create_physical_mapping expects physical addresses, but creating and
splitting these mappings after boot is supplying virtual (effective)
addresses. This can be irritated by booting with mem= to limit memory
then probing an unused physical memory range:

  echo <addr> > /sys/devices/system/memory/probe

This mostly works by accident, firstly because __va(__va(x)) == __va(x)
so the virtual address does not get corrupted. Secondly because pfn_pte
masks out the upper bits of the pfn beyond the physical address limit,
so a pfn constructed with a 0xc000000000000000 virtual linear address
will be masked back to the correct physical address in the pte.

Cc: Reza Arbab <ar...@linux.vnet.ibm.com>
Fixes: 6cc27341b21a8 ("powerpc/mm: add radix__create_section_mapping()")
Signed-off-by: Nicholas Piggin <npig...@gmail.com>
---
 arch/powerpc/mm/book3s64/radix_pgtable.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c 
b/arch/powerpc/mm/book3s64/radix_pgtable.c
index b4ca9e95e678..c5cc16ab1954 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -902,7 +902,7 @@ int __meminit radix__create_section_mapping(unsigned long 
start, unsigned long e
                return -1;
        }
 
-       return create_physical_mapping(start, end, nid);
+       return create_physical_mapping(__pa(start), __pa(end), nid);
 }
 
 int __meminit radix__remove_section_mapping(unsigned long start, unsigned long 
end)
-- 
2.22.0

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