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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 0B16BC33CA3 for ; Thu, 9 Jan 2020 13:35:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E13F720838 for ; Thu, 9 Jan 2020 13:35:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731108AbgAINfY (ORCPT ); Thu, 9 Jan 2020 08:35:24 -0500 Received: from mail-qk1-f194.google.com ([209.85.222.194]:32975 "EHLO mail-qk1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728974AbgAINfY (ORCPT ); Thu, 9 Jan 2020 08:35:24 -0500 Received: by mail-qk1-f194.google.com with SMTP id d71so5980868qkc.0; Thu, 09 Jan 2020 05:35:23 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=vK5UxuBrViNaXxuMZEsGhiSGSEMvZsYzv98RipTZfGg=; b=s1UNeLX8809o92ijYT5HikWwRFLcu3yDQDRjnyKAI3ebjg2fw+tfkA63SKrKZ4oBFL NIAGPKWgDpMm/V/drl8ia7BooYxzmGsh0P61Ngn5+cI33GRhHTq7p3YNe1O7rqu06t8I BrTAjNLP/CXJoN79JWAh9ZFmZl9UzyAMP1oqYg4Zinish8Dj+TawkkuwJqxsF9tshQKy qJTwa8sTmtqNz5RiNLSl/sP+yIfrjDtvlqCS+cPwZxBtnUXL1Kj73Hm01HAsUpGB6LRj G6tnHxD7Qn6GOVF2BezCUyTbQrH0u5QggPci7aK+P3AWfkY7S2UKNkasHuMiXyHI/6B+ CwcA== X-Gm-Message-State: APjAAAVS5wq1mKhWdJbXO+NZrAucozVXb5UecaIWxEAiAwEq8xnGIt1n dHA/FkrW/xvc5RsM7mc28c+qhG6e1MqbfRvD8KQ= X-Google-Smtp-Source: APXvYqyRXgYk8j5kdfM4/WS8TEs831mjz2YcxqkRufdK/tyDKS85bDKPS8c3TecGMtuEwZvySvABfGqCivPuJ6qeC0Q= X-Received: by 2002:a05:620a:134f:: with SMTP id c15mr9195003qkl.115.1578576923178; Thu, 09 Jan 2020 05:35:23 -0800 (PST) MIME-Version: 1.0 References: <20191127084253.16356-1-geert+renesas@glider.be> <20191127084253.16356-6-geert+renesas@glider.be> <20191203105103.GA20470@x230> In-Reply-To: <20191203105103.GA20470@x230> From: Geert Uytterhoeven Date: Thu, 9 Jan 2020 14:35:10 +0100 Message-ID: Subject: Re: [PATCH v3 5/7] gpio: Add GPIO Aggregator/Repeater driver To: Eugeniu Rosca Cc: Geert Uytterhoeven , Linus Walleij , Bartosz Golaszewski , Jonathan Corbet , Rob Herring , Mark Rutland , Harish Jenny K N , Eugeniu Rosca , Alexander Graf , Peter Maydell , Paolo Bonzini , Phil Reid , Marc Zyngier , Christoffer Dall , Magnus Damm , "open list:GPIO SUBSYSTEM" , "open list:DOCUMENTATION" , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , Linux-Renesas , Linux Kernel Mailing List , QEMU Developers Content-Type: text/plain; charset="UTF-8" Sender: linux-renesas-soc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-renesas-soc@vger.kernel.org Hi Eugeniu, On Tue, Dec 3, 2019 at 11:51 AM Eugeniu Rosca wrote: > On Wed, Nov 27, 2019 at 09:42:51AM +0100, Geert Uytterhoeven wrote: > > +static int gpio_aggregator_probe(struct platform_device *pdev) > > +{ > > + struct device *dev = &pdev->dev; > > + struct gpio_desc **descs; > > + struct gpiochip_fwd *fwd; > > + int i, n; > > FWIW/FTR, doing some blind creation and deletion of gpio aggregator > chips [1] on R-Car H3ULCB overnight, kmemleak reported once [2]. Not > sure this is something 100% reproducible. > > [1] while true; do \ > echo e6055400.gpio 12,13 > /sys/bus/platform/drivers/gpio-aggregator/new_device; \ > echo gpio-aggregator.0 > /sys/bus/platform/drivers/gpio-aggregator/delete_device; \ > done > > [2] unreferenced object 0xffff0006d2c2e000 (size 128): > comm "kworker/3:1", pid 55, jiffies 4294676978 (age 38546.676s) > hex dump (first 32 bytes): > 00 d9 d2 d3 06 00 ff ff 0c 00 e0 0f ff ff ff ff ................ > 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > backtrace: > [<00000000a8e18c13>] slab_post_alloc_hook+0x8c/0x94 > [<000000006f419a4f>] __kmalloc+0x170/0x218 > [<0000000060d185ea>] kobj_map+0x78/0x1c0 > [<00000000c96645f3>] cdev_add+0x68/0x94 > [<00000000a7a5a8ac>] cdev_device_add+0x74/0x90 > [<00000000497871d3>] gpiochip_setup_dev+0x84/0x1f0 > [<00000000b993f95f>] gpiochip_add_data_with_key+0xbcc/0x11f0 > [<00000000fd728c0e>] devm_gpiochip_add_data+0x60/0xa8 > [<00000000442e34c1>] gpio_aggregator_probe+0x210/0x3c8 > [<00000000076e13fb>] platform_drv_probe+0x70/0xe4 > [<00000000de84b58b>] really_probe+0x2d8/0x434 > [<00000000c95c9784>] driver_probe_device+0x15c/0x16c > [<00000000afb7dd4f>] __device_attach_driver+0xdc/0x120 > [<00000000efa40cae>] bus_for_each_drv+0x12c/0x154 > [<00000000c149acef>] __device_attach+0x148/0x1e0 > [<00000000a74fd158>] device_initial_probe+0x24/0x30 This is the allocation of the GPIO character device, which is allocated in response to the creation of the GPIO chip, from .probe(). As that is done using devm_gpiochip_add_data(), the chardev should be deallocated automatically by devm_gpio_chip_release() when platform_device_unregister() is called. Weird... Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds