linux-kernel - [PATCH] x86, asm: Use CC_SET()/CC_OUT() for __cmpxchg

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date:   Mon, 20 Aug 2018 17:22:16 +0200
From:   Uros Bizjak <ubizjak@...il.com>
To:     linux-kernel@...r.kernel.org
Cc:     x86@...nel.org, Uros Bizjak <ubizjak@...il.com>
Subject: [PATCH] x86, asm: Use CC_SET()/CC_OUT() for __cmpxchg_double

Remove open-coded uses of set instructions to use CC_SET()/CC_OUT() for __cmpxchg_double.

Signed-off-by: Uros Bizjak <ubizjak@...il.com>
---
 arch/x86/include/asm/cmpxchg.h | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/cmpxchg.h b/arch/x86/include/asm/cmpxchg.h
index a55d79b233d3..bfb85e5844ab 100644
--- a/arch/x86/include/asm/cmpxchg.h
+++ b/arch/x86/include/asm/cmpxchg.h
@@ -242,10 +242,12 @@ extern void __add_wrong_size(void)
 	BUILD_BUG_ON(sizeof(*(p2)) != sizeof(long));			\
 	VM_BUG_ON((unsigned long)(p1) % (2 * sizeof(long)));		\
 	VM_BUG_ON((unsigned long)((p1) + 1) != (unsigned long)(p2));	\
-	asm volatile(pfx "cmpxchg%c4b %2; sete %0"			\
-		     : "=a" (__ret), "+d" (__old2),			\
-		       "+m" (*(p1)), "+m" (*(p2))			\
-		     : "i" (2 * sizeof(long)), "a" (__old1),		\
+	asm volatile(pfx "cmpxchg%c5b %1"				\
+		     CC_SET(e)						\
+		     : CC_OUT(e) (__ret),				\
+		       "+m" (*(p1)), "+m" (*(p2)),			\
+		       "+a" (__old1), "+d" (__old2)			\
+		     : "i" (2 * sizeof(long)),				\
 		       "b" (__new1), "c" (__new2));			\
 	__ret;								\
 })
-- 
2.17.1