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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EE571C43334 for ; Mon, 13 Jun 2022 11:53:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1357190AbiFMLxL (ORCPT ); Mon, 13 Jun 2022 07:53:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55938 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1356657AbiFMLux (ORCPT ); Mon, 13 Jun 2022 07:50:53 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 87DA8D10E; Mon, 13 Jun 2022 03:55:01 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 23FEC60EFE; Mon, 13 Jun 2022 10:55:01 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 37910C34114; Mon, 13 Jun 2022 10:55:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1655117700; bh=lwGUoTqvlgocRTw2hxr/X5mUBTGEKQRqVn9MQ8udl2o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UZVbbpj1VeNaE3bqq+/AwrNxwplCR0WO0wqneXbwPpaTVBUOjXoC1QDB6nhMf6BlL QJVO95jJrNF78H44nmyd411LriZNGmJCotfgSX60DIOq2MiC5haSdeUv2TGTYBKlE5 khjaQPP7IqqOFUbJ8OI7F0t8fCGLyFmGLgrgsMdY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tomeu Vizoso , Jessica Zhang , Rob Clark , Dmitry Baryshkov , Sasha Levin Subject: [PATCH 4.19 088/287] drm/msm/mdp5: Return error code in mdp5_pipe_release when deadlock is detected Date: Mon, 13 Jun 2022 12:08:32 +0200 Message-Id: <20220613094926.546323454@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220613094923.832156175@linuxfoundation.org> References: <20220613094923.832156175@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jessica Zhang [ Upstream commit d59be579fa932c46b908f37509f319cbd4ca9a68 ] mdp5_get_global_state runs the risk of hitting a -EDEADLK when acquiring the modeset lock, but currently mdp5_pipe_release doesn't check for if an error is returned. Because of this, there is a possibility of mdp5_pipe_release hitting a NULL dereference error. To avoid this, let's have mdp5_pipe_release check if mdp5_get_global_state returns an error and propogate that error. Changes since v1: - Separated declaration and initialization of *new_state to avoid compiler warning - Fixed some spelling mistakes in commit message Changes since v2: - Return 0 in case where hwpipe is NULL as this is considered normal behavior - Added 2nd patch in series to fix a similar NULL dereference issue in mdp5_mixer_release Reported-by: Tomeu Vizoso Signed-off-by: Jessica Zhang Fixes: 7907a0d77cb4 ("drm/msm/mdp5: Use the new private_obj state") Reviewed-by: Rob Clark Reviewed-by: Dmitry Baryshkov Patchwork: https://patchwork.freedesktop.org/patch/485179/ Link: https://lore.kernel.org/r/20220505214051.155-1-quic_jesszhan@quicinc.com Signed-off-by: Dmitry Baryshkov Signed-off-by: Sasha Levin --- drivers/gpu/drm/msm/disp/mdp5/mdp5_pipe.c | 15 +++++++++++---- drivers/gpu/drm/msm/disp/mdp5/mdp5_pipe.h | 2 +- drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c | 20 ++++++++++++++++---- 3 files changed, 28 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_pipe.c b/drivers/gpu/drm/msm/disp/mdp5/mdp5_pipe.c index 1ef26bc63163..88de12225582 100644 --- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_pipe.c +++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_pipe.c @@ -130,18 +130,23 @@ int mdp5_pipe_assign(struct drm_atomic_state *s, struct drm_plane *plane, return 0; } -void mdp5_pipe_release(struct drm_atomic_state *s, struct mdp5_hw_pipe *hwpipe) +int mdp5_pipe_release(struct drm_atomic_state *s, struct mdp5_hw_pipe *hwpipe) { struct msm_drm_private *priv = s->dev->dev_private; struct mdp5_kms *mdp5_kms = to_mdp5_kms(to_mdp_kms(priv->kms)); struct mdp5_global_state *state = mdp5_get_global_state(s); - struct mdp5_hw_pipe_state *new_state = &state->hwpipe; + struct mdp5_hw_pipe_state *new_state; if (!hwpipe) - return; + return 0; + + if (IS_ERR(state)) + return PTR_ERR(state); + + new_state = &state->hwpipe; if (WARN_ON(!new_state->hwpipe_to_plane[hwpipe->idx])) - return; + return -EINVAL; DBG("%s: release from plane %s", hwpipe->name, new_state->hwpipe_to_plane[hwpipe->idx]->name); @@ -152,6 +157,8 @@ void mdp5_pipe_release(struct drm_atomic_state *s, struct mdp5_hw_pipe *hwpipe) } new_state->hwpipe_to_plane[hwpipe->idx] = NULL; + + return 0; } void mdp5_pipe_destroy(struct mdp5_hw_pipe *hwpipe) diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_pipe.h b/drivers/gpu/drm/msm/disp/mdp5/mdp5_pipe.h index bb2b0ac7aa2b..072db6a99b85 100644 --- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_pipe.h +++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_pipe.h @@ -48,7 +48,7 @@ int mdp5_pipe_assign(struct drm_atomic_state *s, struct drm_plane *plane, uint32_t caps, uint32_t blkcfg, struct mdp5_hw_pipe **hwpipe, struct mdp5_hw_pipe **r_hwpipe); -void mdp5_pipe_release(struct drm_atomic_state *s, struct mdp5_hw_pipe *hwpipe); +int mdp5_pipe_release(struct drm_atomic_state *s, struct mdp5_hw_pipe *hwpipe); struct mdp5_hw_pipe *mdp5_pipe_init(enum mdp5_pipe pipe, uint32_t reg_offset, uint32_t caps); diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c b/drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c index 3d8eaa25bea0..501d7989b9a5 100644 --- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c +++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_plane.c @@ -402,12 +402,24 @@ static int mdp5_plane_atomic_check_with_state(struct drm_crtc_state *crtc_state, mdp5_state->r_hwpipe = NULL; - mdp5_pipe_release(state->state, old_hwpipe); - mdp5_pipe_release(state->state, old_right_hwpipe); + ret = mdp5_pipe_release(state->state, old_hwpipe); + if (ret) + return ret; + + ret = mdp5_pipe_release(state->state, old_right_hwpipe); + if (ret) + return ret; + } } else { - mdp5_pipe_release(state->state, mdp5_state->hwpipe); - mdp5_pipe_release(state->state, mdp5_state->r_hwpipe); + ret = mdp5_pipe_release(state->state, mdp5_state->hwpipe); + if (ret) + return ret; + + ret = mdp5_pipe_release(state->state, mdp5_state->r_hwpipe); + if (ret) + return ret; + mdp5_state->hwpipe = mdp5_state->r_hwpipe = NULL; } -- 2.35.1