From 61e18270f604c744ed9f8f1b740022516f9726f8 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Thu, 1 Mar 2018 14:40:52 -0800 Subject: [PATCH] s390: Fix runtime warning about negative pgtables_bytes 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 b4e98d9ac775 ("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 Cc: Heiko Carstens Fixes: b4e98d9ac775 ("mm: account pud page tables") Signed-off-by: Guenter Roeck Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/mmu_context.h | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/s390/include/asm/mmu_context.h b/arch/s390/include/asm/mmu_context.h index 65154eaa3714..6c8ce15cde7b 100644 --- a/arch/s390/include/asm/mmu_context.h +++ b/arch/s390/include/asm/mmu_context.h @@ -63,6 +63,7 @@ static inline int init_new_context(struct task_struct *tsk, _ASCE_USER_BITS | _ASCE_TYPE_SEGMENT; /* pgd_alloc() did not account this pmd */ mm_inc_nr_pmds(mm); + mm_inc_nr_puds(mm); } crst_table_init((unsigned long *) mm->pgd, pgd_entry_type(mm)); return 0;