[PATCH v2] x86: Load __USER_DS into DS/ES after resume

[Ingo Molnar <mingo@kernel.org>]

* Linus Torvalds <torvalds@linux-foundation.org> wrote:

> On Jun 13, 2015 8:56 PM, "Ingo Molnar" <mingo@kernel.org> wrote:
> >
> > Ok, so something like the patch below, right?
> >
> >         movw    $__KERNEL_DS, %ax
> >         movw    %ax, %ss
> > -       movw    %ax, %ds
> > -       movw    %ax, %es
> >         movw    %ax, %fs
> >         movw    %ax, %gs
> >
> > +       movw    $__KERNEL_DS, %ax
> > +       movw    %ax, %ds
> > +       movw    %ax, %es
> 
> .. except with less cut-and-paste bugs.
> 
> That second KERNEL should be USER.

Yeah, doh :-/ Updated patch below.

Thanks,

	Ingo

=====
 arch/x86/kernel/acpi/wakeup_32.S | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/acpi/wakeup_32.S b/arch/x86/kernel/acpi/wakeup_32.S
index 665c6b7d2ea9..0c26b1b44e51 100644
--- a/arch/x86/kernel/acpi/wakeup_32.S
+++ b/arch/x86/kernel/acpi/wakeup_32.S
@@ -12,11 +12,13 @@ ENTRY(wakeup_pmode_return)
 wakeup_pmode_return:
 	movw	$__KERNEL_DS, %ax
 	movw	%ax, %ss
-	movw	%ax, %ds
-	movw	%ax, %es
 	movw	%ax, %fs
 	movw	%ax, %gs
 
+	movw	$__USER_DS, %ax
+	movw	%ax, %ds
+	movw	%ax, %es
+
 	# reload the gdt, as we need the full 32 bit address
 	lidt	saved_idt
 	lldt	saved_ldt