From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ABBA7485924; Thu, 10 Sep 2026 12:19:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789042760; cv=none; b=I6jdwvAJAOgz3fcx8Vuagsz8hRod9ORuy6R0s49slzoAwxT5wfsPcK4q8qVLlykd3KWSrmxLwRhYR2jXn2285f5zJL4i/mVpXmHHOES3/purjTzlyxU9fmR1odt/CnTVBXaLDSxFJ5wJ9EpMTwZJ33MvSZNDihstL232/BKiMOM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789042760; c=relaxed/simple; bh=cDGccnCHgPHIlF54bAD1WKnZpiTUq/d7xuYiKTx1Fg4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=h8ykcySKgyvAdylG4KkakSNylo7HKGA1Ivjm+0JaUXJFZscuFgsEfMwQSPPmNfeKMKyRxqMvOVx4XmgXfNEIjnzuhBABxQMR1AgxVlyyzK6CiEltu0sZnZ7nhF8qqnNLPY/s+J+cz2lPje6simJYSZBy4zORbHhsUJBlUbdWAd8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CxjyZs0f; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="CxjyZs0f" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AB5F71F000FF; Thu, 10 Sep 2026 12:19:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789042757; bh=S75Jnd9qY6Y5N51b46uYpbSY10v2y0F3rUD8oub3+24=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=CxjyZs0fGdFv31jwlTmJO0uyFl/AO/9E7kQDoAZd1kZOf/3j2F8k33AH3/rtcVpLm UajGdEbyyRjylIi2ohYuMtBKsqapHzCY628Ts3Pvh5MJs429Df3RI8HRO15SDPgdMO MN+Tvw5GWnw06CsA2kp0y7iAwMJoZnOVwpxNG8JTgUpGTlGt8kQA//gw5cPgHlFHZ8 V6sW2ynNVoMqMCUp1jKP3gc6oFhzK7PN4X6XNrAij12+sxR5efyXX89/koeybbwcoi RkOEgXENdhRD6S62cJJ3YGwP4y6Mvx09l/wbc0ov/toXVG1E83uGkEk0M1ll9g2cDR 9F/Y8eMI9L7sg== From: Niklas Cassel To: Damien Le Moal , Niklas Cassel , Hans de Goede , Jeff Garzik , Brian Norris Cc: stable@vger.kernel.org, linux-ide@vger.kernel.org Subject: [PATCH v3 2/3] ata: libata: Do not leave ata_host_stop() registered when activation fails Date: Thu, 10 Sep 2026 14:19:02 +0200 Message-ID: <20260910121900.97676-7-cassel@kernel.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260910121900.97676-5-cassel@kernel.org> References: <20260910121900.97676-5-cassel@kernel.org> Precedence: bulk X-Mailing-List: linux-ide@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=10445; i=cassel@kernel.org; h=from:subject; bh=cDGccnCHgPHIlF54bAD1WKnZpiTUq/d7xuYiKTx1Fg4=; b=owGbwMvMwCV2MsVw8cxjvkWMp9WSGLIWLTDNdmtPdTxvfKFNcwdj34aHibNPxnAveLFg1f0VX ptevxNa0FHKwiDGxSArpsji+8Nlf3G3+5TjindsYOawMoEMYeDiFICJnPdkZFjNHqylHzy7/HpI K9ds/p2HvuYXS+7nvfRgruXGwrVx18IYGa4kX9u5NHnTI5ZJrSHlubM33ny+z8rmbochl1RoaNf bJ8wA X-Developer-Key: i=cassel@kernel.org; a=openpgp; fpr=5ADE635C0E631CBBD5BE065A352FE6582ED9B5DA Content-Transfer-Encoding: 8bit ata_host_start() registers ata_host_stop() as a devres action as soon as it has succeeded, which hands the release of the host resources over to devres: ->port_stop() and ->host_stop() are then called by the driver core when probe() fails. ata_host_activate() and ahci_host_activate_multi_irqs() can both fail after ata_host_start() has succeeded, e.g. if devm_request_irq() or ata_host_register() fails, and they return the error with the devres action still registered. A driver which releases the host resources in its probe() error path therefore releases them twice: once itself and once through ->host_stop(). All ahci-platform drivers are in that situation, e.g. ahci_probe() calls ahci_platform_disable_resources() while ahci_host_stop() does the same through devres. This gives refcount underflow warnings from the clk, regulator and phy cores and, for shared resources, can disable resources which are still in use by other devices. Add ata_host_undo_start(), which stops the ports and drops the devres action without calling ->host_stop(), and call it from both activation helpers when they fail. Releasing the host resources on failure is then always left to the caller, which is what all callers having a probe() error path already assume. This changes the semantics for the drivers which implement ->host_stop() while also completely lacking error handling for the activate host call. Add activate host error handling for sata_qstor and sata_fsl. Note that ata_pci_sff_activate_host() is deliberately left as is: none of its callers releases the host resources in its probe() error path, they all rely