linux/arch/sparc/mm
Mike Rapoport ee7c795313 sparc32: register memory occupied by kernel as memblock.memory
sparc32 never registered the memory occupied by the kernel image with
memblock_add() and it only reserved this memory with meblock_reserve().

With openbios as system firmware, the memory occupied by the kernel is
reserved in openbios and removed from mem.available. The prom setup code in
the kernel uses mem.available to set up the memory banks and essentially
there is a hole for the memory occupied by the kernel image.

Later in bootmem_init() this memory is memblock_reserve()d.

Up until recently, memmap initialization would call __init_single_page()
for the pages in that hole, the free_low_memory_core_early() would mark
them as reserved and everything would be Ok.

After the change in memmap initialization introduced by the commit "mm:
memmap_init: iterate over memblock regions rather that check each PFN", the
hole is skipped and the page structs for it are not initialized. And when
they are passed from memblock to page allocator as reserved, the latter
gets confused.

Simply registering the memory occupied by the kernel with memblock_add()
resolves this issue.

Tested on qemu-system-sparc with Debian Etch [1] userspace.

[1] https://people.debian.org/~aurel32/qemu/sparc/debian_etch_sparc_small.qcow2

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Link: https://lkml.kernel.org/r/20200517000050.GA87467@roeck-us.nlllllet/
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-02 18:44:55 -07:00
..
extable.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fault_32.c mm: allow VM_FAULT_RETRY for multiple times 2020-04-02 09:35:30 -07:00
fault_64.c mm: allow VM_FAULT_RETRY for multiple times 2020-04-02 09:35:30 -07:00
highmem.c sparc32: use pgtable-nopud instead of 4level-fixup 2019-12-04 19:44:15 -08:00
hugetlbpage.c sparc64: add support for folded p4d page tables 2020-01-30 11:14:28 +01:00
hypersparc.S sparc32: mm: Restructure sparc32 MMU page-table layout 2020-05-13 15:32:00 -07:00
init_32.c sparc32: register memory occupied by kernel as memblock.memory 2020-06-02 18:44:55 -07:00
init_64.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc 2020-01-30 07:36:43 -08:00
init_64.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
io-unit.c sparc32: use per-device dma_ops 2020-04-02 18:11:55 -07:00
iommu.c sparc32: use per-device dma_ops 2020-04-02 18:11:55 -07:00
leon_mm.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile sparc64: use the generic get_user_pages_fast code 2019-07-12 11:05:44 -07:00
mm_32.h sparc32: use per-device dma_ops 2020-04-02 18:11:55 -07:00
srmmu_access.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
srmmu.c sparc32: mm: Change pgtable_t type to pte_t * instead of struct page * 2020-05-13 15:32:00 -07:00
swift.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
tlb.c mm: fix races between swapoff and flush dcache 2018-04-05 21:36:26 -07:00
tsb.c sparc64: Add support for ADI (Application Data Integrity) 2018-03-18 07:38:48 -07:00
tsunami.S License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ultra.S sparc64: Fix regression in non-hypervisor TLB flush xcall 2019-06-02 22:13:40 -07:00
viking.S sparc32: mm: Restructure sparc32 MMU page-table layout 2020-05-13 15:32:00 -07:00