From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kai Krakow Subject: Re: make-bcache bug? Date: Mon, 15 May 2017 20:37:45 +0200 Message-ID: <20170515203745.4fc14030@jupiter.sol.kaishome.de> References: <20170514175840.s3l6p4zjxnf2brm6@merlins.org> <20170514220055.2d06210e@jupiter.sol.kaishome.de> <20170514201940.76bu7rz764jeplnd@merlins.org> <20170514232816.79c2530e@jupiter.sol.kaishome.de> <8737c6th8m.fsf@esperi.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Received: from [195.159.176.226] ([195.159.176.226]:44076 "EHLO blaine.gmane.org" rhost-flags-FAIL-FAIL-OK-OK) by vger.kernel.org with ESMTP id S932948AbdEOSh4 (ORCPT ); Mon, 15 May 2017 14:37:56 -0400 Received: from list by blaine.gmane.org with local (Exim 4.84_2) (envelope-from ) id 1dAKsN-0001y2-7B for linux-bcache@vger.kernel.org; Mon, 15 May 2017 20:37:47 +0200 Sender: linux-bcache-owner@vger.kernel.org List-Id: linux-bcache@vger.kernel.org To: linux-bcache@vger.kernel.org Am Mon, 15 May 2017 13:52:09 +0100 schrieb Nix : > On 14 May 2017, Kai Krakow said: > > I had done this previously, too, and had no such message. But I had > > to use wipefs anyway because otherwise udev came and triggered the > > device for reasons I couldn't really follow. > > udev does a blkid to see how the block device needs to be activated: > this relies on precisely the information wipefs removes. Avoiding this > problem is why wipefs *exists*. :) Yes, but something triggered udev when it shouldn't... This ends up in unregistering/stopping the bcache, then wipefs the cdev, then look if udev was triggered and eventually stop it again. I guess everytime I ran "fdisk -l" to double-check the devices, or "lsblk", or "blkid", udev was triggered and re-enabled the bcache. This is a race you cannot win. ;-) -- Regards, Kai Replies to list-only preferred.