From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Mon, 18 Sep 2017 14:42:05 -0500
Subject: crypto: x86/sha1-avx2 - Fix RBP usage
Git-commit: d7b1722c72aa915283ada27709c6feeb392f6038
Patch-mainline: v4.14-rc2
References: bnc#1058115
Using RBP as a temporary register breaks frame pointer convention and
breaks stack traces when unwinding from an interrupt in the crypto code.
Use R11 instead of RBP. Since R11 isn't a callee-saved register, it
doesn't need to be saved and restored on the stack.
Reported-by: Eric Biggers <ebiggers@google.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Eric Biggers <ebiggers@google.com>
Acked-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
arch/x86/crypto/sha1_avx2_x86_64_asm.S | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
--- a/arch/x86/crypto/sha1_avx2_x86_64_asm.S
+++ b/arch/x86/crypto/sha1_avx2_x86_64_asm.S
@@ -89,7 +89,7 @@
#define REG_RE %rdx
#define REG_RTA %r12
#define REG_RTB %rbx
-#define REG_T1 %ebp
+#define REG_T1 %r11d
#define xmm_mov vmovups
#define avx2_zeroupper vzeroupper
#define RND_F1 1
@@ -637,7 +637,6 @@ _loop3:
ENTRY(\name)
push %rbx
- push %rbp
push %r12
push %r13
push %r14
@@ -673,7 +672,6 @@ _loop3:
pop %r14
pop %r13
pop %r12
- pop %rbp
pop %rbx
ret