On Mon, Mar 29, 2021 at 10:28:47AM -0400, Pavel Tatashin wrote:
commit ee7febce051945be28ad86d16a15886f878204de upstream.
Memory hotplug may fail on systems with CONFIG_RANDOMIZE_BASE because the
linear map range is not checked correctly.
The start physical address that linear map covers can be actually at the
end of the range because of randomization. Check that and if so reduce it
to 0.
This can be verified on QEMU with setting kaslr-seed to ~0ul:
memstart_offset_seed = 0xffff
START: __pa(_PAGE_OFFSET(vabits_actual)) = ffff9000c0000000
END: __pa(PAGE_END - 1) = 1000bfffffff
Fixes: 58284a901b42 ("arm64/mm: Validate hotplug range before creating linear mapping")
Signed-off-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
Tested-by: Tyler Hicks <tyhicks@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Queued up, thanks!
--
Thanks,
Sasha
