From patchwork Wed Aug 19 10:30:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tomi Valkeinen X-Patchwork-Id: 11723455 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 005DC618 for ; Wed, 19 Aug 2020 10:31:33 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id D14BB2076E for ; Wed, 19 Aug 2020 10:31:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=ti.com header.i=@ti.com header.b="xKI/bKRI" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D14BB2076E Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=ti.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D6A0A89295; Wed, 19 Aug 2020 10:31:29 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from lelv0143.ext.ti.com (lelv0143.ext.ti.com [198.47.23.248]) by gabe.freedesktop.org (Postfix) with ESMTPS id 816A389295 for ; Wed, 19 Aug 2020 10:31:28 +0000 (UTC) Received: from lelv0266.itg.ti.com ([10.180.67.225]) by lelv0143.ext.ti.com (8.15.2/8.15.2) with ESMTP id 07JAVOPh020940; Wed, 19 Aug 2020 05:31:24 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1597833084; bh=1ileKBQlCD86SCsvKLgEXbnRapYDozHuzrHtk0yUBqs=; h=From:To:CC:Subject:Date; b=xKI/bKRI/zn7hfJ1dnHNE+KhU8CCnQmGT5w25Q/UUB/rQaJDvv5qZhsbkor8OkGPs U723RbdCkteDBG/1AvgAQGbwp0QoWweBM66rt8GOgQKG89t4i1DV6C4Ei4TpTE1N5J Oi/r8HTbYJ7GAr3YBsQmy6Ave1n4TTJXfg308DYU= Received: from DLEE102.ent.ti.com (dlee102.ent.ti.com [157.170.170.32]) by lelv0266.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 07JAVOxg011436 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 19 Aug 2020 05:31:24 -0500 Received: from DLEE108.ent.ti.com (157.170.170.38) by DLEE102.ent.ti.com (157.170.170.32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3; Wed, 19 Aug 2020 05:30:31 -0500 Received: from lelv0327.itg.ti.com (10.180.67.183) by DLEE108.ent.ti.com (157.170.170.38) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3 via Frontend Transport; Wed, 19 Aug 2020 05:30:31 -0500 Received: from deskari.lan (ileax41-snat.itg.ti.com [10.172.224.153]) by lelv0327.itg.ti.com (8.15.2/8.15.2) with ESMTP id 07JAUTTF089812; Wed, 19 Aug 2020 05:30:30 -0500 From: Tomi Valkeinen To: , Laurent Pinchart Subject: [PATCH] drm/omap: fix incorrect lock state Date: Wed, 19 Aug 2020 13:30:21 +0300 Message-ID: <20200819103021.440288-1-tomi.valkeinen@ti.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Tomi Valkeinen Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" After commit 92cc68e35863c1c61c449efa2b2daef6e9926048 ("drm/vblank: Use spin_(un)lock_irq() in drm_crtc_vblank_on()") omapdrm locking is broken: WARNING: inconsistent lock state 5.8.0-rc2-00483-g92cc68e35863 #13 Tainted: G W -------------------------------- inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage. swapper/0/0 [HC1[1]:SC0[0]:HE0:SE1] takes: ea98222c (&dev->event_lock#2){?.+.}-{2:2}, at: drm_handle_vblank+0x4c/0x520 [drm] {HARDIRQ-ON-W} state was registered at: trace_hardirqs_on+0x9c/0x1ec _raw_spin_unlock_irq+0x20/0x58 omap_crtc_atomic_enable+0x54/0xa0 [omapdrm] drm_atomic_helper_commit_modeset_enables+0x218/0x270 [drm_kms_helper] omap_atomic_commit_tail+0x48/0xc4 [omapdrm] commit_tail+0x9c/0x190 [drm_kms_helper] drm_atomic_helper_commit+0x154/0x188 [drm_kms_helper] drm_client_modeset_commit_atomic+0x228/0x268 [drm] drm_client_modeset_commit_locked+0x60/0x1d0 [drm] drm_client_modeset_commit+0x24/0x40 [drm] drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa8 [drm_kms_helper] drm_fb_helper_set_par+0x2c/0x5c [drm_kms_helper] drm_fb_helper_hotplug_event.part.0+0xa0/0xbc [drm_kms_helper] drm_kms_helper_hotplug_event+0x24/0x30 [drm_kms_helper] output_poll_execute+0x1a8/0x1c0 [drm_kms_helper] process_one_work+0x268/0x800 worker_thread+0x30/0x4e0 kthread+0x164/0x190 ret_from_fork+0x14/0x20 The reason for this is that omapdrm calls drm_crtc_vblank_on() while holding event_lock taken with spin_lock_irq(). It is not clear why drm_crtc_vblank_on() and drm_crtc_vblank_get() are called while holding event_lock. I don't see any problem with moving those calls outside the lock, which is what this patch does. Signed-off-by: Tomi Valkeinen Reviewed-by: Laurent Pinchart --- drivers/gpu/drm/omapdrm/omap_crtc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/omapdrm/omap_crtc.c b/drivers/gpu/drm/omapdrm/omap_crtc.c index 6d40914675da..328a4a74f534 100644 --- a/drivers/gpu/drm/omapdrm/omap_crtc.c +++ b/drivers/gpu/drm/omapdrm/omap_crtc.c @@ -451,11 +451,12 @@ static void omap_crtc_atomic_enable(struct drm_crtc *crtc, if (omap_state->manually_updated) return; - spin_lock_irq(&crtc->dev->event_lock); drm_crtc_vblank_on(crtc); + ret = drm_crtc_vblank_get(crtc); WARN_ON(ret != 0); + spin_lock_irq(&crtc->dev->event_lock); omap_crtc_arm_event(crtc); spin_unlock_irq(&crtc->dev->event_lock); }