When running s390 images with 'compat' processes, the following
BUG is seen repeatedly.
BUG: non-zero pgtables_bytes on freeing mm: -16384
Bisect points to commit b4e98d9ac7 ("mm: account pud page tables").
Analysis shows that init_new_context() is called with
mm->context.asce_limit set to _REGION3_SIZE. In this situation,
pgtables_bytes remains set to 0 and is not increased. The message is
displayed when the affected process dies and mm_dec_nr_puds() is called.
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Fixes: b4e98d9ac7 ("mm: account pud page tables")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
61e18270f6