Thanks Hari -- the patch is queued for crash-7.2.0:
  
https://github.com/crash-utility/crash/commit/d7b43c2a527503415dd66dff20d...
  
Dave
----- Original Message -----
 Kernel commit 2f18d533757da3899f4bedab0b2c051b080079dc lowered the
 max real address to 53 bits. Max the necessary changes here. Without
 this patch, vmalloc address translation would fail.
 
 Signed-off-by: Hari Bathini <hbathini(a)linux.vnet.ibm.com>
 ---
  defs.h |    5 +++--
  1 file changed, 3 insertions(+), 2 deletions(-)
 
 diff --git a/defs.h b/defs.h
 index c779839..fd97ffe 100644
 --- a/defs.h
 +++ b/defs.h
 @@ -3914,8 +3914,9 @@ struct efi_memory_desc_t {
  #define PMD_MASKED_BITS_64K_4_6  0xc0000000000000ffUL
  
  #define PTE_RPN_MASK_DEFAULT  0xffffffffffffffffUL
 -#define PTE_RPN_SIZE_L4_4_6   (PAGESIZE() == PPC64_64K_PAGE_SIZE ? 41 : 45)
 -#define PTE_RPN_MASK_L4_4_6   (((1UL << PTE_RPN_SIZE_L4_4_6) - 1) <<
 PAGESHIFT())
 +#define PAGE_PA_MAX_L4_4_6    (THIS_KERNEL_VERSION >= LINUX(4,11,0) ? 53 :
 57)
 +#define PTE_RPN_MASK_L4_4_6   \
 +	(((1UL << PAGE_PA_MAX_L4_4_6) - 1) & ~((1UL << PAGESHIFT()) - 1))
  #define PTE_RPN_SHIFT_L4_4_6  PAGESHIFT()
  
  #define PGD_MASKED_BITS_4_7  0xc0000000000000ffUL