From owner-freebsd-bugs@freebsd.org Sun Sep 15 14:12:50 2019 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 6EFD5EE12B for ; Sun, 15 Sep 2019 14:12:50 +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 46WWYG2P4sz4N35 for ; Sun, 15 Sep 2019 14:12:50 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: by mailman.nyi.freebsd.org (Postfix) id 5056BEE128; Sun, 15 Sep 2019 14:12:50 +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 5016EEE127 for ; Sun, 15 Sep 2019 14:12:50 +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 46WWYG1Vznz4N34 for ; Sun, 15 Sep 2019 14:12:50 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 179699588 for ; Sun, 15 Sep 2019 14:12:50 +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 x8FECnOc073586 for ; Sun, 15 Sep 2019 14:12:49 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id x8FECngI073585 for bugs@FreeBSD.org; Sun, 15 Sep 2019 14:12:49 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 239973] Kernel Panic: device_get_ivars(9) returns NULL which leads to Null pointer dereference for multiple drivers Date: Sun, 15 Sep 2019 14:12:49 +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: CURRENT X-Bugzilla-Keywords: panic, patch X-Bugzilla-Severity: Affects Many People X-Bugzilla-Who: neerajpal09@gmail.com X-Bugzilla-Status: New 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: 2.1.29 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 15 Sep 2019 14:12:50 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D239973 --- Comment #3 from Neeraj --- (In reply to Hans Petter Selasky from comment #2) yeah you right. Actually, as per the discussion going in the mailing list, other developers said that the patch is correct *if and only if want to preserve the ivars information* and preserving the info would be a long term solution. But, as you said that there might be a race, that devctl is=20 attaching/detaching drivers while USB is doing the same, it might go into t= he panic due to that. So, you are correct on the point that USB drivers are not supposed to be managed outside the USB enumeration thread. Using devctl on USB driver is n= ot supported. Only usbconfig is allowed to attach/detach USB devices. And, I also think that it is a better solution to blacklist devctl from touching USB device nodes or anything that parents to a usbusX, instead of patching all the devices. As, we already have usbconfig to do the same. --=20 You are receiving this mail because: You are the assignee for the bug.=