From: John David Anglin <dave.anglin@bell.net>
Date: Tue, 25 Jul 2017 21:23:35 +0000 (-0400)
Subject: parisc: Extend disabled preemption in copy_user_page
X-Git-Tag: archive/raspbian/4.9.51-1+rpi1~7^2~528
X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/%22/%22http:/www.example.com/cgi/%22?a=commitdiff_plain;h=f0d23fa632430cee981ea2b662b52c62915fc9bc;p=linux-4.9.git

parisc: Extend disabled preemption in copy_user_page

commit 56008c04ebc099940021b714da2d7779117cf6a7 upstream.

It's always bothered me that we only disable preemption in
copy_user_page around the call to flush_dcache_page_asm.
This patch extends this to after the copy.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/arch/parisc/kernel/cache.c b/arch/parisc/kernel/cache.c
index 139803a5d8cd..c721ea2fdbd8 100644
--- a/arch/parisc/kernel/cache.c
+++ b/arch/parisc/kernel/cache.c
@@ -452,8 +452,8 @@ void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
 	  before it can be accessed through the kernel mapping. */
 	preempt_disable();
 	flush_dcache_page_asm(__pa(vfrom), vaddr);
-	preempt_enable();
 	copy_page_asm(vto, vfrom);
+	preempt_enable();
 }
 EXPORT_SYMBOL(copy_user_page);