Re: [PATCH] Fix reloading GDT on ACPI S3 wakeup (fwd)

Re: [PATCH] Fix reloading GDT on ACPI S3 wakeup (fwd)

[Pavel Machek]

Hi!

> This patch - based on
> http://marc.theaimsgroup.com/?l=linux-kernel&m=110055503031009&w=2 -
> makes ACPI S3 wakeup work for me on a ThinkPad T40p laptop with a SMP
> kernel. Without it only UP kernels work. I've been using the patch for
> three months now without any issues.
> 
> The ACPI resume code currently uses a real-mode 16-bit lgdt instruction
> to reload the GDT.  This only restores the lower 24 bits of the GDT base
> address.  In recent SMP kernels, the GDT seems to have moved out of the
> lower 16 megs, thereby causing the ACPI resume to fail -- an invalid GDT
> was being loaded.
> 

Actually x86-64 needs this, too. Any testers?
									Pavel

--- clean/arch/x86_64/kernel/acpi/wakeup.S	2005-01-22 21:24:51.000000000 +0100
+++ linux/arch/x86_64/kernel/acpi/wakeup.S	2005-04-14 22:34:18.000000000 +0200
@@ -67,7 +67,7 @@
 	shll	$4, %eax
 	addl	$(gdta - wakeup_code), %eax
 	movl	%eax, gdt_48a +2 - wakeup_code
-	lgdt	%ds:gdt_48a - wakeup_code		# load gdt with whatever is
+	lgdtl	%ds:gdt_48a - wakeup_code	# load gdt with whatever is
 						# appropriate
 
 	movl	$1, %eax			# protected mode (PE) bit


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