Change in coreboot[master]: arch/x86: Save resume vector to stack in x86_64 mode

[Arthur Heymans (Code Review)]

Attention is currently required from: Iru Cai, Iru Cai (vimacs).
Arthur Heymans has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/55947 )

Change subject: arch/x86: Save resume vector to stack in x86_64 mode
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Patch Set 2: Code-Review+1

(2 comments)

File src/arch/x86/wakeup.S:

https://review.coreboot.org/c/coreboot/+/55947/comment/424e3766_96d6a429 
PS2, Line 20: It's OK to overwrite the return address at (%rsp) because this
            : 	 * function doesn't return.
Is that happening? This looks like a 32bit op so I would expect the upper 4 bytes of 4(%rsp) to be preserved?

https://review.coreboot.org/c/coreboot/+/55947/comment/5a7ea5a7_a4f44043 
PS2, Line 23: mov
Explicitly use movl to make sure only 4 bytes get moved?