Re: [PATCH]: ACPI: preserve the ebx value in acpi_copy_wakeup_routine

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Hi!

> From: Tian Kevin <kevin.tian@xxxxxxxxx>
> 
> Register %ebx serves as the "global offset table base register"
> for position-independent code. For absolute code, %ebx serves
> as a local register and has no specified role in the function
> calling sequence. In either case, a function must preserve the
> register value for the caller.
> 
> acpi_copy_wakeup_routine overrides %ebx without saving it,
> this may corrupt the called data.
> 
> Kevin found that most time the value of Sx is saved in %esi,
> however sometimes compiler also uses %ebx. When this happens,
> suspends fails since sleep value in ebx is changed by
> acpi_copy_wakeup_routine.
> 
> The same funtion in X86_64 doesn't have this problem.
> 
> Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx>

Looks okay to me. That routine also corrupts ecx and edx, hopefully
that's okay?
								Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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