[Crash-utility] [PATCHv7 1/4] crash-utility/arm64: introduce a dedicated field to record the mem layout changes

[Pingfan Liu]

On Tue, Jun 8, 2021 at 3:52 PM HAGIO KAZUHITO(萩尾　一仁) <k-hagio-ab at nec.com> wrote:
>
> -----Original Message-----
> >
> > At present, we have the following important changes for arm64 memory
> > layout:
> >
> > -1. redesigned ARM64 kernel virtual memory layout and associated KASLR
> >     support that was introduced in Linux 4.6. And NEW_VMEMMAP is used to
> >     flag it.
> > -2. memory layout flipped just right before introducing 52-bits kernel.
> > -3. introducing of vabits_actual and phyvirt_offset in kernel
> > -4. removing phyvirt_offset.
> >
> > These changes have effects on PTOV()/VTOP() formula. So introducing a
> > dedicate field mmlayout_flags to record it.
>
> arm64 already has machine_specific.flags, can't we use this?
>
Yes, flags should have enough capacity for now. Adopt it.

> Also, to record the type of memory layout is good, please display it with
> "help -m".
>
OK, I will do it.

> And I'd prefer shorter names like HAS_PHYSVIRT_OFFSET and FLIPPED_VM for
> them, as they will be shown in "help -m".
>
Adopt.

Thanks,

Pingfan