From nobody Wed Dec 13 01:37:32 2023 X-Original-To: fs@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 4SqdQN5wwSz53dJk for ; Wed, 13 Dec 2023 01:37:32 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (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-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4SqdQN3xyLz4V8G for ; Wed, 13 Dec 2023 01:37:32 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1702431452; a=rsa-sha256; cv=none; b=ZSRWSrkX9FmvzbmtH0sXmd7zbfkEA18T7RHJoaOB2DJSfcJvg7aOQ2mMfIeY8NXXycmPGX 4/zvH2SK9qrb1k3g6QhsFKbGWBk3imAHAI8Mfrxu0ji925Jiz6x+3aVzfo5oCHSnsuMq0b scLCQXwfwWlygn+IfmPUzMYt9sjrMR2R9LGs9BC9Zpc62Mczfnn1+MaX44OmCm8l9/2t2c AcG+Xip2ybe60eQHwt8Tx4dmS7XRy97SoQj0aYvqpQcw5GzSE+w7/HlZNnenc+iIYJuums gOBGJffZTEp1EqT3U5bDqNosRQhVSQUToC0Xho48wyVPaLrJBGEpeWojMrYOOQ== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1702431452; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=mrXgfaPgdQDRuuiyqK1jw9saRmrCN1Ky/dHMvt2i1IQ=; b=ZrvD1scB0cvsXZRV491I28OvKJLNoMThehHFtxqe0GBq0xaACFzdCF9zZPYg5SvuoTEONy 5PUMXkE6fHp1FEQD7tIRjyMnKtgkHND2q18lFpHMOG8B8jtKrRi5J0WVu3TVlSu9XbwKmB teLHfay4izFlmI1vJzhmYUD96K9WnhfocxmIsXXL1f9UWBkQnurrj1Ij5ZD7nmwNwOW/pC fIvzrtzFKfF7PyxZame87pio77mhdBHV3f9zUdi8ONrGx8hU25IMkffru3XjIJjJZsB29s UFoywetyB4FnmZNuQjYoh13b4V50L7vAU6uKOpniqcyxdPewPRVyyVXHy+4TYg== Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (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 mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4SqdQN33HPzfFl for ; Wed, 13 Dec 2023 01:37:32 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.5]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id 3BD1bWHk053013 for ; Wed, 13 Dec 2023 01:37:32 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 3BD1bWss053012 for fs@FreeBSD.org; Wed, 13 Dec 2023 01:37:32 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: fs@FreeBSD.org Subject: [Bug 275570] self-referential nullfs mount over tmpfs in combination with MNT_UPDATE results in a hang Date: Wed, 13 Dec 2023 01:37:32 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 14.0-RELEASE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: kevans@freebsd.org X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: fs@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: cc Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated List-Id: Filesystems List-Archive: https://lists.freebsd.org/archives/freebsd-fs List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-fs@freebsd.org MIME-Version: 1.0 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D275570 Kyle Evans changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |dfr@FreeBSD.org, | |kevans@freebsd.org --- Comment #1 from Kyle Evans --- Let's start with dfr@, since the sample in question is specifically null-mounting a file over itself. With the deadlock.c attached, I hit it best with a stupid simple loop: ``` #!/bin/sh iteration=3D1 while true; do echo "Iteration $iteration" ./a.out iteration=3D$((iteration + 1)) done ``` Took me about 15 tries. When it deadlocks on my machine, it's in the nmount= (2) that would be null-mounting the file over itself rather than the follow-up MNT_UPDATE of the tmpfs mount holding it. --=20 You are receiving this mail because: You are the assignee for the bug.=