Re: [PATCHv3 3/4] x86/64/kexec: Map original relocate_kernel() in init_transition_pgtable()

[kirill.shutemov@xxxxxxxxxxxxxxx]

On Tue, Aug 20, 2024 at 11:06:34AM +0000, Huang, Kai wrote:
> At later time:
> 
>         call    swap_pages                                                   
>         movq    $virtual_mapped, %rax  	<---- (1)                            
>         pushq   %rax
>         ANNOTATE_UNRET_SAFE
>         ret  				<---- (2)
> 
> (1) will load the VA which has __START_KERNEL_map to %rax, and after (2) the
> kernel will run at VA of the original relocate_kernel() which maps to the PA
> of the original relcoate_kernel().  But I think the memory page of the
> original relocate_kernel() won't get corrupted after returning from the second
> kernel, so should be safe to use?

Yes.

-- 
  Kiryl Shutsemau / Kirill A. Shutemov