Re: ARM: static kernel in vmalloc space

[Arnd Bergmann]

On Sat, May 16, 2020 at 8:06 AM afzal mohammed <afzal.mohd.ma@xxxxxxxxx> wrote:
>
> On Thu, May 14, 2020 at 05:32:41PM +0200, Arnd Bergmann wrote:
>
> > Typical distros currently offer two kernels, with and without LPAE,
> > and they probably don't want to add a third one for LPAE with
> > either highmem or vmsplit-4g-4g. Having extra user address
> > space and more lowmem is both going to help users that
> > still have 8GB configurations.
>
> Okay, so the conclusion i take is,
>
> 1. VMSPLIT 4G/4G have to live alongside highmem
> 2. For user space copy, do pinning followed by kmap

Right, though kmap_atomic() should be sufficient here
because it is always a short-lived mapping.

      Arnd