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 X-Spam-Level: X-Spam-Status: No, score=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EE299C33CBB for ; Mon, 10 May 2021 11:41:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B02F5611C2 for ; Mon, 10 May 2021 11:41:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242294AbhEJLlo (ORCPT ); Mon, 10 May 2021 07:41:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:52778 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231621AbhEJK5i (ORCPT ); Mon, 10 May 2021 06:57:38 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8AB1261979; Mon, 10 May 2021 10:51:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620643913; bh=vhNdZITQLLu1Vqwt/HaWW/3rsi9z4orMusNDvuWFim8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SriucXP5ESDihLwYDZwkn+3h++Npr30gddwJTjBZaFevAmPL6KUBIr81MjJOyDGqW mFm3QdMs1zOlB6T3fIesHKzYOMQPxxOFI8JsJ064Pkg1bs+Dc12PgDgsbzmJdommEb DYcfWLYEsNLTPEMaJ6FJ6Ed9Fo/JEbED5ALy2IG8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dmitry Vyukov , syzbot+4fc21a003c8332eb0bdd@syzkaller.appspotmail.com, Rodrigo Siqueira , Melissa Wen , Haneen Mohammed , Daniel Vetter , David Airlie , dri-devel@lists.freedesktop.org, Sasha Levin Subject: [PATCH 5.11 176/342] drm/vkms: fix misuse of WARN_ON Date: Mon, 10 May 2021 12:19:26 +0200 Message-Id: <20210510102015.920642905@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210510102010.096403571@linuxfoundation.org> References: <20210510102010.096403571@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: linux-kernel@vger.kernel.org From: Dmitry Vyukov [ Upstream commit b4142fc4d52d051d4d8df1fb6c569e5b445d369e ] vkms_vblank_simulate() uses WARN_ON for timing-dependent condition (timer overrun). This is a mis-use of WARN_ON, WARN_ON must be used to denote kernel bugs. Use pr_warn() instead. Signed-off-by: Dmitry Vyukov Reported-by: syzbot+4fc21a003c8332eb0bdd@syzkaller.appspotmail.com Cc: Rodrigo Siqueira Cc: Melissa Wen Cc: Haneen Mohammed Cc: Daniel Vetter Cc: David Airlie Cc: dri-devel@lists.freedesktop.org Cc: linux-kernel@vger.kernel.org Acked-by: Melissa Wen Signed-off-by: Melissa Wen Link: https://patchwork.freedesktop.org/patch/msgid/20210320132840.1315853-1-dvyukov@google.com Signed-off-by: Sasha Levin --- drivers/gpu/drm/vkms/vkms_crtc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c index 0443b7deeaef..758d8a98d96b 100644 --- a/drivers/gpu/drm/vkms/vkms_crtc.c +++ b/drivers/gpu/drm/vkms/vkms_crtc.c @@ -18,7 +18,8 @@ static enum hrtimer_restart vkms_vblank_simulate(struct hrtimer *timer) ret_overrun = hrtimer_forward_now(&output->vblank_hrtimer, output->period_ns); - WARN_ON(ret_overrun != 1); + if (ret_overrun != 1) + pr_warn("%s: vblank timer overrun\n", __func__); spin_lock(&output->lock); ret = drm_crtc_handle_vblank(crtc); -- 2.30.2