From patchwork Thu Oct 13 06:44:59 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= X-Patchwork-Id: 13005688 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 5B560C433FE for ; Thu, 13 Oct 2022 06:53:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229460AbiJMGxw (ORCPT ); Thu, 13 Oct 2022 02:53:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57466 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229572AbiJMGxv (ORCPT ); Thu, 13 Oct 2022 02:53:51 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 113B9326D5 for ; Wed, 12 Oct 2022 23:53:50 -0700 (PDT) Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1ois5w-0002d0-KZ; Thu, 13 Oct 2022 08:53:28 +0200 Received: from [2a0a:edc0:0:900:1d::77] (helo=ptz.office.stw.pengutronix.de) by drehscheibe.grey.stw.pengutronix.de with esmtp (Exim 4.94.2) (envelope-from ) id 1ois5v-001EpY-KH; Thu, 13 Oct 2022 08:53:27 +0200 Received: from ukl by ptz.office.stw.pengutronix.de with local (Exim 4.94.2) (envelope-from ) id 1ois5u-007cJP-Tk; Thu, 13 Oct 2022 08:53:26 +0200 From: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= To: "Rafael J. Wysocki" Cc: Len Brown , James Morse , Tony Luck , Borislav Petkov , linux-acpi@vger.kernel.org, kernel@pengutronix.de Subject: [PATCH 2/2] ACPI: APEI: Warn loudly on unsuccessful driver unbind Date: Thu, 13 Oct 2022 08:44:59 +0200 Message-Id: <20221013064459.121933-2-u.kleine-koenig@pengutronix.de> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20221013064459.121933-1-u.kleine-koenig@pengutronix.de> References: <20221013064459.121933-1-u.kleine-koenig@pengutronix.de> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1957; i=u.kleine-koenig@pengutronix.de; h=from:subject; bh=atVJuSjcVnfDbW/uDQEir6CC+1Y9UD9A/dVOx9diJ1g=; b=owEBbQGS/pANAwAKAcH8FHityuwJAcsmYgBjR7PnEiDIp11f+0Nawz4yaY1JubYJGw1j8T2wSvuW mw/12JKJATMEAAEKAB0WIQR+cioWkBis/z50pAvB/BR4rcrsCQUCY0ez5wAKCRDB/BR4rcrsCTEYB/ 4piJmq5j181mzKeFR1rGU60K2imMQhByOddMzR7SQMGfknFMjHXAqy+mVZX9tKCtuFx4ugXDhwb+OR yyFr1EPjfcADt5/DLNNmkLiSivVL687bWJUF0MFUEICcBYR3epMA37CPaYTpEnwXGmruHzs3pcIuQy oM3uFDj0QTm6ydwt806v6G0ufVN5pPXak4Jr8z52yV5urlRtTGdAovCtorVMa1NnNCRh3CmhUyb8I/ qlzVSJN6ZNzaPB2wX/MocUJKw2IIuNCUu5Ljil2Ov6ib6N4oH1k3omLcRmys3kDE7p//bsGkKFh+nA aAFCcSv4KpLd+/wOZthlO5YRn/oeBa X-Developer-Key: i=u.kleine-koenig@pengutronix.de; a=openpgp; fpr=0D2511F322BFAB1C1580266BE2DCDD9132669BD6 X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-acpi@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org If the remove callback failed, it leaves some unfreed resources behind that will never be cleared. I didn't manage to understand the driver good enough to judge how critical that really is. This patch is part of an effort to change the remove callbacks for platform devices to return void in the hope this will prevent the wrong assumption that returning an error code from .remove() is proper error handling. Signed-off-by: Uwe Kleine-König --- drivers/acpi/apei/ghes.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) Hello, on a side note: The remove callback calls (in some cases) free_irq() for a shared interrupt. A requirement in this case is to disable the device's interrupt beforehand. It's not obvious (to me that is) that said irq is disabled here. This is another opportunity for ugly things to happen. Best regards Uwe diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index 307fbb97a116..78d2e4df74ee 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -1393,7 +1393,7 @@ static int ghes_probe(struct platform_device *ghes_dev) return rc; } -static int ghes_remove(struct platform_device *ghes_dev) +static int _ghes_remove(struct platform_device *ghes_dev) { int rc; struct ghes *ghes; @@ -1447,6 +1447,21 @@ static int ghes_remove(struct platform_device *ghes_dev) return 0; } +static int ghes_remove(struct platform_device *ghes_dev) +{ + /* + * If _ghes_remove() returns an error, we're in trouble. Some of the + * cleanup was skipped then and this will never be catched up. So some + * resources will stay around, maybe even used although the platform + * device will be gone. + */ + int err = _ghes_remove(ghes_dev); + + WARN_ON(err); + + return 0; +} + static struct platform_driver ghes_platform_driver = { .driver = { .name = "GHES",