%rsp), %rsi   /* temporarily store the return address in %rsi */
+        movq    %rdi, 8(%rsp)   /* pt_regs->di (overwriting original return address) */
+        .else
         pushq   %rdi            /* pt_regs->di */
         pushq   %rsi            /* pt_regs->si */
+        .endif
         pushq   \rdx            /* pt_regs->dx */
         pushq   %rcx            /* pt_regs->cx */
         pushq   \rax            /* pt_regs->ax */
         pushq   %r8             /* pt_regs->r8 */
-        xorq    %r8, %r8        /* nospec   r8 */
+        xorl    %r8d, %r8d      /* nospec   r8 */
         pushq   %r9             /* pt_regs->r9 */
-        xorq    %r9, %r9        /* nospec   r9 */
+        xorl    %r9d, %r9d      /* nospec   r9 */
         pushq   %r10            /* pt_regs->r10 */
-        xorq    %r10, %r10      /* nospec   r10 */
+        xorl    %r10d, %r10d    /* nospec   r10 */
         pushq   %r11            /* pt_regs->r11 */
-        xorq    %r11, %r11      /* nospec   r11*/
+        xorl    %r11d, %r11d    /* nospec   r11*/
         pushq   %rbx            /* pt_regs->rbx */
         xorl    %ebx, %ebx      /* nospec   rbx*/
         pushq   %rbp            /* pt_regs->rbp */
         xorl    %ebp, %ebp      /* nospec   rbp*/
         pushq   %r12            /* pt_regs->r12 */
-        xorq    %r12, %r12      /* nospec   r12*/
+        xorl    %r12d, %r12d    /* nospec   r12*/
         pushq   %r13            /* pt_regs->r13 */
-        xorq    %r13, %r13      /* nospec   r13*/
+        xorl    %r13d, %r13d    /* nospec   r13*/
         pushq   %r14            /* pt_regs->r14 */
-        xorq    %r14, %r14      /* nospec   r14*/
+        xorl    %r14d, %r14d    /* nospec   r14*/
         pushq   %r15            /* pt_regs->r15 */
-        xorq    %r15, %r15      /* nospec   r15*/
+        xorl    %r15d, %r15d    /* nospec   r15*/
         UNWIND_HINT_REGS
+        .if \save_ret
+        pushq   %rsi            /* return address on top of stack */
+        .endif
 .endm
 
 .macro POP_REGS pop_rdi=1 skip_r11rcx=0
@@ -172,12 +181,7 @@ For 32-bit we have the following conventions - kernel is built with
  */
 .macro ENCODE_FRAME_POINTER ptregs_offset=0
 #ifdef CONFIG_FRAME_POINTER
-        .if \ptregs_offset
-                leaq \ptregs_offset(%rsp), %rbp
-        .else
-                mov %rsp, %rbp
-        .endif
-        orq     $0x1, %rbp
+        leaq 1+\ptregs_offset(%rsp), %rbp
 #endif
 .endm