On Wed, 2019-07-24 at 08:46:34 UTC, Nicholas Piggin wrote:
> 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>
> Reviewed-by: Aneesh Kumar K.V <aneesh.ku...@linux.ibm.com>
Series applied to powerpc next, thanks.
https://git.kernel.org/powerpc/c/8f51e3929470942e6a8744061254fdeef646cd36
cheers
