From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751503AbaESW6m (ORCPT ); Mon, 19 May 2014 18:58:42 -0400 Received: from mail-pa0-f48.google.com ([209.85.220.48]:53357 "EHLO mail-pa0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751237AbaESW6k (ORCPT ); Mon, 19 May 2014 18:58:40 -0400 From: Andy Lutomirski To: x86@kernel.org, Andrew Morton , Sasha Levin , "linux-mm@kvack.org" , Dave Jones Cc: LKML , Cyrill Gorcunov , Pavel Emelyanov , "H. Peter Anvin" , Andy Lutomirski Subject: [PATCH 0/4] x86,mm: vdso fixes for an OOPS and /proc/PID/maps Date: Mon, 19 May 2014 15:58:30 -0700 Message-Id: X-Mailer: git-send-email 1.9.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [This applies to tip/x86/vdso. Patch 1/4 is a resend.] This fixes an OOPS on systems without an HPET and incomplete information in /proc/PID/maps. The latter is done by adding a new vm_ops callback to replace arch_vma_name, which is inflexible and awkward to use correctly. With this series applied, calling mremap on the vdso results in sensible output in /proc/PID/maps and the vvar area shows up correctly. I don't want to guarantee that mremap on the vdso will do anything sensible right now, but that's unchanged from before. In fact, I suspect that mremapping the vdso on 32-bit tasks is rather broken right now due to sigreturn. In current kernels, mremapping the vdso blows away the name: badc0de0000-badc0de2000 r-xp 00000000 00:00 0 Now it doesn't: badc0de0000-badc0de1000 r-xp 00000000 00:00 0 [vdso] As a followup, it might pay to replace install_special_mapping with a new install_vdso_mapping function that hardcodes the "[vdso]" name, to separately fix all the other arch_vma_name users (maybe just ARM?) and then kill arch_vma_name completely. NB: This touches core mm code. I'd appreciate some review by the mm folks. Andy Lutomirski (4): x86,vdso: Fix an OOPS accessing the hpet mapping w/o an hpet mm,fs: Add vm_ops->name as an alternative to arch_vma_name x86,mm: Improve _install_special_mapping and fix x86 vdso naming x86,mm: Replace arch_vma_name with vm_ops->name for vsyscalls arch/x86/include/asm/vdso.h | 6 ++- arch/x86/mm/init_64.c | 20 +++++----- arch/x86/vdso/vdso2c.h | 5 ++- arch/x86/vdso/vdso32-setup.c | 7 ---- arch/x86/vdso/vma.c | 26 ++++++++----- fs/binfmt_elf.c | 8 ++++ fs/proc/task_mmu.c | 6 +++ include/linux/mm.h | 10 ++++- include/linux/mm_types.h | 6 +++ mm/mmap.c | 89 +++++++++++++++++++++++++++++--------------- 10 files changed, 124 insertions(+), 59 deletions(-) -- 1.9.0