on ->host_stop() being called by devres, including ata_pci_init_one(), which releases the devres group of the host itself. Fixes: 1896b15eddb4 ("ahci_platform: perform platform exit in host_stop() hook") Cc: stable@vger.kernel.org Signed-off-by: Niklas Cassel --- drivers/ata/libahci.c | 17 +++++++- drivers/ata/libahci_platform.c | 4 ++ drivers/ata/libata-core.c | 75 +++++++++++++++++++++++++++++++--- drivers/ata/libata-sff.c | 5 +++ drivers/ata/sata_fsl.c | 8 +++- drivers/ata/sata_qstor.c | 8 +++- include/linux/libata.h | 1 + 7 files changed, 106 insertions(+), 12 deletions(-) diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c index 6d72eb017b49..7260adde8f7d 100644 --- a/drivers/ata/libahci.c +++ b/drivers/ata/libahci.c @@ -2723,11 +2723,20 @@ static int ahci_host_activate_multi_irqs(struct ata_host *host, 0, pp->irq_desc, host->ports[i]); if (rc) - return rc; + goto undo_start; ata_port_desc_misc(host->ports[i], irq); } - return ata_host_register(host, sht); + rc = ata_host_register(host, sht); + if (rc) + goto undo_start; + + return 0; + +undo_start: + ata_host_undo_start(host); + + return rc; } /** @@ -2735,6 +2744,10 @@ static int ahci_host_activate_multi_irqs(struct ata_host *host, * @host: target ATA host * @sht: scsi_host_template to use when registering the host * + * On failure, the ports are stopped again and the devres action + * registered by ata_host_start() is dropped without calling + * ->host_stop(), so releasing the host resources is left to the caller. + * * LOCKING: * Inherited from calling layer (may sleep). * diff --git a/drivers/ata/libahci_platform.c b/drivers/ata/libahci_platform.c index 6e072d681341..b44c0db4a86e 100644 --- a/drivers/ata/libahci_platform.c +++ b/drivers/ata/libahci_platform.c @@ -689,6 +689,10 @@ EXPORT_SYMBOL_GPL(ahci_platform_get_resources); * ahci-platform host, note any necessary resources (ie clks, phys, etc.) * must be initialized / enabled before calling this. * + * On failure, ->host_stop() is not called, so the caller has to release the + * resources it enabled (clocks, regulators, resets, PHYs) in its probe() + * error path. + * * RETURNS: * 0 on success otherwise a negative error code */ diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index f482c0a6d7e9..5b8dc89ed131 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -6127,6 +6127,46 @@ int ata_host_start(struct ata_host *host) } EXPORT_SYMBOL_GPL(ata_host_start); +/** + * ata_host_undo_start - undo ata_host_start() + * @host: ATA host to undo_start + * + * Stop the ports of @host and drop the devres action registered by + * ata_host_start(), without calling ->host_stop(). Nothing is done if + * @host has not been started. + * + * This gives the release of the host resources back to the caller, which + * is what a driver whose probe() error path releases those resources + * itself needs when starting or activating the host fails. + * + * LOCKING: + * Inherited from calling layer (may sleep). + */ +void ata_host_undo_start(struct ata_host *host) +{ + int i; + + if (!(host->flags & ATA_HOST_STARTED)) + return; + + for (i = 0; i < host->n_ports; i++) { + struct ata_port *ap = host->ports[i]; + + if (ap->ops->port_stop) + ap->ops->port_stop(ap); + } + + /* + * Drop the action added by ata_host_start() without calling it. + * It does not exist if neither ->port_stop() nor ->host_stop() is + * implemented, in which case there is nothing to drop. + */ + devres_destroy(host->dev, ata_host_stop, NULL, NULL); + + host->flags &= ~ATA_HOST_STARTED; +} +EXPORT_SYMBOL_GPL(ata_host_undo_start); + /** * ata_host_init - Initialize a host struct for sas (ipr, libsas) * @host: host to initialize @@ -6201,6 +6241,12 @@ static void async_port_probe(void *data, async_cookie_t cookie) * starts ports, registers @host with ATA and SCSI layers and * probe registered devices. * + * On failure, the host remains started, i.e. the devres action + * registered by ata_host_start() is kept, so ->host_stop() is called by + * the driver core when probe() fails. A caller which releases the host + * resources in its