From patchwork Mon Dec 11 14:20:31 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joseph Salisbury X-Patchwork-Id: 847081 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=lists.ubuntu.com (client-ip=91.189.94.19; helo=huckleberry.canonical.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=) Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 3ywQBB4DZ5z9ryk; Tue, 12 Dec 2017 01:21:38 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.86_2) (envelope-from ) id 1eOOxa-0006zI-1z; Mon, 11 Dec 2017 14:21:34 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:128) (Exim 4.86_2) (envelope-from ) id 1eOOxV-0006x9-V8 for kernel-team@lists.ubuntu.com; Mon, 11 Dec 2017 14:21:29 +0000 Received: from 1.general.jsalisbury.us.vpn ([10.172.67.212] helo=salisbury) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1eOOwc-0003HR-UC for kernel-team@lists.ubuntu.com; Mon, 11 Dec 2017 14:20:35 +0000 Received: by salisbury (Postfix, from userid 1000) id E99357E26DB; Mon, 11 Dec 2017 09:20:33 -0500 (EST) From: Joseph Salisbury To: kernel-team@lists.ubuntu.com Subject: [SRU][Zesty][v2][PATCH 0/2] UBUNTU: SAUCE: (no-up) Fixes for LP:1729145 Date: Mon, 11 Dec 2017 09:20:31 -0500 Message-Id: X-Mailer: git-send-email 2.7.4 X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" BugLink: http://bugs.launchpad.net/bugs/1729145 == SRU Justification == This bug is preventing /dev/bcache/by-uuid links from beingcreated after reboot. It appears that since the initramfs loads the bcache module which probes and finds all of the cache devices and backing devices then once the rootfs is mounted and udev gets to run, the bcache kernel module does not emit the CACHED_UUID value into the environment if the underlying devices are already registered. With this patch, instead of just failing with "device already registered" the kernel emits another uevent with CACHED_UUID which would be processed another time to set up a symlink. This patch is not yet upstream, but we will submit it there as well. However, requesting this a SAUCE patch until it lands upstream. This patch has also been submitted for X, A and B. However, Zesty also needs mainlin commit 4b758df21e as a prereq. Commit 4b758df21e was cc'd to upstream stable. However, 4.10 is EOL upstream, so Zesty never got it. == Fix == Patch from Ryan Harper : bcache: decouple emitting a cached_dev CHANGE uevent Also the following commit as a prereq: 4b758df21ee7 ("bcache: Fix leak of bdev reference") == Regression Potential == There is some risk of regression, since this is new code. However, it is limited to the bcache. == Test Case == A test kernel was built with these patches and tested by the original bug reporter. The bug reporter states the test kernel resolved the bug. Jan Kara (1): bcache: Fix leak of bdev reference Ryan Harper (1): bcache: decouple emitting a cached_dev CHANGE uevent drivers/md/bcache/bcache.h | 1 + drivers/md/bcache/super.c | 55 +++++++++++++++++++++++++++++++++++++--------- 2 files changed, 46 insertions(+), 10 deletions(-)