From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e06smtp13.uk.ibm.com (e06smtp13.uk.ibm.com [195.75.94.109]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 64CDB1A0145 for ; Fri, 27 Mar 2015 04:38:06 +1100 (AEDT) Received: from /spool/local by e06smtp13.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 26 Mar 2015 17:38:03 -0000 Received: from b06cxnps4075.portsmouth.uk.ibm.com (d06relay12.portsmouth.uk.ibm.com [9.149.109.197]) by d06dlp03.portsmouth.uk.ibm.com (Postfix) with ESMTP id 46FA01B08067 for ; Thu, 26 Mar 2015 17:38:22 +0000 (GMT) Received: from d06av10.portsmouth.uk.ibm.com (d06av10.portsmouth.uk.ibm.com [9.149.37.251]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t2QHbtuP10813884 for ; Thu, 26 Mar 2015 17:37:55 GMT Received: from d06av10.portsmouth.uk.ibm.com (localhost [127.0.0.1]) by d06av10.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t2QHbsba032124 for ; Thu, 26 Mar 2015 11:37:55 -0600 From: Laurent Dufour To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Jeff Dike , Richard Weinberger , Guan Xuetao , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, Arnd Bergmann , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, user-mode-linux-devel@lists.sourceforge.net, user-mode-linux-user@lists.sourceforge.net, linux-arch@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH v4 0/2] Tracking user space vDSO remaping Date: Thu, 26 Mar 2015 18:37:51 +0100 Message-Id: In-Reply-To: <20150326141730.GA23060@gmail.com> References: <20150326141730.GA23060@gmail.com> Cc: criu@openvz.org, cov@codeaurora.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , CRIU is recreating the process memory layout by remapping the checkpointee memory area on top of the current process (criu). This includes remapping the vDSO to the place it has at checkpoint time. However some architectures like powerpc are keeping a reference to the vDSO base address to build the signal return stack frame by calling the vDSO sigreturn service. So once the vDSO has been moved, this reference is no more valid and the signal frame built later are not usable. This patch serie is introducing a new mm hook 'arch_remap' which is called when mremap is done and the mm lock still hold. The next patch is adding the vDSO remap and unmap tracking to the powerpc architecture. Changes in v4: -------------- - Reviewing the PowerPC part of the patch to handle partial unmap and remap of the vDSO. Changes in v3: -------------- - Fixed grammatical error in a comment of the second patch. Thanks again, Ingo. Changes in v2: -------------- - Following the Ingo Molnar's advice, enabling the call to arch_remap through the __HAVE_ARCH_REMAP macro. This reduces considerably the first patch. Laurent Dufour (2): mm: Introducing arch_remap hook powerpc/mm: Tracking vDSO remap arch/powerpc/include/asm/mmu_context.h | 32 +++++++++++++++++++++++++++- arch/powerpc/kernel/vdso.c | 39 ++++++++++++++++++++++++++++++++++ mm/mremap.c | 11 ++++++++-- 3 files changed, 79 insertions(+), 3 deletions(-) -- 1.9.1