From nobody Fri Dec 19 03:42:06 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5508FC77B61 for ; Thu, 13 Apr 2023 22:38:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229596AbjDMWio (ORCPT ); Thu, 13 Apr 2023 18:38:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54868 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229893AbjDMWij (ORCPT ); Thu, 13 Apr 2023 18:38:39 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 28D834488 for ; Thu, 13 Apr 2023 15:38:38 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id B583064220 for ; Thu, 13 Apr 2023 22:38:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 63885C433A0; Thu, 13 Apr 2023 22:38:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1681425517; bh=vbdX/dqmOVMZruNpFyND398jkZY5rXuYcUVR0aNvnBw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qssvJRf3K0pi3IuIBrMMpDzmw12YfJrKrGRAhNS5fEnV5xcLGOJpgWpu1mm+z4JBa nLcAMKWksxGJgqIM4JX6/ysp5DQiEUZtwjWGVhWnyfiEDG/wchVW6QXcdI+R+5/mYH yHYU5YMJjF8ASWdeVkNCEaqBsoCCMjP7LVqOS00k1zO80+5hXKjBRYZFDHaalUoVO/ LcFz/CL4ErwL9HsuJutzVYiEqP6XEoTX29tA+Lyz2z0c3AtLLINfOQQIDKJYjSk2Na /2M/Uy9XS2avnRCte4sAX0sbsKyVJ6lIDyjzGh6ermTSk6SGadFjGclQLCbfBR8NOK 4/m6pL95N4g0Q== From: Stephen Boyd To: Greg Kroah-Hartman Cc: Jishnu Prakash , linux-kernel@vger.kernel.org, patches@lists.linux.dev Subject: [PATCH 6/6] spmi: Add a check for remove callback when removing a SPMI driver Date: Thu, 13 Apr 2023 15:38:34 -0700 Message-ID: <20230413223834.4084793-7-sboyd@kernel.org> X-Mailer: git-send-email 2.40.0.634.g4ca3ef3211-goog In-Reply-To: <20230413223834.4084793-1-sboyd@kernel.org> References: <20230413223834.4084793-1-sboyd@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Jishnu Prakash When removing a SPMI driver, there can be a crash due to NULL pointer dereference if it does not have a remove callback defined. This is one such call trace observed when removing the QCOM SPMI PMIC driver: dump_backtrace.cfi_jt+0x0/0x8 dump_stack_lvl+0xd8/0x16c panic+0x188/0x498 __cfi_slowpath+0x0/0x214 __cfi_slowpath+0x1dc/0x214 spmi_drv_remove+0x16c/0x1e0 device_release_driver_internal+0x468/0x79c driver_detach+0x11c/0x1a0 bus_remove_driver+0xc4/0x124 driver_unregister+0x58/0x84 cleanup_module+0x1c/0xc24 [qcom_spmi_pmic] __do_sys_delete_module+0x3ec/0x53c __arm64_sys_delete_module+0x18/0x28 el0_svc_common+0xdc/0x294 el0_svc+0x38/0x9c el0_sync_handler+0x8c/0xf0 el0_sync+0x1b4/0x1c0 If a driver has all its resources allocated through devm_() APIs and does not need any other explicit cleanup, it would not require a remove callback to be defined. Hence, add a check for remove callback presence before calling it when removing a SPMI driver. Signed-off-by: Jishnu Prakash Link: https://lore.kernel.org/r/1671601032-18397-2-git-send-email-quic_jpra= kash@quicinc.com Fixes: 6f00f8c8635f ("mfd: qcom-spmi-pmic: Use devm_of_platform_populate()") Fixes: 5a86bf343976 ("spmi: Linux driver framework for SPMI") Signed-off-by: Stephen Boyd --- drivers/spmi/spmi.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/spmi/spmi.c b/drivers/spmi/spmi.c index 5705151013b3..7313d4c18a04 100644 --- a/drivers/spmi/spmi.c +++ b/drivers/spmi/spmi.c @@ -350,7 +350,8 @@ static void spmi_drv_remove(struct device *dev) const struct spmi_driver *sdrv =3D to_spmi_driver(dev->driver); =20 pm_runtime_get_sync(dev); - sdrv->remove(to_spmi_device(dev)); + if (sdrv->remove) + sdrv->remove(to_spmi_device(dev)); pm_runtime_put_noidle(dev); =20 pm_runtime_disable(dev); --=20 https://git.kernel.org/pub/scm/linux/kernel/git/clk/linux.git/ https://git.kernel.org/pub/scm/linux/kernel/git/sboyd/spmi.git