From 0f6f281b731d20bfe75c13f85d33f3f05b440222 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Thu, 26 Jul 2012 08:53:06 +0200 Subject: s390/mm: downgrade page table after fork of a 31 bit process The downgrade of the 4 level page table created by init_new_context is currently done only in start_thread31. If a 31 bit process forks the new mm uses a 4 level page table, including the task size of 2<<42 that goes along with it. This is incorrect as now a 31 bit process can map memory beyond 2GB. Define arch_dup_mmap to do the downgrade after fork. Cc: stable@vger.kernel.org Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/processor.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/s390/include/asm/processor.h') diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h index c40fa91e38a..11e4e323693 100644 --- a/arch/s390/include/asm/processor.h +++ b/arch/s390/include/asm/processor.h @@ -120,7 +120,9 @@ struct stack_frame { regs->psw.mask = psw_user_bits | PSW_MASK_BA; \ regs->psw.addr = new_psw | PSW_ADDR_AMODE; \ regs->gprs[15] = new_stackp; \ + __tlb_flush_mm(current->mm); \ crst_table_downgrade(current->mm, 1UL << 31); \ + update_mm(current->mm, current); \ } while (0) /* Forward declaration, a strange C thing */ -- cgit v1.2.3-70-g09d2