From owner-freebsd-bugs@freebsd.org Thu Jan 21 21:37:36 2021 Return-Path: Delivered-To: freebsd-bugs@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 23A824E073D for ; Thu, 21 Jan 2021 21:37:36 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mailman.nyi.freebsd.org (mailman.nyi.freebsd.org [IPv6:2610:1c1:1:606c::50:13]) by mx1.freebsd.org (Postfix) with ESMTP id 4DMG2S0JP5z3Cyd for ; Thu, 21 Jan 2021 21:37:36 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: by mailman.nyi.freebsd.org (Postfix) id 0A6014E0636; Thu, 21 Jan 2021 21:37:36 +0000 (UTC) Delivered-To: bugs@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 0A2924E073A for ; Thu, 21 Jan 2021 21:37:36 +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 4DMG2R6r0Lz3D1c for ; Thu, 21 Jan 2021 21:37:35 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) 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 DDBF513700 for ; Thu, 21 Jan 2021 21:37:35 +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 10LLbZS8041235 for ; Thu, 21 Jan 2021 21:37:35 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from bugzilla@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 10LLbZpA041234 for bugs@FreeBSD.org; Thu, 21 Jan 2021 21:37:35 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: bugzilla set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 218598] pwait deadlocks on its own pid Date: Thu, 21 Jan 2021 21:37:36 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: bin X-Bugzilla-Version: CURRENT X-Bugzilla-Keywords: patch X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: commit-hook@FreeBSD.org X-Bugzilla-Status: Open X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: bugs@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: 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 MIME-Version: 1.0 X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 21 Jan 2021 21:37:36 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D218598 --- Comment #5 from commit-hook@FreeBSD.org --- A commit in branch main references this bug: URL: https://cgit.FreeBSD.org/src/commit/?id=3D5bdce6ff546e00673f9f515d2165d0290= 1e858aa commit 5bdce6ff546e00673f9f515d2165d02901e858aa Author: Alexander V. Chernikov AuthorDate: 2021-01-21 21:26:15 +0000 Commit: Alexander V. Chernikov CommitDate: 2021-01-21 21:36:37 +0000 Remove deadlock in rc caused by pwait waiting for itself. The following situation can trigger the deadlock: 1) Long time ago a_service was started through rc.d 2) We want to restart a_service and issue service a_service restart 3) rc.subr reads current process PID (via file or process), sends TERM signal and runs pwait with PID harvested 4) a_service process dies very quickly so it's PID becomes available. It is possible that while original process was running, PID counter overflowed and pwait got assigned a_service's PID. This patch ignores pid(s) to wait that are equal to pwait PID. Reported by: Dan McGregor, Boris Lytochkin Submitted by: Boris Lytochkin Reviewed By: 0mp MFC after: 2 weeks PR: 218598 Differential Revision: https://reviews.freebsd.org/D28240 bin/pwait/pwait.1 | 6 +++++- bin/pwait/pwait.c | 4 ++++ 2 files changed, 9 insertions(+), 1 deletion(-) --=20 You are receiving this mail because: You are the assignee for the bug.=