From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout-p-201.mailbox.org (mout-p-201.mailbox.org [80.241.56.171]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 494BC44E66A for ; Wed, 2 Sep 2026 11:40:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=80.241.56.171 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788349204; cv=none; b=MqzC62oanMdVWeW+t8dHjFIrV4QJN/3ZUKYCa1u44pKTtfQKXenxvQdlrajaAw3vxkvuo1tYSPfRgKFiZTW6amrkw37OGKhjwBCYW7+hjgcAmvPsboltOLZeeazden1ipyYYFQ8hqkL0qClZxbcJLMdri6nDPDxMpq3fZryMn8I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788349204; c=relaxed/simple; bh=qeioP7kdKjSkEbC9pe1QvQNugDjO5/Ci79J3J4FzbD0=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=iwlrirPuhncWskvOpGMO3a99GY2BqKPpPLU1IhJivS5PwEwkJdWw5QJeRX0k+5oYHjpgURwLSZAlqzVMLJONscQDH0ze9rKF++3oYVvBh52V27Ub9/jteH8K3P5kSLHjFP4Jb1Sp60UGEVRFdYpO46IX3nFkOyl1Ybc7mfox5pk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=mailbox.org; spf=pass smtp.mailfrom=mailbox.org; dkim=pass (2048-bit key) header.d=mailbox.org header.i=@mailbox.org header.b=Dnwhez2W; arc=none smtp.client-ip=80.241.56.171 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=mailbox.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mailbox.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=mailbox.org header.i=@mailbox.org header.b="Dnwhez2W" Received: from smtp1.mailbox.org (smtp1.mailbox.org [IPv6:2001:67c:2050:b231:465::1]) (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) (No client certificate requested) by mout-p-201.mailbox.org (Postfix) with ESMTPS id 4hZgkd3ps7zMlHD; Wed, 02 Sep 2026 13:39:53 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mailbox.org; s=mail20150812; t=1788349193; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=qeioP7kdKjSkEbC9pe1QvQNugDjO5/Ci79J3J4FzbD0=; b=Dnwhez2W0X3MWUfGgeBRfg9Jj1zXhk7WZ/xnBicud/yXVF2Vj6aQLzqs8AU1gWVtVBTtmq pmOcFdpBY+qT9KATsbhAKBNgKYz5brr8+VFLNkXjxp0BjuHZGdBMECNReeZnPjc6Vn/KFV V6VxfdQ4uy69btSsptn7BNrLP0a61aLjuwT+q5OkzBr26IKA2Ve2+XlK8bwndh0wpj45Hk tcaNKCxLDW7bDJLR1W4IDsxVEXYFNQTO4Dahjy9Ux2xrmRh3Y0077PttK2brVLdTiBwUR6 Kavcm6IrHcQDjR6+HqNQPnLwLuGtVhahgTR8/80TxCWf49HqtAm71jQTkXuKzQ== Message-ID: <95e34a8771fe827e134970a3580ceeb5f661a40d.camel@mailbox.org> Subject: Re: [PATCH v1 1/2] drm/sched: cache the timeline name to fix a use-after-free From: Philipp Stanner Reply-To: phasta@kernel.org To: Tvrtko Ursulin , phasta@kernel.org, =?UTF-8?Q?=EA=B9=80=EC=A2=85=ED=98=81?= , matthew.brost@intel.com, dakr@kernel.org Cc: christian.koenig@amd.com, ckoenig.leichtzumerken@gmail.com, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Date: Wed, 02 Sep 2026 13:39:49 +0200 In-Reply-To: <619669b6-69ea-4aa5-b91e-b29cc788e335@ursulin.net> References: <8c2a4df5-37a4-414e-81e2-cd97218e5355@ursulin.net> <619669b6-69ea-4aa5-b91e-b29cc788e335@ursulin.net> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MBO-RS-ID: 5673802fd2592c4cf56 X-MBO-RS-META: 1w5cme4y615edbk8oiwca3ok9w5rubca On Wed, 2026-09-02 at 11:20 +0100, Tvrtko Ursulin wrote: >=20 > To collate two replies in one: >=20 > On 02/09/2026 11:07, Philipp Stanner wrote: >=20 > >=20 > > The issue here IMO is that we are discussing working around an issue > > that actually stems from dma_fence not being consistently synchronized, > > notably because of the ops->release callback being implemented. > >=20 > > ops->release is de facto deprecated, precisely for reasons like these. > >=20 > > If we could get rid of it for sched_fence, dma_fence would take care of > > the decoupling of the name callbacks. > >=20 > > So that appears worth investigating from my POV. >=20 > I completely agree here but I am just not sure how feasible that would= =20 > be. We may accept to live with the cross-documentation workaround at=20 > least as a start since even if feasible it could be a lot of work to=20 > change sched_fence like that. It should be enough to remove ops->release for the finished_fence for now, since that's the one typically (always?) shared with userspace. All that release cb does is drop yet another reference. I think it's worth an investigation. Maybe =EA=B9=80=EC=A2=85=ED=98=81 can = give it a look? P.