Regression, was [PATCH 4/4] USB: host: ohci-at91: merge loops in ohci_hcd_at91_drv_probe

[Alexandre Belloni]

Hi Peter,

On 01/12/2015 at 18:17:16 +0100, Peter Rosin wrote :
> [<c02f5084>] (ohci_hcd_at91_overcurrent_irq) from [<c00433b0>] (handle_irq_event_percpu+0x78/0x140)
> [<c00433b0>] (handle_irq_event_percpu) from [<c00434a4>] (handle_irq_event+0x2c/0x40)
> [<c00434a4>] (handle_irq_event) from [<c00458b8>] (handle_simple_irq+0x6c/0x80)
> [<c00458b8>] (handle_simple_irq) from [<c0042bc4>] (generic_handle_irq+0x2c/0x3c)
> [<c0042bc4>] (generic_handle_irq) from [<c01fe4ac>] (gpio_irq_handler+0xa4/0x12c)
> [<c01fe4ac>] (gpio_irq_handler) from [<c0042bc4>] (generic_handle_irq+0x2c/0x3c)
> [<c0042bc4>] (generic_handle_irq) from [<c0042dec>] (__handle_domain_irq+0x54/0xa8)
> [<c0042dec>] (__handle_domain_irq) from [<c0013500>] (__irq_svc+0x40/0x54)
> [<c0013500>] (__irq_svc) from [<c004451c>] (__setup_irq+0x248/0x530)
> [<c004451c>] (__setup_irq) from [<c0044954>] (request_threaded_irq+0xc4/0x144)
> [<c0044954>] (request_threaded_irq) from [<c02f5a0c>] (ohci_hcd_at91_drv_probe+0x460/0x518)
> [<c02f5a0c>] (ohci_hcd_at91_drv_probe) from [<c02670ec>] (platform_drv_probe+0x44/0xa4)
> [<c02670ec>] (platform_drv_probe) from [<c02655b4>] (driver_probe_device+0x1fc/0x43c)
> [<c02655b4>] (driver_probe_device) from [<c0265880>] (__driver_attach+0x8c/0x90)
> [<c0265880>] (__driver_attach) from [<c0263880>] (bus_for_each_dev+0x6c/0xa0)
> [<c0263880>] (bus_for_each_dev) from [<c0264b80>] (bus_add_driver+0x1d0/0x268)
> [<c0264b80>] (bus_add_driver) from [<c0266078>] (driver_register+0x78/0xf8)
> [<c0266078>] (driver_register) from [<c00096c8>] (do_one_initcall+0xb8/0x1f0)
> [<c00096c8>] (do_one_initcall) from [<c068bda4>] (kernel_init_freeable+0x138/0x1d8)
> [<c068bda4>] (kernel_init_freeable) from [<c04d06f4>] (kernel_init+0x8/0xe8)
> [<c04d06f4>] (kernel_init) from [<c000ff68>] (ret_from_fork+0x14/0x2c)
> Code: e5916058 e1a08000 e3a04000 e2865008 (e5b50004)
> ---[ end trace e66fbc480972ac43 ]---
> Kernel panic - not syncing: Fatal exception in interrupt
> ---[ end Kernel panic - not syncing: Fatal exception in interrupt

I think I understood what happens. Can you try the following patch?

8<------
>From 402f8444bc92d218edc63dcc3c87459981a56c31 Mon Sep 17 00:00:00 2001
From: Alexandre Belloni <alexandre.belloni at free-electrons.com>
Date: Wed, 2 Dec 2015 18:49:34 +0100
Subject: [PATCH] USB: host: ohci-at91: fix a crash in
 ohci_hcd_at91_overcurrent_irq

Signed-off-by: Alexandre Belloni <alexandre.belloni at free-electrons.com>
---
 drivers/usb/host/ohci-at91.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/host/ohci-at91.c b/drivers/usb/host/ohci-at91.c
index 342ffd140122..8c6e15bd6ff0 100644
--- a/drivers/usb/host/ohci-at91.c
+++ b/drivers/usb/host/ohci-at91.c
@@ -473,6 +473,8 @@ static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
 	if (!pdata)
 		return -ENOMEM;
 
+	pdev->dev.platform_data = pdata;
+
 	if (!of_property_read_u32(np, "num-ports", &ports))
 		pdata->ports = ports;
 
@@ -483,6 +485,7 @@ static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
 		 */
 		if (i >= pdata->ports) {
 			pdata->vbus_pin[i] = -EINVAL;
+			pdata->overcurrent_pin[i] = -EINVAL;
 			continue;
 		}
 
@@ -513,10 +516,8 @@ static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
 	}
 
 	at91_for_each_port(i) {
-		if (i >= pdata->ports) {
-			pdata->overcurrent_pin[i] = -EINVAL;
-			continue;
-		}
+		if (i >= pdata->ports)
+			break;
 
 		pdata->overcurrent_pin[i] =
 			of_get_named_gpio_flags(np, "atmel,oc-gpio", i, &flags);
@@ -552,8 +553,6 @@ static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
 		}
 	}
 
-	pdev->dev.platform_data = pdata;
-
 	device_init_wakeup(&pdev->dev, 1);
 	return usb_hcd_at91_probe(&ohci_at91_hc_driver, pdev);
 }
-- 
2.5.0