Re: [PATCH] x86 ACPI: Fix breakage of resume on 64-bit UP systems with SMP kernel

[Pavel Machek <pavel@suse.cz>]

On Fri 2008-10-17 01:26:27, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rjw@sisk.pl>
> 
> x86 ACPI: Fix breakage of resume on 64-bit UP systems with SMP kernel
> 
> We are now using per CPU GDT tables in head_64.S and the original
> early_gdt_descr.address is invalidated after boot by 
> setup_per_cpu_areas().  This breaks resume from suspend to RAM on
> x86_64 UP systems using SMP kernels, because this part of head_64.S
> is also executed during the resume and the invalid GDT address
> causes the system to crash.  It doesn't break on 'true' SMP systems,
> because early_gdt_descr.address is modified every time
> native_cpu_up() runs.  However, during resume it should point to the
> GDT of the boot CPU rather than to another CPU's GDT.
> 
> For this reason, during suspend to RAM always make
> early_gdt_descr.address point to the boot CPU's GDT.
> 
> This fixes http://bugzilla.kernel.org/show_bug.cgi?id=11568, which
> is a regression from 2.6.26.
> 
> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
> Reported-and-tested-by: Andy Wettstein <ajw1980@gmail.com>

Acked-by: Pavel Machek <pavel@suse.cz>
									Pavel

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