From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753239AbdJFI4o (ORCPT ); Fri, 6 Oct 2017 04:56:44 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:49914 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753223AbdJFI4m (ORCPT ); Fri, 6 Oct 2017 04:56:42 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Gerald Schaefer , Martin Schwidefsky Subject: [PATCH 4.9 104/104] s390/mm: make pmdp_invalidate() do invalidation only Date: Fri, 6 Oct 2017 10:52:22 +0200 Message-Id: <20171006083856.197171021@linuxfoundation.org> X-Mailer: git-send-email 2.14.2 In-Reply-To: <20171006083840.743659740@linuxfoundation.org> References: <20171006083840.743659740@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gerald Schaefer commit 91c575b335766effa6103eba42a82aea560c365f upstream. Commit 227be799c39a ("s390/mm: uninline pmdp_xxx functions from pgtable.h") inadvertently changed the behavior of pmdp_invalidate(), so that it now clears the pmd instead of just marking it as invalid. Fix this by restoring the original behavior. A possible impact of the misbehaving pmdp_invalidate() would be the MADV_DONTNEED races (see commits ced10803 and 58ceeb6b), although we should not have any negative impact on the related dirty/young flags, since those flags are not set by the hardware on s390. Fixes: 227be799c39a ("s390/mm: uninline pmdp_xxx functions from pgtable.h") Signed-off-by: Gerald Schaefer Signed-off-by: Martin Schwidefsky Signed-off-by: Greg Kroah-Hartman --- arch/s390/include/asm/pgtable.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -1359,7 +1359,9 @@ static inline pmd_t pmdp_huge_clear_flus static inline void pmdp_invalidate(struct vm_area_struct *vma, unsigned long addr, pmd_t *pmdp) { - pmdp_xchg_direct(vma->vm_mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_INVALID)); + pmd_t pmd = __pmd(pmd_val(*pmdp) | _SEGMENT_ENTRY_INVALID); + + pmdp_xchg_direct(vma->vm_mm, addr, pmdp, pmd); } #define __HAVE_ARCH_PMDP_SET_WRPROTECT