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Date:   Sun, 12 Jun 2022 14:37:44 +0100
In-Reply-To: <de4521a5-aeb6-6b92-358b-be910029c1b7@redhat.com>
Message-Id: <20220612133744.4030602-1-pterjan@google.com>
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References: <de4521a5-aeb6-6b92-358b-be910029c1b7@redhat.com>
Subject: [PATCH v2] vboxguest: Do not use devm for irq
From:   Pascal Terjan <pterjan@google.com>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Hans de Goede <hdegoede@redhat.com>,
        Arnd Bergmann <arnd@arndb.de>
Cc:     linux-kernel@vger.kernel.org, Pascal Terjan <pterjan@google.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

When relying on devm it doesn't get freed early enough which causes the
following warning when unloading the module:

[249348.837181] remove_proc_entry: removing non-empty directory 'irq/20', leaking at least 'vboxguest'
[249348.837219] WARNING: CPU: 0 PID: 6708 at fs/proc/generic.c:715 remove_proc_entry+0x119/0x140

[249348.837379] Call Trace:
[249348.837385]  unregister_irq_proc+0xbd/0xe0
[249348.837392]  free_desc+0x23/0x60
[249348.837396]  irq_free_descs+0x4a/0x70
[249348.837401]  irq_domain_free_irqs+0x160/0x1a0
[249348.837452]  mp_unmap_irq+0x5c/0x60
[249348.837458]  acpi_unregister_gsi_ioapic+0x29/0x40
[249348.837463]  acpi_unregister_gsi+0x17/0x30
[249348.837467]  acpi_pci_irq_disable+0xbf/0xe0
[249348.837473]  pcibios_disable_device+0x20/0x30
[249348.837478]  pci_disable_device+0xef/0x120
[249348.837482]  vbg_pci_remove+0x6c/0x70 [vboxguest]

Signed-off-by: Pascal Terjan <pterjan@google.com>
---
v2: stop using devm rather than adding a manual devm_free_irq

 drivers/virt/vboxguest/vboxguest_linux.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/virt/vboxguest/vboxguest_linux.c b/drivers/virt/vboxguest/vboxguest_linux.c
index 6e8c0f1c1056..dec36934d679 100644
--- a/drivers/virt/vboxguest/vboxguest_linux.c
+++ b/drivers/virt/vboxguest/vboxguest_linux.c
@@ -360,8 +360,8 @@ static int vbg_pci_probe(struct pci_dev *pci, const struct pci_device_id *id)
 		goto err_vbg_core_exit;
 	}
 
-	ret = devm_request_irq(dev, pci->irq, vbg_core_isr, IRQF_SHARED,
-			       DEVICE_NAME, gdev);
+	ret = request_irq(pci->irq, vbg_core_isr, IRQF_SHARED, DEVICE_NAME,
+			  gdev);
 	if (ret) {
 		vbg_err("vboxguest: Error requesting irq: %d\n", ret);
 		goto err_vbg_core_exit;
@@ -371,7 +371,7 @@ static int vbg_pci_probe(struct pci_dev *pci, const struct pci_device_id *id)
 	if (ret) {
 		vbg_err("vboxguest: Error misc_register %s failed: %d\n",
 			DEVICE_NAME, ret);
-		goto err_vbg_core_exit;
+		goto err_free_irq;
 	}
 
 	ret = misc_register(&gdev->misc_device_user);
@@ -407,6 +407,8 @@ static int vbg_pci_probe(struct pci_dev *pci, const struct pci_device_id *id)
 	misc_deregister(&gdev->misc_device_user);
 err_unregister_misc_device:
 	misc_deregister(&gdev->misc_device);
+err_free_irq:
+	free_irq(pci->irq, gdev);
 err_vbg_core_exit:
 	vbg_core_exit(gdev);
 err_disable_pcidev:
@@ -423,6 +425,7 @@ static void vbg_pci_remove(struct pci_dev *pci)
 	vbg_gdev = NULL;
 	mutex_unlock(&vbg_gdev_mutex);
 
+	free_irq(pci->irq, gdev);
 	device_remove_file(gdev->dev, &dev_attr_host_features);
 	device_remove_file(gdev->dev, &dev_attr_host_version);
 	misc_deregister(&gdev->misc_device_user);
-- 
2.36.1.476.g0c4daa206d-goog