From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boaz Harrosh Subject: Re: ramdisk problems in 4.0-rc1? (was Re: [PATCH 1/4] xfs/104: log size too small for 4k sector drives) Date: Sun, 01 Mar 2015 10:27:49 +0200 Message-ID: <54F2CD85.3060303@plexistor.com> References: <1424818479-10083-1-git-send-email-david@fromorbit.com> <1424818479-10083-2-git-send-email-david@fromorbit.com> <20150225161151.GC28053@bfoster.bfoster> <20150225223248.GH4251@dastard> <20150225233115.GA1009@bfoster.bfoster> <20150225234343.GI4251@dastard> <54EECF53.8010207@plexistor.com> <20150227005837.GG18360@dastard> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: Brian Foster , fstests@vger.kernel.org, linux-fsdevel@vger.kernel.org, axboe@fb.com To: Dave Chinner Return-path: Received: from mail-we0-f171.google.com ([74.125.82.171]:42171 "EHLO mail-we0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750956AbbCAI1w (ORCPT ); Sun, 1 Mar 2015 03:27:52 -0500 Received: by wesw62 with SMTP id w62so27724174wes.9 for ; Sun, 01 Mar 2015 00:27:51 -0800 (PST) In-Reply-To: <20150227005837.GG18360@dastard> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On 02/27/2015 02:58 AM, Dave Chinner wrote: <> >> >> Sigh, thanks Dave. Yes you are correct my patch enabled the >> udev events, as part of fixing ramdisk with partitions. >> This is because if you do not enable them then mount by UUID >> and all sort of lsblk and friends do not work. > > Sure, that's what the gendisk abstraction just you. But why am I > seeing random partition probes on a ramdisk that *isn't using > partitions*? > Yes, There should be the one new event on create (modprobe or mknod) which was not there before. Perhaps it triggers a systemd process that never used to run before. (And is now sitting there and making a mess) <> >> It looks like the system anticipates that ramdisk "should >> not have these events" > > Right, but not because it's a ramdisk. Those events should not be > occurring because I'm not creating or destroying devices, I'm not > changing partition tables, I'm not resizing ramdisks or partitions, > and so on. I'm simply mkfs'ing, mounting and unmounting filesystems > on the ramdisks - nothing should be generating device based udev > events... > > Finding the trigger that is causing these events will tell us what > the bug is - > restricting the config won't help, especially as DAX > will *always* be enabled on my test machines as it's something > needed in my test matrix. No the "if DAX" is for the 4k thing. The enablement of the uevents is with a new "part_show" module parameter (See patch-1). > I'm not sure how to go about finding that > trigger right now and as such I won't really have time to look at it > until after lsfmm/vault... > I'll try to reproduce this here. What Fedora version do I need? > Cheers, > Dave. > Thanks Boaz