[PATCH 4.12 06/31] parisc: Extend disabled preemption in copy_user_page

From: Greg Kroah-Hartman
Date: Thu Aug 03 2017 - 19:25:05 EST

4.12-stable review patch. If anyone has any objections, please let me know.


From: John David Anglin <dave.anglin@xxxxxxxx>

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@xxxxxxxx>
Signed-off-by: Helge Deller <deller@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

arch/parisc/kernel/cache.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/parisc/kernel/cache.c
+++ b/arch/parisc/kernel/cache.c
@@ -453,8 +453,8 @@ void copy_user_page(void *vto, void *vfr
before it can be accessed through the kernel mapping. */
flush_dcache_page_asm(__pa(vfrom), vaddr);
- preempt_enable();
copy_page_asm(vto, vfrom);
+ preempt_enable();