From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olivier Brunel Subject: Re: bpfilter causes a leftover kernel process Date: Tue, 28 Aug 2018 13:23:38 +0200 Message-ID: <20180828132338.6995e445@jjacky.com> References: <20180826180816.04ef7d16@jjacky.com> <20180827183122.0b4ac65e@jjacky.com> <20180828033500.g3siwst5h2ckewwb@ast-mbp> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Cc: netdev@vger.kernel.org, daniel@iogearbox.net To: Alexei Starovoitov Return-path: Received: from mail.jjacky.com ([23.29.69.116]:43907 "EHLO mail.jjacky.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727506AbeH1POM (ORCPT >); Tue, 28 Aug 2018 11:14:12 -0400 In-Reply-To: <20180828033500.g3siwst5h2ckewwb@ast-mbp> Sender: netdev-owner@vger.kernel.org List-ID: On Mon, 27 Aug 2018 20:35:02 -0700 Alexei Starovoitov wrote: > I'm also running Arch Linux in my VM, but I'm not able to reproduce > umount issue. I'm guessing it's somehow related to non-static build > and libc.so being busy with old systemd. Oh, I mentioned it in a previous draft of my original mail but it seems it got lost in rewrites, I don't actually use systemd. Not that it should matter here though. > Typical shutdown should have done: > [ 73.498022] shutdown[1]: Sending SIGTERM to remaining processes... > [ 73.505501] shutdown[1]: Sending SIGKILL to remaining processes... > [ 73.512783] shutdown[1]: Unmounting file systems. > And at the time of umount / no processes are alive other than systemd. Yeah, I have a similar thing happening on shutdown, except that we're talking about a kernel thread here, so that process is ignored by the mentionned killing spree as a result, thus leaving that process running. >>From a shell opened after the umounting fails I can see that only my pid1 & the opened shell are running, except of course that this bpfilter process is there, as a kernel thread "[none]" Manually killing it at that point works, i.e. allows the umounting to succeed and a proper shutdown to complete.