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 74935C43334 for ; Tue, 7 Jun 2022 21:33:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378551AbiFGVdH (ORCPT ); Tue, 7 Jun 2022 17:33:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50076 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1381041AbiFGVbe (ORCPT ); Tue, 7 Jun 2022 17:31:34 -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 8FAF822CBCA; Tue, 7 Jun 2022 12:03:58 -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 B9A8D617CC; Tue, 7 Jun 2022 19:03:57 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BFF07C385A2; Tue, 7 Jun 2022 19:03:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1654628637; bh=TQ3Y3rgG9grSoqcDMuYepeiWXwXwF02pRKQIscNhIF0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zODXs2KpLCbt9UfK4A+R8cHAWgVDFMafSseHPfOC3kyZLUBKFhI1muoZgvGJR3v2U 3IPtj/yYsizw8tebm2lQm5S95yvtuo8duqxWxycDMViaTr4bde3ORgXHdXFFOWr2BC /z3XywpZDydLN6e2iUT4sR2eRvweGltCWvXsP8ew= 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 5.18 400/879] drm/msm/mdp5: Return error code in mdp5_mixer_release when deadlock is detected Date: Tue, 7 Jun 2022 18:58:38 +0200 Message-Id: <20220607165014.473515299@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220607165002.659942637@linuxfoundation.org> References: <20220607165002.659942637@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 ca75f6f7c6f89365e40f10f641b15981b1f07c31 ] There is a possibility for mdp5_get_global_state to return -EDEADLK when acquiring the modeset lock, but currently global_state in mdp5_mixer_release doesn't check for if an error is returned. To avoid a NULL dereference error, let's have mdp5_mixer_release check if an error is returned and propagate that error. 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/485181/ Link: https://lore.kernel.org/r/20220505214051.155-2-quic_jesszhan@quicinc.com Signed-off-by: Dmitry Baryshkov Signed-off-by: Sasha Levin --- drivers/gpu/drm/msm/disp/mdp5/mdp5_crtc.c | 10 ++++++++-- drivers/gpu/drm/msm/disp/mdp5/mdp5_mixer.c | 15 +++++++++++---- drivers/gpu/drm/msm/disp/mdp5/mdp5_mixer.h | 4 ++-- 3 files changed, 21 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_crtc.c b/drivers/gpu/drm/msm/disp/mdp5/mdp5_crtc.c index b966cd69f99d..fe2922c8d21b 100644 --- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_crtc.c +++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_crtc.c @@ -612,9 +612,15 @@ static int mdp5_crtc_setup_pipeline(struct drm_crtc *crtc, if (ret) return ret; - mdp5_mixer_release(new_crtc_state->state, old_mixer); + ret = mdp5_mixer_release(new_crtc_state->state, old_mixer); + if (ret) + return ret; + if (old_r_mixer) { - mdp5_mixer_release(new_crtc_state->state, old_r_mixer); + ret = mdp5_mixer_release(new_crtc_state->state, old_r_mixer); + if (ret) + return ret; + if (!need_right_mixer) pipeline->r_mixer = NULL; } diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_mixer.c b/drivers/gpu/drm/msm/disp/mdp5/mdp5_mixer.c index 954db683ae44..2536def2a000 100644 --- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_mixer.c +++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_mixer.c @@ -116,21 +116,28 @@ int mdp5_mixer_assign(struct drm_atomic_state *s, struct drm_crtc *crtc, return 0; } -void mdp5_mixer_release(struct drm_atomic_state *s, struct mdp5_hw_mixer *mixer) +int mdp5_mixer_release(struct drm_atomic_state *s, struct mdp5_hw_mixer *mixer) { struct mdp5_global_state *global_state = mdp5_get_global_state(s); - struct mdp5_hw_mixer_state *new_state = &global_state->hwmixer; + struct mdp5_hw_mixer_state *new_state; if (!mixer) - return; + return 0; + + if (IS_ERR(global_state)) + return PTR_ERR(global_state); + + new_state = &global_state->hwmixer; if (WARN_ON(!new_state->hwmixer_to_crtc[mixer->idx])) - return; + return -EINVAL; DBG("%s: release from crtc %s", mixer->name, new_state->hwmixer_to_crtc[mixer->idx]->name); new_state->hwmixer_to_crtc[mixer->idx] = NULL; + + return 0; } void mdp5_mixer_destroy(struct mdp5_hw_mixer *mixer) diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_mixer.h b/drivers/gpu/drm/msm/disp/mdp5/mdp5_mixer.h index 43c9ba43ce18..545ee223b9d7 100644 --- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_mixer.h +++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_mixer.h @@ -30,7 +30,7 @@ void mdp5_mixer_destroy(struct mdp5_hw_mixer *lm); int mdp5_mixer_assign(struct drm_atomic_state *s, struct drm_crtc *crtc, uint32_t caps, struct mdp5_hw_mixer **mixer, struct mdp5_hw_mixer **r_mixer); -void mdp5_mixer_release(struct drm_atomic_state *s, - struct mdp5_hw_mixer *mixer); +int mdp5_mixer_release(struct drm_atomic_state *s, + struct mdp5_hw_mixer *mixer); #endif /* __MDP5_LM_H__ */ -- 2.35.1