Messages in this thread | ![/](/images/icornerl.gif) | | Date | Wed, 13 Jan 2021 13:23:22 +0200 | From | Mike Rapoport <> | Subject | Re: [PATCH v3 1/2] x86/setup: don't remove E820_TYPE_RAM for pfn 0 |
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On Wed, Jan 13, 2021 at 09:56:49AM +0100, Oscar Salvador wrote: > On Mon, Jan 11, 2021 at 09:40:16PM +0200, Mike Rapoport wrote: > > From: Mike Rapoport <rppt@linux.ibm.com> > > > > The first 4Kb of memory is a BIOS owned area and to avoid its allocation > > for the kernel it was not listed in e820 tables as memory. As the result, > > pfn 0 was never recognised by the generic memory management and it is not a > > part of neither node 0 nor ZONE_DMA. > > So, since it never was added to memblock.memory structs, it was not > initialized by init_unavailable_mem, right?
Actually it was initialized by init_unavailable_mem() and got zone=0 and node=0, but the DMA zone started from pfn 1, so pfn 0 was never a part of ZONE_DMA.
> -- > Oscar Salvador > SUSE L3
-- Sincerely yours, Mike.
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