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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 B635CC3F375 for ; Thu, 27 Feb 2020 13:54:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8F74E2469D for ; Thu, 27 Feb 2020 13:54:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582811665; bh=i4rCMs/KdszCUrhFYZjd38y7vAH2KN/V466RTKcmpKo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=rUrBeTcLL6LLsJEzDq3WVGPnkmOms11L2Xdf3YQlaHy4M0b9+QElnSEq9Rnbc8Yq/ 03jkY5SVrFWh9z6/dPJ3Skm72niifbPo+T9cGblek+wDcj4Kcx0Im2J6/aw5QJkeP4 t7LD/iiUJntS2iHpuWgpfizyKS5+UrQysA0do9i0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731866AbgB0NyY (ORCPT ); Thu, 27 Feb 2020 08:54:24 -0500 Received: from mail.kernel.org ([198.145.29.99]:54404 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731857AbgB0NyU (ORCPT ); Thu, 27 Feb 2020 08:54:20 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CF3E020801; Thu, 27 Feb 2020 13:54:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582811660; bh=i4rCMs/KdszCUrhFYZjd38y7vAH2KN/V466RTKcmpKo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MMfLXDag2iwQqDYP++rZDV0hrjFfAZTggpJsvj0xVA1dC6prVTy8DF3UsfPhc6XNw wIhxBQbiagpfMmu5TMazD9Wl+m2HhetwD1HkT4EFgkIe8f1FvhOeeD1MFBQ7KK5BY0 fjRxi39Zddv1usHHDl4yQhfabV61d5H8JSJLUpdQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jia-Ju Bai , Fabien Dessenne , Hans Verkuil , Mauro Carvalho Chehab , Sasha Levin Subject: [PATCH 4.14 052/237] media: sti: bdisp: fix a possible sleep-in-atomic-context bug in bdisp_device_run() Date: Thu, 27 Feb 2020 14:34:26 +0100 Message-Id: <20200227132300.611923225@linuxfoundation.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200227132255.285644406@linuxfoundation.org> References: <20200227132255.285644406@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jia-Ju Bai [ Upstream commit bb6d42061a05d71dd73f620582d9e09c8fbf7f5b ] The driver may sleep while holding a spinlock. The function call path (from bottom to top) in Linux 4.19 is: drivers/media/platform/sti/bdisp/bdisp-hw.c, 385: msleep in bdisp_hw_reset drivers/media/platform/sti/bdisp/bdisp-v4l2.c, 341: bdisp_hw_reset in bdisp_device_run drivers/media/platform/sti/bdisp/bdisp-v4l2.c, 317: _raw_spin_lock_irqsave in bdisp_device_run To fix this bug, msleep() is replaced with udelay(). This bug is found by a static analysis tool STCheck written by myself. Signed-off-by: Jia-Ju Bai Reviewed-by: Fabien Dessenne Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- drivers/media/platform/sti/bdisp/bdisp-hw.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/media/platform/sti/bdisp/bdisp-hw.c b/drivers/media/platform/sti/bdisp/bdisp-hw.c index b7892f3efd988..5c4c3f0c57be1 100644 --- a/drivers/media/platform/sti/bdisp/bdisp-hw.c +++ b/drivers/media/platform/sti/bdisp/bdisp-hw.c @@ -14,8 +14,8 @@ #define MAX_SRC_WIDTH 2048 /* Reset & boot poll config */ -#define POLL_RST_MAX 50 -#define POLL_RST_DELAY_MS 20 +#define POLL_RST_MAX 500 +#define POLL_RST_DELAY_MS 2 enum bdisp_target_plan { BDISP_RGB, @@ -382,7 +382,7 @@ int bdisp_hw_reset(struct bdisp_dev *bdisp) for (i = 0; i < POLL_RST_MAX; i++) { if (readl(bdisp->regs + BLT_STA1) & BLT_STA1_IDLE) break; - msleep(POLL_RST_DELAY_MS); + udelay(POLL_RST_DELAY_MS * 1000); } if (i == POLL_RST_MAX) dev_err(bdisp->dev, "Reset timeout\n"); -- 2.20.1