From 60cb98a1bd2e4ea8fda532261f7211f5d4eba9c0 Mon Sep 17 00:00:00 2001
From: Mark Johnston <markj@FreeBSD.org>
Date: Sun, 16 May 2021 22:17:53 -0400
Subject: [PATCH] linux: Fix a mistake in commit fb58045145

The change to futex_andl_smap() should have ordered stac before the
load from a user address, otherwise it does not fix anything.

Fixes:	fb58045145 ("linux: Fix SMAP-enabled futex routines")
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
---
 sys/amd64/linux32/linux32_support.s | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sys/amd64/linux32/linux32_support.s b/sys/amd64/linux32/linux32_support.s
index f3ec3bd8c77..da076010c13 100644
--- a/sys/amd64/linux32/linux32_support.s
+++ b/sys/amd64/linux32/linux32_support.s
@@ -168,8 +168,8 @@ ENTRY(futex_andl_smap)
 	movq	$VM_MAXUSER_ADDRESS-4,%rax
 	cmpq	%rax,%rsi
 	ja	futex_fault
-	movl	(%rsi),%eax
 	stac
+	movl	(%rsi),%eax
 1:	movl	%eax,%ecx
 	andl	%edi,%ecx
 #ifdef SMP