mm/sparsemem: get address to page struct instead of address to pfn
authorWei Yang <richardw.yang@linux.intel.com>
Thu, 2 Apr 2020 04:09:24 +0000 (21:09 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 2 Apr 2020 16:35:30 +0000 (09:35 -0700)
commit4627d76dcf0482c56e925a3477948df136255f0c
tree68629f4d3d557cb9743e0761a0cd8eb13fa235f8
parent0c28759ee3c91fa8ae14d7672b781b979be274e1
mm/sparsemem: get address to page struct instead of address to pfn

memmap should be the address to page struct instead of address to pfn.

As mentioned by David, if system memory and devmem sit within a section,
the mismatch address would lead kdump to dump unexpected memory.

Since sub-section only works for SPARSEMEM_VMEMMAP, pfn_to_page() is valid
to get the page struct address at this point.

Fixes: ba72b4c8cf60 ("mm/sparsemem: support sub-section hotplug")
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Baoquan He <bhe@redhat.com>
Link: http://lkml.kernel.org/r/20200210005048.10437-1-richardw.yang@linux.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/sparse.c