Hi,

On Wed, Jul 14, 2021 at 03:37:36PM +0300, Mike Rapoport wrote:

From: Mike Rapoport <redacted>

Currently memory map for the holes is initialized only when SPARSEMEM
memory model is used. Yet, even with FLATMEM there could be holes in the
physical memory layout that have memory map entries.

For instance, the memory reserved using e820 API on i386 or
"reserved-memory" nodes in device tree would not appear in memblock.memory
and hence the struct pages for such holes will be skipped during memory map
initialization.

These struct pages will be zeroed because the memory map for FLATMEM
systems is allocated with memblock_alloc_node() that clears the allocated
memory. While zeroed struct pages do not cause immediate problems, the
correct behaviour is to initialize every page using __init_single_page().
Besides, enabling page poison for FLATMEM case will trigger
PF_POISONED_CHECK() unless the memory map is properly initialized.

Make sure init_unavailable_range() is called for both SPARSEMEM and FLATMEM
so that struct pages representing memory holes would appear as PG_Reserved
with any memory layout.

Signed-off-by: Mike Rapoport <redacted>

This patch causes microblaze petalogix-ml605 qemu emulations to fail
silently (no console output). Reverting it fixes the problem.

Guenter

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