From patchwork Fri Nov 17 09:16:58 2023 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: 13458568 X-Patchwork-Delegate: kuba@kernel.org Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: from metis.whiteo.stw.pengutronix.de (metis.whiteo.stw.pengutronix.de [IPv6:2a0a:edc0:2:b01:1d::104]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D4969D51 for ; Fri, 17 Nov 2023 01:17:27 -0800 (PST) Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1r3uyP-0007gP-QB; Fri, 17 Nov 2023 10:17:13 +0100 Received: from [2a0a:edc0:0:900:1d::77] (helo=ptz.office.stw.pengutronix.de) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1r3uyP-009e6A-CX; Fri, 17 Nov 2023 10:17:13 +0100 Received: from ukl by ptz.office.stw.pengutronix.de with local (Exim 4.94.2) (envelope-from ) id 1r3uyP-002yJb-3L; Fri, 17 Nov 2023 10:17:13 +0100 From: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= To: Cc: Siddharth Vadapalli , Ravi Gunasekaran , Roger Quadros , Simon Horman , Yunsheng Lin , Stanislav Fomichev , Marek Majtyka , Rob Herring , Mugunthan V N , linux-omap@vger.kernel.org, netdev@vger.kernel.org, kernel@pengutronix.de Subject: [PATCH 2/7] net: ethernet: ti: cpsw: Don't error out in .remove() Date: Fri, 17 Nov 2023 10:16:58 +0100 Message-ID: <20231117091655.872426-3-u.kleine-koenig@pengutronix.de> X-Mailer: git-send-email 2.42.0.586.gbc5204569f7d.dirty In-Reply-To: <20231117091655.872426-1-u.kleine-koenig@pengutronix.de> References: <20231117091655.872426-1-u.kleine-koenig@pengutronix.de> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1891; i=u.kleine-koenig@pengutronix.de; h=from:subject; bh=mRlxVGBjOW+sHBqJcFFxN2V+8op/8Ztc44BTgG2kkTc=; b=owEBbQGS/pANAwAKAY+A+1h9Ev5OAcsmYgBlVy+JX7JX54FLhK+Ph4PRFjYhrozP75HV5r1Hh eI54zRdHrCJATMEAAEKAB0WIQQ/gaxpOnoeWYmt/tOPgPtYfRL+TgUCZVcviQAKCRCPgPtYfRL+ TukvCAClEeHXl2S3JJqY2Bxwz4qdVHZrIaNBphbJm/tByatOnJypsqbGilBmtS8u4DOJ+9JdsST /40Lod7dQZ432LRW1PomY92egZ5iSekSFW+KE12uA1lhufDdNlc/fZNoHbnaa7t3v6cpV2n1OUc T1Qe5rWHW1XM5Ak6pT7CsxFKqZKX8mZykXfcqriVvKO8hgJjTLkybTWZQwMccbuPDy5oNYxK0Da ipSgmSTQ225CTGdMswUGhsAZjspi9R0T22vUikLBqY/vyxx6+fzrc+wV6xBfGYEETdRVNWJMQJo jgwiZUGJGJl6mMSy4Sh8UJAcq7Z04ffRmlWOK5XeEGrrK5ex 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.whiteo.stw.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Returning early from .remove() with an error code still results in the driver unbinding the device. So the driver core ignores the returned error code and the resources that were not freed are never catched up. In combination with devm this also often results in use-after-free bugs. If runtime resume fails, it's still important to free all resources, so don't return with an error code, but emit an error message and continue freeing acquired stuff. This prepares changing cpsw_remove() to return void. Fixes: 8a0b6dc958fd ("drivers: net: cpsw: fix wrong regs access in cpsw_remove") Signed-off-by: Uwe Kleine-König --- drivers/net/ethernet/ti/cpsw.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c index ca4d4548f85e..db5a2ba8a6d4 100644 --- a/drivers/net/ethernet/ti/cpsw.c +++ b/drivers/net/ethernet/ti/cpsw.c @@ -1727,16 +1727,24 @@ static int cpsw_remove(struct platform_device *pdev) struct cpsw_common *cpsw = platform_get_drvdata(pdev); int i, ret; - ret = pm_runtime_resume_and_get(&pdev->dev); + ret = pm_runtime_get_sync(&pdev->dev); if (ret < 0) - return ret; + /* There is no need to do something about that. The important + * thing is to not exit early, but do all cleanup that doesn't + * require register access. + */ + dev_err(&pdev->dev, "runtime resume failed (%pe)\n", + ERR_PTR(ret)); for (i = 0; i < cpsw->data.slaves; i++) if (cpsw->slaves[i].ndev) unregister_netdev(cpsw->slaves[i].ndev); - cpts_release(cpsw->cpts); - cpdma_ctlr_destroy(cpsw->dma); + if (ret >= 0) { + cpts_release(cpsw->cpts); + cpdma_ctlr_destroy(cpsw->dma); + } + cpsw_remove_dt(pdev); pm_runtime_put_sync(&pdev->dev); pm_runtime_disable(&pdev->dev);