[PATCH 04/13] x86/crypto/aesni-intel_avx: Standardize stack alignment prologue

From: Josh Poimboeuf
Date: Wed Feb 24 2021 - 11:36:13 EST


Use RBP instead of R14 for saving the old stack pointer before
realignment. This resembles what compilers normally do.

This enables ORC unwinding by allowing objtool to understand the stack
realignment.

Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
---
arch/x86/crypto/aesni-intel_avx-x86_64.S | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/arch/x86/crypto/aesni-intel_avx-x86_64.S b/arch/x86/crypto/aesni-intel_avx-x86_64.S
index 188f1848a730..98e3552b6e03 100644
--- a/arch/x86/crypto/aesni-intel_avx-x86_64.S
+++ b/arch/x86/crypto/aesni-intel_avx-x86_64.S
@@ -251,22 +251,20 @@ VARIABLE_OFFSET = 16*8
.macro FUNC_SAVE
push %r12
push %r13
- push %r14
push %r15

- mov %rsp, %r14
-
-
+ push %rbp
+ mov %rsp, %rbp

sub $VARIABLE_OFFSET, %rsp
and $~63, %rsp # align rsp to 64 bytes
.endm

.macro FUNC_RESTORE
- mov %r14, %rsp
+ mov %rbp, %rsp
+ pop %rbp

pop %r15
- pop %r14
pop %r13
pop %r12
.endm
--
2.29.2