From owner-freebsd-bugs@freebsd.org Tue Mar 24 23:15:34 2020 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 02BE326D8A7 for ; Tue, 24 Mar 2020 23:15:34 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mailman.nyi.freebsd.org (unknown [127.0.1.3]) by mx1.freebsd.org (Postfix) with ESMTP id 48n6YK1vkCz4Cvs for ; Tue, 24 Mar 2020 23:15:33 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: by mailman.nyi.freebsd.org (Postfix) id B54E626D8A6; Tue, 24 Mar 2020 23:15:24 +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 A8FDE26D8A5 for ; Tue, 24 Mar 2020 23:15:24 +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) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 48n6Y54sqbz4Cs6 for ; Tue, 24 Mar 2020 23:15:21 +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) server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 673157F89 for ; Tue, 24 Mar 2020 23:15:13 +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 02ONFDYh095820 for ; Tue, 24 Mar 2020 23:15:13 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 02ONFDNq095819 for bugs@FreeBSD.org; Tue, 24 Mar 2020 23:15:13 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: bugs@FreeBSD.org Subject: [Bug 244878] Kernel panic due to spin lock held too long Date: Tue, 24 Mar 2020 23:15:12 +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: 12.1-RELEASE X-Bugzilla-Keywords: crash, needs-qa X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: jah@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: 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 MIME-Version: 1.0 X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 24 Mar 2020 23:15:34 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D244878 Jason A. Harmening changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |jah@FreeBSD.org --- Comment #3 from Jason A. Harmening --- Not a lot to go on from the backtrace. One thing that can cause this pani= c is if a thread calls smp_rendezvous_cpus() with local interrupts disabled: if another thread holds smp_ipi_mtx and is trying to IPI the first thread's CP= U, the two threads can livelock. It doesn't look like the timer callout+in6 route expiration path that panic= ked should ever call smp_rendezvous_cpus() with interrupts disabled, but I think it's also possible that this thread could have been the victim of two other threads that were livelocked. r357308 added a check to HEAD (INVARIANTS kernels only) that panics if a th= read enters smp_rendezvous_cpus() with interrupts disabled. If this is at all reproducible, it might be worth trying a kernel with that check backported. Also worth noting: in6_mtutimo() was completely removed from HEAD in 355888. --=20 You are receiving this mail because: You are the assignee for the bug.=