From c2bc5b15eb86a6e8b859e809eb779a24e395a474 Mon Sep 17 00:00:00 2001
From: Dmitry Chagin <dchagin@FreeBSD.org>
Date: Mon, 8 Jun 2015 17:39:25 +0000
Subject: [PATCH] Futex is an aligned 32-bit integer. Use the proper
 instruction and operand when dereferencing futex pointer.

---
 sys/amd64/linux/linux_support.s | 48 ++++++++++++++++-----------------
 1 file changed, 24 insertions(+), 24 deletions(-)

diff --git a/sys/amd64/linux/linux_support.s b/sys/amd64/linux/linux_support.s
index f809d1199b03..2a3ba1a47f11 100644
--- a/sys/amd64/linux/linux_support.s
+++ b/sys/amd64/linux/linux_support.s
@@ -45,9 +45,9 @@ ENTRY(futex_xchgl)
 	movq	$VM_MAXUSER_ADDRESS-4,%rax
 	cmpq	%rax,%rsi
 	ja	futex_fault
-	xchgq	%rdi,(%rsi)
-	movq	%rdi,(%rdx)
-	xorq	%rax,%rax
+	xchgl	%edi,(%rsi)
+	movl	%edi,(%rdx)
+	xorl	%eax,%eax
 	movq	%rax,PCB_ONFAULT(%r8)
 	ret
 
@@ -60,9 +60,9 @@ ENTRY(futex_addl)
 #ifdef SMP
 	lock
 #endif
-	xaddq	%rdi,(%rsi)
-	movq	%rdi,(%rdx)
-	xorq	%rax,%rax
+	xaddl	%edi,(%rsi)
+	movl	%edi,(%rdx)
+	xorl	%eax,%eax
 	movq	%rax,PCB_ONFAULT(%r8)
 	ret
 
@@ -72,16 +72,16 @@ ENTRY(futex_orl)
 	movq	$VM_MAXUSER_ADDRESS-4,%rax
 	cmpq	%rax,%rsi
 	ja	futex_fault
-	movq	(%rsi),%rax
-1:	movq	%rax,%rcx
-	orq	%rdi,%rcx
+	movl	(%rsi),%eax
+1:	movl	%eax,%ecx
+	orl	%edi,%ecx
 #ifdef SMP
 	lock
 #endif
-	cmpxchgq %rcx,(%rsi)
+	cmpxchgl %ecx,(%rsi)
 	jnz	1b
-	movq	%rax,(%rdx)
-	xorq	%rax,%rax
+	movl	%eax,(%rdx)
+	xorl	%eax,%eax
 	movq	%rax,PCB_ONFAULT(%r8)
 	ret
 
@@ -91,16 +91,16 @@ ENTRY(futex_andl)
 	movq	$VM_MAXUSER_ADDRESS-4,%rax
 	cmpq	%rax,%rsi
 	ja	futex_fault
-	movq	(%rsi),%rax
-1:	movq	%rax,%rcx
-	andq	%rdi,%rcx
+	movl	(%rsi),%eax
+1:	movl	%eax,%ecx
+	andl	%edi,%ecx
 #ifdef SMP
 	lock
 #endif
-	cmpxchgq %rcx,(%rsi)
+	cmpxchgl %ecx,(%rsi)
 	jnz	1b
-	movq	%rax,(%rdx)
-	xorq	%rax,%rax
+	movl	%eax,(%rdx)
+	xorl	%eax,%eax
 	movq	%rax,PCB_ONFAULT(%r8)
 	ret
 
@@ -110,15 +110,15 @@ ENTRY(futex_xorl)
 	movq	$VM_MAXUSER_ADDRESS-4,%rax
 	cmpq	%rax,%rsi
 	ja	futex_fault
-	movq	(%rsi),%rax
-1:	movq	%rax,%rcx
-	xorq	%rdi,%rcx
+	movl	(%rsi),%eax
+1:	movl	%eax,%ecx
+	xorl	%edi,%ecx
 #ifdef SMP
 	lock
 #endif
-	cmpxchgq %rcx,(%rsi)
+	cmpxchgl %ecx,(%rsi)
 	jnz	1b
-	movq	%rax,(%rdx)
-	xorq	%rax,%rax
+	movl	%eax,(%rdx)
+	xorl	%eax,%eax
 	movq	%rax,PCB_ONFAULT(%r8)
 	ret