From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E0E83C433F5 for ; Fri, 10 Dec 2021 10:30:17 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 68BFC10E535; Fri, 10 Dec 2021 10:30:17 +0000 (UTC) Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by gabe.freedesktop.org (Postfix) with ESMTPS id 56AA610E535; Fri, 10 Dec 2021 10:30:16 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10193"; a="301706704" X-IronPort-AV: E=Sophos;i="5.88,195,1635231600"; d="scan'208";a="301706704" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Dec 2021 02:30:15 -0800 X-IronPort-AV: E=Sophos;i="5.88,195,1635231600"; d="scan'208";a="517179939" Received: from mpcorrig-mobl1.ger.corp.intel.com (HELO localhost) ([10.252.4.173]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Dec 2021 02:30:08 -0800 From: Jani Nikula To: Tvrtko Ursulin , Daniele Ceraolo Spurio , Matthew Brost , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, Rodrigo Vivi In-Reply-To: <439fb357-cdda-2996-bb63-eaf41a7fe4d1@linux.intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20211209184814.21125-1-matthew.brost@intel.com> <439fb357-cdda-2996-bb63-eaf41a7fe4d1@linux.intel.com> Date: Fri, 10 Dec 2021 12:30:01 +0200 Message-ID: <877dcc3g7q.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Intel-gfx] [PATCH] drm/i915/guc: Use correct context lock when callig clr_context_registered X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Fri, 10 Dec 2021, Tvrtko Ursulin wrote: > On 09/12/2021 19:14, Daniele Ceraolo Spurio wrote: >>=20 >>=20 >> On 12/9/2021 10:48 AM, Matthew Brost wrote: >>> s/ce/cn/ when grabbing guc_state.lock before calling >>> clr_context_registered. >>> >>> Fixes: 0f7976506de61 ("drm/i915/guc: Rework and simplify locking") >>> Signed-off-by: Matthew Brost >>> Cc: > > I think Cc: stable is not needed here: > > $ git tag --contains 0f7976506de61 > drm-intel-fixes-2021-11-18 > drm-intel-gt-next-2021-10-08 > drm-intel-gt-next-2021-10-21 > drm-intel-gt-next-2021-11-22 > drm-intel-next-2021-10-15 > drm-intel-next-fixes-2021-11-09 > v5.16-rc1 > v5.16-rc2 > v5.16-rc3 > v5.16-rc4 'dim fixes 0f7976506de61' concurs. BR, Jani. > > So still can hit 5.16 via fixes. Rodrigo, did I get this right and you=20 > will be able to pick it up next week or so? > >> Reviewed-by: Daniele Ceraolo Spurio >>=20 >> I'm assuming we didn't see any splat from the lockdep assert in=20 >> clr_context_registered in our CI runs because we never hit this case as= =20 >> it requires 64k+ contexts. Maybe we can add a selftest to purposely=20 >> exercise this path? Not a blocker for merging this fix. > > Was the bug found by inspection or reported? > > Given the buggy function is called steal_guc_id, so if the implication=20 > is there is no testing for guc id stealing, then it indeed please add=20 > some coverage ASAP. > > Regards, > > Tvrtko > >>=20 >> Daniele >>=20 >>> --- >>> =C2=A0 drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 4 ++-- >>> =C2=A0 1 file changed, 2 insertions(+), 2 deletions(-) >>> >>> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c=20 >>> b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c >>> index 1f9d4fde421f..9b7b4f4e0d91 100644 >>> --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c >>> +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c >>> @@ -1937,9 +1937,9 @@ static int steal_guc_id(struct intel_guc *guc,=20 >>> struct intel_context *ce) >>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 list_del_init(&c= n->guc_id.link); >>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 ce->guc_id =3D c= n->guc_id; >>> -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 spin_lock(&ce->guc_state.lo= ck); >>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 spin_lock(&cn->guc_state.lo= ck); >>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 clr_context_regi= stered(cn); >>> -=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 spin_unlock(&ce->guc_state.= lock); >>> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 spin_unlock(&cn->guc_state.= lock); >>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 set_context_guc_= id_invalid(cn); >>=20 --=20 Jani Nikula, Intel Open Source Graphics Center