From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756065AbcDGMus (ORCPT ); Thu, 7 Apr 2016 08:50:48 -0400 Received: from mail-am1on0109.outbound.protection.outlook.com ([157.56.112.109]:16330 "EHLO emea01-am1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753176AbcDGMuq (ORCPT ); Thu, 7 Apr 2016 08:50:46 -0400 X-Greylist: delayed 886 seconds by postgrey-1.27 at vger.kernel.org; Thu, 07 Apr 2016 08:50:45 EDT Authentication-Results: virtuozzo.com; dkim=none (message not signed) header.d=none;virtuozzo.com; dmarc=none action=none header.from=virtuozzo.com; Subject: Re: [PATCH 1/2] x86/arch_prctl: add ARCH_SET_{COMPAT,NATIVE} to change compatible mode To: Cyrill Gorcunov , Andy Lutomirski References: <1459960170-4454-1-git-send-email-dsafonov@virtuozzo.com> <1459960170-4454-2-git-send-email-dsafonov@virtuozzo.com> <57064E6C.2030202@virtuozzo.com> <20160407122156.GG2258@uranus.lan> CC: Shuah Khan , "H. 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Do you mean by vdso remapping >> mremap for vdso/vvar pages? I think, it should work now. >> I did remapping for vdso as blob for native x86_64 task differs >> to compatible task. So it's just changing blobs, address value >> is there for convenience - I may omit it and just remap >> different vdso blob at the same place where was previous vdso. >> I'm not sure, why do we need possibility to map 64-bit vdso blob >> on native 32-bit builds? > First of all, thanks a huge for all your comments, Andy! > Dima, I'm not seeing in patch, don't you have to take > mm::mmap_sem when walking over VMAs? I was sure I did, but have missed it, well. Thanks! > > Cyrill -- Regards, Dmitry Safonov