From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BFC19C2BA2B for ; Wed, 8 Apr 2020 09:48:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 972962074F for ; Wed, 8 Apr 2020 09:48:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="AtfViQT1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727180AbgDHJsu (ORCPT ); Wed, 8 Apr 2020 05:48:50 -0400 Received: from mail-lj1-f194.google.com ([209.85.208.194]:39428 "EHLO mail-lj1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726792AbgDHJsu (ORCPT ); Wed, 8 Apr 2020 05:48:50 -0400 Received: by mail-lj1-f194.google.com with SMTP id i20so6915019ljn.6 for ; Wed, 08 Apr 2020 02:48:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=eEezST1RXJ88ybnVOwFKxlJ6+MPqHS1LvuVkjRbNDs4=; b=AtfViQT1klZEFep9wTrnlBNvl75uK2hyUO/WqUNRXSA41ipnxHC6/JdTZ3LZ2pYsiD aVWUeYmPUfXymIYFRcLAfKqAtXhxI+0x8F71hJj3VwT8OA2db3sAhZcSKfJdwPs33Jdm ebi6utBvs/stkR0zNal8RJLdCUJdcqw56v97JaMJ4h1bgaiSQAzOSbUGbLJ+c5tQnb2f gp6kz/XUdx2fc8Nq4gRN9GAzGAtdlLOEChwhCUBlQ5q6OMPNHqw2tKWqI2YcCq8exhku 4UumWQGM+wUD+m2N6hhQYDG5WC9E5o0NH2k0LGeMMn6+O0BGBEeEQugb4L+3crwWu09L a/dg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=eEezST1RXJ88ybnVOwFKxlJ6+MPqHS1LvuVkjRbNDs4=; b=pdpEmqoRLGxWotf2crWMwvBrDI5Wfv7VAMSE9yWqRBpD7etf0tbe9q4TK6OIFrJgBQ mLGF2qyCP3cMM96v+WIO9Oeu02wyEQGPujks/y23gu9qt7Z6zutCYf8e4P8WLODXTYvn tfGOs/C9z99r2jhYXurBhLZLr7Q/RrG4CbpjmsMoZQCRULs2ne5h03Kxl3OwU7/wQ8Kl KhQPKyOFivAP3D/HCAM11Ful1ylAGZozWs4XPaQ0J0uW3OE8cAj7Z6E7zcPSqwfJjJLO xoJEoybQQeaMAV7JF74l8V4f5IsH12orsrZ2gG0Co+DJng2nPNDNR/l5bGL8i5gfZQqq XvMA== X-Gm-Message-State: AGi0PuYhTtLkQsx16+AYHi8rRF5KRjV8CFE4nznpXyNEci8N4z/Ndl9g 4RrHb/4FhSZhFshgUsUQNwY/PXkKd2W9YBwXNUV/xQ== X-Google-Smtp-Source: APiQypKzRT3tjcthaIy1IYrParD4m/MJGtYTGgck/20gGjrf0nKgcCSDB9gBB+Pbu1aw6GTj8C+5BqYtxFna/wpkfJg= X-Received: by 2002:a2e:5048:: with SMTP id v8mr4074814ljd.99.1586339328475; Wed, 08 Apr 2020 02:48:48 -0700 (PDT) MIME-Version: 1.0 References: <20200318205337.16279-1-sashal@kernel.org> <20200318205337.16279-30-sashal@kernel.org> In-Reply-To: From: Jann Horn Date: Wed, 8 Apr 2020 11:48:22 +0200 Message-ID: Subject: backport request for 3.16 [was: Re: [PATCH AUTOSEL 5.4 30/73] futex: Fix inode life-time issue] To: stable , Ben Hutchings Cc: kernel list , Peter Zijlstra , Linus Torvalds , Sasha Levin , linux-fsdevel , Greg Kroah-Hartman Content-Type: text/plain; charset="UTF-8" Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org @Ben: You'll probably also want to take these two into the next 3.16 release. Sorry, I forgot that 3.16 has a different maintainer... On Mon, Mar 23, 2020 at 8:18 PM Jann Horn wrote: > > On Wed, Mar 18, 2020 at 9:54 PM Sasha Levin wrote: > > > > From: Peter Zijlstra > > > > [ Upstream commit 8019ad13ef7f64be44d4f892af9c840179009254 ] > > > > As reported by Jann, ihold() does not in fact guarantee inode > > persistence. And instead of making it so, replace the usage of inode > > pointers with a per boot, machine wide, unique inode identifier. > > > > This sequence number is global, but shared (file backed) futexes are > > rare enough that this should not become a performance issue. > > Please also take this patch, together with > 8d67743653dce5a0e7aa500fcccb237cde7ad88e "futex: Unbreak futex > hashing", into the older stable branches. This has to go all the way > back; as far as I can tell, the bug already existed at the beginning > of git history.