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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 3381AC433DF for ; Thu, 2 Jul 2020 01:32:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 001FA206BE for ; Thu, 2 Jul 2020 01:32:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593653544; bh=0PE/ZEegeyQ50KVBzDMMsCfxPGXZ/ksQVk9m47noOKU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=RVsdUu+Reh0c1y8xG5ExZcGqgHE3OP5gV/MsaEcjj6gBBWFcgvktTEC7OcutyewlD Z38rU3ffG0D+4UAE2Qe/bF4RkCz6aiJQlgFXIx9wcknJrMvk85YpamD6JKmSFt3DHq fEmXL6tY1VVDZb3mYcdJDtzERgXb0zwLc+SDqnNE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729053AbgGBBcW (ORCPT ); Wed, 1 Jul 2020 21:32:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:57624 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729147AbgGBB0V (ORCPT ); Wed, 1 Jul 2020 21:26:21 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0345D206BE; Thu, 2 Jul 2020 01:26:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593653180; bh=0PE/ZEegeyQ50KVBzDMMsCfxPGXZ/ksQVk9m47noOKU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gCmt7OwR25sH05Id4DW8RQ7YBjM98/ZJaGMAq3yo/ALhxGyqai2DIXzlEhnotqmN5 BbHcEJQ8oLIMbP+0vQw13GqBYIXkb0VulqqFDG9aBkBvJ4A992GG3G4RdlnIhMafrh qGUsG3D4biFNQmfdNYIXE0gENZNxzzmW3ApwS++k= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Thierry Reding , Sowjanya Komatineni , Sasha Levin , dri-devel@lists.freedesktop.org, linux-tegra@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 04/27] gpu: host1x: Detach driver on unregister Date: Wed, 1 Jul 2020 21:25:52 -0400 Message-Id: <20200702012615.2701532-4-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200702012615.2701532-1-sashal@kernel.org> References: <20200702012615.2701532-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Thierry Reding [ Upstream commit d9a0a05bf8c76e6dc79230669a8b5d685b168c30 ] Currently when a host1x device driver is unregistered, it is not detached from the host1x controller, which means that the device will stay around and when the driver is registered again, it may bind to the old, stale device rather than the new one that was created from scratch upon driver registration. This in turn can cause various weird crashes within the driver core because it is confronted with a device that was already deleted. Fix this by detaching the driver from the host1x controller when it is unregistered. This ensures that the deleted device also is no longer present in the device list that drivers will bind to. Reported-by: Sowjanya Komatineni Signed-off-by: Thierry Reding Tested-by: Sowjanya Komatineni Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin --- drivers/gpu/host1x/bus.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/gpu/host1x/bus.c b/drivers/gpu/host1x/bus.c index 0121fe7a4548d..02f896b50ed07 100644 --- a/drivers/gpu/host1x/bus.c +++ b/drivers/gpu/host1x/bus.c @@ -632,8 +632,17 @@ EXPORT_SYMBOL(host1x_driver_register_full); */ void host1x_driver_unregister(struct host1x_driver *driver) { + struct host1x *host1x; + driver_unregister(&driver->driver); + mutex_lock(&devices_lock); + + list_for_each_entry(host1x, &devices, list) + host1x_detach_driver(host1x, driver); + + mutex_unlock(&devices_lock); + mutex_lock(&drivers_lock); list_del_init(&driver->list); mutex_unlock(&drivers_lock); -- 2.25.1