hack for getting suspend/resume to half work on an IBM Thinkpad x60s [SMP]

[Andrea Bittau]

On Tue, Oct 03, 2006 at 02:03:31PM -0700, Nate Lawson wrote:
> I agree.  The standard switch to protected mode, paging, etc. needs to 
> be performed and then resume from the saved register context.

I guess my point was that there are two pieces of code that do that:
1) mpboot.s bootMP() used by system bootstrap and what my current patch uses.  I
   think this is what you guys are suggesting to use, and I'm doing it anyway in
   my patch, but I just want to be the devil's advocate =D.

2) acpi_wakecode.S wakeup_16() used by the BSP to wake itself up.  This is what
   I was suggesting should be generalized and used by the other cores too.  The
   difference of this code as opposed to #1 is that #2 can "cheat".  That is, we
   can create the code for #2 on the fly and do stuff like mov old_eax,eax etc
   and don't have to be smart about figuring out where the CPU should land and
   how it should initialize itself [as in the case of #1].

I'm just wondering whether we should do something about the assembly "code
duplication" in #1 and #2.  I understand they serve a different purpose, but
arguably, they do the same thing: real-mode -> jump in kernel.  What is
different is what happens once in kernel mode: boot or resume?  That difference
could be coded in the C part of the kernel leaving a single asm entry point both
for bootstrap and wakeup code.  Am I making any sense? =D