From nobody Thu Apr 2 12:50:40 2026 X-Original-To: current@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 4fmhXz3vrkz6YQGw for ; Thu, 02 Apr 2026 12:50:43 +0000 (UTC) (envelope-from david@catwhisker.org) Received: from mx.catwhisker.org (mx.catwhisker.org [107.204.234.170]) (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 4fmhXy1DN0z3bg7 for ; Thu, 02 Apr 2026 12:50:42 +0000 (UTC) (envelope-from david@catwhisker.org) Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=pass (mx1.freebsd.org: domain of david@catwhisker.org designates 107.204.234.170 as permitted sender) smtp.mailfrom=david@catwhisker.org Received: from albert.catwhisker.org (localhost [127.0.0.1]) by albert.catwhisker.org (8.18.1/8.18.1) with ESMTP id 632CoeOb070008 for ; Thu, 2 Apr 2026 12:50:40 GMT (envelope-from david@albert.catwhisker.org) Received: (from david@localhost) by albert.catwhisker.org (8.18.1/8.18.1/Submit) id 632CoeqA070007 for current@freebsd.org; Thu, 2 Apr 2026 05:50:40 -0700 (PDT) (envelope-from david) Date: Thu, 2 Apr 2026 05:50:40 -0700 From: David Wolfskill To: current@freebsd.org Subject: Panic: "knote ... was already on knlist..." after main-n284826-d9d7b5948649 Message-ID: Reply-To: current@freebsd.org Mail-Followup-To: current@freebsd.org List-Id: Discussions about the use of FreeBSD-current List-Archive: https://lists.freebsd.org/archives/freebsd-current List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-current@FreeBSD.org MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="U+T5Ac6OxCViu+EV" Content-Disposition: inline X-Spamd-Result: default: False [-0.36 / 15.00]; REPLYTO_EQ_TO_ADDR(5.00)[]; SIGNED_PGP(-2.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; NEURAL_HAM_SHORT(-0.96)[-0.958]; R_SPF_ALLOW(-0.20)[+ip4:107.204.234.170]; MIME_GOOD(-0.20)[multipart/signed,text/plain]; DMARC_NA(0.00)[catwhisker.org]; RCPT_COUNT_ONE(0.00)[1]; ARC_NA(0.00)[]; RCVD_TLS_LAST(0.00)[]; MISSING_XM_UA(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; REPLYTO_DOM_NEQ_FROM_DOM(0.00)[]; FREEFALL_USER(0.00)[david]; FROM_HAS_DN(0.00)[]; MIME_TRACE(0.00)[0:+,1:+,2:~]; TO_DN_NONE(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; FROM_EQ_ENVFROM(0.00)[]; ASN(0.00)[asn:7018, ipnet:107.192.0.0/12, country:US]; PREVIOUSLY_DELIVERED(0.00)[current@freebsd.org]; MLMMJ_DEST(0.00)[current@freebsd.org]; MID_RHS_MATCH_FROMTLD(0.00)[]; R_DKIM_NA(0.00)[]; HAS_REPLYTO(0.00)[current@freebsd.org] X-Rspamd-Queue-Id: 4fmhXy1DN0z3bg7 X-Spamd-Bar: / --U+T5Ac6OxCViu+EV Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Build machine (kernel GENERIC) did not experience this. So far, 3 out of 3 laptops have (the 4th one has yet to finish the build). I snapped a photo, which is up at https://www.catwhisker.org/~david/FreeBSD/head/n284826/screen.jpg The panic occurs during the late(r) part of the transition to multi-user mode. I am happy to poke at one of the machines, given suitable clues: I tend to break stuff. The machines had previously built and run main-n284804-f3b59bf28504. All machines are amd64, and I use PORTS_MODULES in /etc/src.conf to ensure that ports-resident kernel modules get rebuilt whenever the kernel does./~david/FreeBSD/head/n284826/screen.jpg The panic occurs during the late(r) part of the transition to multi-user mode. I am happy to poke at one of the machines, given suitable clues: I tend to break stuff. A quick scan down the backtrace shows: db_trace_self_wrapper() vpanic() panic() knlist_remove() kqueue_fork_copy_list() kqueue_fork() fdcopy() do_fork() fork() sys_fork() amd64_syscall() fast_syscall_common() --- syscall KDB: enter: panic [ thread pid 1891 tld 100578 ] Stopped at xffffffffff88c177c3 =3D kdb_enter+0x33: movq $0,0x15f7842(%rip) db>=20 The machines had previously built and run main-n284804-f3b59bf28504. All machines are amd64, and I use PORTS_MODULES in /etc/src.conf to ensure that ports-resident kernel modules get rebuilt whenever the kernel does. Oh -- the 4th laptop also panicked (apparently similarly). The older 3 laptops use custom kernels, but the newest one (which uses ZFS & boot environments; the oolder ones do not) uses a GENERIC kernel (as the build machine does). Peace, david --=20 David H. Wolfskill david@catwhisker.org See https://www.catwhisker.org/~david/publickey.gpg for my public key. --U+T5Ac6OxCViu+EV Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- iNUEARYKAH0WIQRCec5RsK7Enudh3yGB9MJ9AwUELQUCac5mIF8UgAAAAAAuAChp c3N1ZXItZnByQG5vdGF0aW9ucy5vcGVucGdwLmZpZnRoaG9yc2VtYW4ubmV0NDI3 OUNFNTFCMEFFQzQ5RUU3NjFERjIxODFGNEMyN0QwMzA1MDQyRAAKCRCB9MJ9AwUE LSE+AP4nXODDVhiGzAwL/jd9fE8jnp2THcVqzP5g8Iv/O4haXgEAqoGrAFw0nKia Ue3g2m6yqWu/kaszQU5wEZZ+q/D05Ao= =R5P2 -----END PGP SIGNATURE----- --U+T5Ac6OxCViu+EV--