Re: [PATCH] x86, mm: Reserver some memory for bootmem allocator for NO_BOOTMEM

From: Feng Tang
Date: Fri Aug 31 2018 - 02:13:32 EST

On Thu, Aug 30, 2018 at 03:25:42PM +0200, Thomas Gleixner wrote:

> And where is the problem? We know that we need the fixmap during early boot
> anyway, so allocating the PTE page statically and setting it up early
> enough is not really rocket science. No allocator required.

Further check shows the page table for fixmap is already setup in [-12M, -10M],
but fixmap's address space breaks the expection under certain kernel config.
So here is another fix, please review, thanks!