[PATCH RFC v1 3/3] ARM hibernation / suspend-to-disk
sebastian.capella at linaro.org
Fri Feb 21 18:59:11 EST 2014
- Cyril Chemparathy as his email is bouncing back to me.
Quoting Sebastian Capella (2014-02-21 10:39:56)
> Quoting Lorenzo Pieralisi (2014-02-20 08:27:55)
> > > > > + cpu_switch_mm(idmap_pgd, &init_mm);
[ ... ]
> I can try removing it and seeing if there are side effects.
FYI, It's definitely hanging with this removed, still looking.
> In this state I believe:
> - our stack is safe because it's in nosave.
> - userspace is frozen, those pages are 'don't care', as we're
> discarding its state.
> - our instructions and globals are ok, because they're in the
> same place as last boot and are not getting restored. None are in
> - Globals: restore_pblist, idmap_pgd, init_mm, swapper_pg_dir
Sorry, this last bit about the globals is not correct. Of course
they're getting restored. What I meant to say is that they shouldn't
be affected by the mmu switch as they remain at the same address.
For our purposes, I think we won't care about their state as we're not
referencing them after we start restoring. We start the list
with restore_pblist, but after following the initial pointer, we don't
reference it again. From then on, we're walking safe memory lists.
Sorry for the misleading statements.
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