own probe() error path must therefore call + * ata_host_undo_start(). + * * LOCKING: * Inherited from calling layer (may sleep). * @@ -6294,6 +6340,10 @@ EXPORT_SYMBOL_GPL(ata_host_register); * have set polling mode on the port. In this case, @irq_handler * should be NULL. * + * On failure, the ports are stopped again and the devres action + * registered by ata_host_start() is dropped without calling + * ->host_stop(), so releasing the host resources is left to the caller. + * * LOCKING: * Inherited from calling layer (may sleep). * @@ -6314,27 +6364,40 @@ int ata_host_activate(struct ata_host *host, int irq, /* Special case for polling mode */ if (!irq) { WARN_ON(irq_handler); - return ata_host_register(host, sht); + rc = ata_host_register(host, sht); + if (rc) + goto undo_start; + + return 0; } irq_desc = devm_kasprintf(host->dev, GFP_KERNEL, "%s[%s]", dev_driver_string(host->dev), dev_name(host->dev)); - if (!irq_desc) - return -ENOMEM; + if (!irq_desc) { + rc = -ENOMEM; + goto undo_start; + } rc = devm_request_irq(host->dev, irq, irq_handler, irq_flags, irq_desc, host); if (rc) - return rc; + goto undo_start; for (i = 0; i < host->n_ports; i++) ata_port_desc_misc(host->ports[i], irq); rc = ata_host_register(host, sht); - /* if failed, just free the IRQ and leave ports alone */ - if (rc) + if (rc) { + /* if failed, just free the IRQ and leave ports alone */ devm_free_irq(host->dev, irq, host); + goto undo_start; + } + + return 0; + +undo_start: + ata_host_undo_start(host); return rc; } diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c index 976e4e160494..d5ef0338735c 100644 --- a/drivers/ata/libata-sff.c +++ b/drivers/ata/libata-sff.c @@ -2267,6 +2267,11 @@ EXPORT_SYMBOL_GPL(ata_pci_sff_prepare_host); * hosts. This separate helper is necessary because SFF hosts * use two separate interrupts in legacy mode. * + * Note that, unlike ata_host_activate(), the devres action registered + * by ata_host_start() is kept on failure, i.e. ->host_stop() is called + * by the driver core when probe() fails. All callers of this function + * rely on that, none of them releases the host resources itself. + * * LOCKING: * Inherited from calling layer (may sleep). * diff --git a/drivers/ata/sata_fsl.c b/drivers/ata/sata_fsl.c index 70b210afd291..299b2c886cbe 100644 --- a/drivers/ata/sata_fsl.c +++ b/drivers/ata/sata_fsl.c @@ -1490,8 +1490,12 @@ static int sata_fsl_probe(struct platform_device *ofdev) * device discovery process, invoking our port_start() handler & * error_handler() to execute a dummy Softreset EH session */ - ata_host_activate(host, irq, sata_fsl_interrupt, SATA_FSL_IRQ_FLAG, - &sata_fsl_sht); + retval = ata_host_activate(host, irq, sata_fsl_interrupt, + SATA_FSL_IRQ_FLAG, &sata_fsl_sht); + if (retval) { + sata_fsl_host_stop(host); + return retval; + } host_priv->intr_coalescing.show = fsl_sata_intr_coalescing_show; host_priv->intr_coalescing.store = fsl_sata_intr_coalescing_store; diff --git a/drivers/ata/sata_qstor.c b/drivers/ata/sata_qstor.c index 4e7f5b2ff3f6..f38310b84f51 100644 --- a/drivers/ata/sata_qstor.c +++ b/drivers/ata/sata_qstor.c @@ -584,8 +584,12 @@ static int qs_ata_init_one(struct pci_dev *pdev, qs_host_init(host, board_idx); pci_set_master(pdev); - return ata_host_activate(host, pdev->irq, qs_intr, IRQF_SHARED, - &qs_ata_sht); + rc = ata_host_activate(host, pdev->irq, qs_intr, IRQF_SHARED, + &qs_ata_sht); + if (rc) + qs_host_stop(host); + + return rc; } module_pci_driver(qs_ata_pci_driver); diff --git a/include/linux/libata.h b/include/linux/libata.h index 313e96173b19..b1debcef4947 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -1147,6 +1147,7 @@ extern struct ata_host *ata_host_alloc_pinfo(struct device *dev, extern void ata_host_get(struct ata_host *host); extern void ata_host_put(struct ata_host *host); extern int ata_host_start(struct ata_host *host); +extern void ata_host_undo_start(struct ata_host *host); extern int ata_host_register(struct ata_host *host, const struct scsi_host_template *sht); extern int ata_host_activate(struct ata_host *host, int irq, -- 2.55.0