From patchwork Thu Oct 20 14:39:52 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Takashi Iwai X-Patchwork-Id: 9386975 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id BA9E660487 for ; Thu, 20 Oct 2016 14:40:05 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id AC81329CA8 for ; Thu, 20 Oct 2016 14:40:05 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A0D2629CB0; Thu, 20 Oct 2016 14:40:05 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 95AE429CA8 for ; Thu, 20 Oct 2016 14:40:04 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 40B0B6E03F; Thu, 20 Oct 2016 14:39:58 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by gabe.freedesktop.org (Postfix) with ESMTPS id D13E46E03F for ; Thu, 20 Oct 2016 14:39:56 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id C3EE0ADAF; Thu, 20 Oct 2016 14:39:54 +0000 (UTC) From: Takashi Iwai To: dri-devel@lists.freedesktop.org Subject: [PATCH] drm/fb-helper: Don't call dirty callback for untouched clips Date: Thu, 20 Oct 2016 16:39:52 +0200 Message-Id: <20161020143952.2538-1-tiwai@suse.de> X-Mailer: git-send-email 2.10.1 Cc: linux-kernel@vger.kernel.org X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP Since 4.7 kernel, we've seen the error messages like kernel: [TTM] Buffer eviction failed kernel: qxl 0000:00:02.0: object_init failed for (4026540032, 0x00000001) kernel: [drm:qxl_alloc_bo_reserved [qxl]] *ERROR* failed to allocate VRAM BO on QXL when switching and accessing on VT. The culprit was the generic deferred_io code (qxl driver switched to it since 4.7). There is a race between the dirty clip update and the call of callback. In drm_fb_helper_dirty(), the dirty clip is updated in the spinlock, while it kicks off the update worker outside the spinlock. Meanwhile the update worker clears the dirty clip in the spinlock, too. Thus, when drm_fb_helper_dirty() is called concurrently, schedule_work() is called after the clip is cleared in the first worker call. This patch addresses it by validating the clip before calling the dirty fb callback. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98322 Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=1003298 Fixes: eaa434defaca ('drm/fb-helper: Add fb_deferred_io support') Cc: Signed-off-by: Takashi Iwai --- drivers/gpu/drm/drm_fb_helper.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 03414bde1f15..d790d205129e 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -636,15 +636,20 @@ static void drm_fb_helper_dirty_work(struct work_struct *work) dirty_work); struct drm_clip_rect *clip = &helper->dirty_clip; struct drm_clip_rect clip_copy; + bool dirty; unsigned long flags; spin_lock_irqsave(&helper->dirty_lock, flags); - clip_copy = *clip; - clip->x1 = clip->y1 = ~0; - clip->x2 = clip->y2 = 0; + dirty = (clip->x1 < clip->x2 && clip->y1 < clip->y2); + if (dirty) { + clip_copy = *clip; + clip->x1 = clip->y1 = ~0; + clip->x2 = clip->y2 = 0; + } spin_unlock_irqrestore(&helper->dirty_lock, flags); - helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, &clip_copy, 1); + if (dirty) + helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, &clip_copy, 1); } /**