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Date: Fri, 21 Jan 2011 23:17:00 +0100
From: matthieu castet <castet.matthieu@free.fr>
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To: "H. Peter Anvin" <hpa@zytor.com>
CC: Lin Ming <ming.m.lin@intel.com>, Oliver Neukum <oneukum@suse.de>,
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Subject: Re: [REGRESSION] S3 resume on SandyBridge doesn't work with NX protection
 (5bd5a45)
References: <20110119173710.GA1331@suse.de> <20110119230602.6dd34fa3@mat-laptop> <20110120134734.GA7230@suse.de> <1295535954.4d384f524c8f0@imp.free.fr> <20110120155909.GA21782@suse.de> <4D38A697.3040308@free.fr> <4D38A836.5040003@zytor.com>
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H. Peter Anvin a écrit :
> On 01/20/2011 01:18 PM, matthieu castet wrote:
>> PS :
>> x86 trampoline is a mess. There are many (wakeup, smpboot) and differ between 32 and 64 bit.
>> H. Peter Anvin, aren't you rewriting them ?
> 
> Yes, working on it, starting with the framework used to install them.
> 
> They can't all be unified; they are used for different purposes and have
> different requirements (for one thing, 32 vs 64 bits require different
> trampoline code), but the install framework patchset is almost done, and
> the recent change of keeping the 1:1 pagetable set around is also a
> dramatic cleanup.
Of course, but for example on x64, using smp trampoline to exit rm wakecode help
to merge code in one place.

Also the start of 32/64 bits trampoline (rm part) is really similar. The main difference is the verify_cpu
check, but can't it be called latter (when we switch to 64 bits ) ?

In the end we could have something like

wakeup_code:
(common rm 16 bit code)
call trampoline

trampoline:
(common rm 16 bit code)
call startup_32_vector (either startup_32_smp for 32 bits (exit trampoline) or startup_32 for 64 bit).

startup_32: