From nobody Sun Feb 1 21:18:53 2026 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4f42gH73l2z6QglQ; Sun, 01 Feb 2026 21:19:07 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4f42gH39FWz4QRf; Sun, 01 Feb 2026 21:19:07 +0000 (UTC) (envelope-from kostikbel@gmail.com) Authentication-Results: mx1.freebsd.org; none Received: from tom.home (kib@localhost [127.0.0.1] (may be forged)) by kib.kiev.ua (8.18.1/8.18.1) with ESMTP id 611LIr71035387; Sun, 1 Feb 2026 23:18:56 +0200 (EET) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.10.3 kib.kiev.ua 611LIr71035387 Received: (from kostik@localhost) by tom.home (8.18.1/8.18.1/Submit) id 611LIrsR035386; Sun, 1 Feb 2026 23:18:53 +0200 (EET) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Sun, 1 Feb 2026 23:18:53 +0200 From: Konstantin Belousov To: Gleb Popov Cc: Alan Somers , src-committers@freebsd.org, dev-commits-src-all@freebsd.org, dev-commits-src-main@freebsd.org Subject: Re: git: 10037d0978f8 - main - fusefs: Implement support for the auto_unmount option kernel-side Message-ID: References: <697499a8.335a0.2e12eda1@gitrepo.freebsd.org> List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-all@freebsd.org Sender: owner-dev-commits-src-all@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Spam-Status: No, score=-1.0 required=5.0 tests=ALL_TRUSTED,BAYES_00, DKIM_ADSP_CUSTOM_MED,FORGED_GMAIL_RCVD,FREEMAIL_FROM, NML_ADSP_CUSTOM_MED autolearn=no autolearn_force=no version=4.0.2 X-Spam-Checker-Version: SpamAssassin 4.0.2 (2025-08-27) on tom.home X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:6939, ipnet:2001:470::/32, country:US] X-Rspamd-Queue-Id: 4f42gH39FWz4QRf X-Spamd-Bar: ---- On Sun, Feb 01, 2026 at 10:27:41PM +0300, Gleb Popov wrote: > On Sun, Jan 25, 2026 at 10:39 PM Konstantin Belousov > wrote: > > > > > > > + vfs_ref(fdata->mp); > > Don't you need to take the reference when the fdata is created and mp member > > is initialized, and not here? > > > > What guarantees that the mp is still ours? > > In fact, I think that you should use vfs_busy() and not vfs_ref(), > > since what prevents mp from being unmounted under us? > > Using vfs_busy() before dounmount() results in a soft hang: > - vfs_busy increments mp->mnt_lockref in > https://github.com/freebsd/freebsd-src/blob/98bdf63f6e94be42a1787de73608de15bcb3419a/sys/kern/vfs_subr.c#L929 > - dounmount spins until mp->mnt_lockref becomes 0 in > https://github.com/freebsd/freebsd-src/blob/98bdf63f6e94be42a1787de73608de15bcb3419a/sys/kern/vfs_mount.c#L2318-L2322 > > This results in a FUSE process to hang in the "mount drain" state. Ok, change it to the mnt_ref() done when assigning to fdata->mp for now, please.