The tps65910_rtc data is registered as the platform driver data in _probe().
Therefore the tps65910_rtc should be used on unregistering the rtc device.
And device pointer should be retrieved from the platform_device structure.
This patch fixes the error as below.
Unable to handle kernel NULL pointer dereference at virtual address 00000008
Modules linked in: rtc_tps65910(-)
CPU: 0 Not tainted (3.7.0-rc7-next-20121128-g6b1f974-dirty #7)
PC is at tps65910_rtc_alarm_irq_enable+0x20/0x2c [rtc_tps65910]
LR is at tps65910_rtc_alarm_irq_enable+0x10/0x2c [rtc_tps65910]
[<bf000044>] (tps65910_rtc_alarm_irq_enable+0x20/0x2c [rtc_tps65910]) from
[<bf0004d4>] (tps65910_rtc_remove+0x18/0x28 [rtc_)
[<bf0004d4>] (tps65910_rtc_remove+0x18/0x28 [rtc_tps65910]) from
[<c034e700>] (platform_drv_remove+0x18/0x1c)
[<c034e700>] (platform_drv_remove+0x18/0x1c) from
[<c034ceec>] (__device_release_driver+0x70/0xcc)
[<c034ceec>] (__device_release_driver+0x70/0xcc) from
[<c034d608>] (driver_detach+0xb4/0xb8)
[<c034d608>] (driver_detach+0xb4/0xb8) from
[<c034cc24>] (bus_remove_driver+0x7c/0xc0)
[<c034cc24>] (bus_remove_driver+0x7c/0xc0) from
[<c00a045c>] (sys_delete_module+0x148/0x21c)
[<c00a045c>] (sys_delete_module+0x148/0x21c) from
[<c0013c60>] (ret_fast_syscall+0x0/0x3c)
Signed-off-by: Milo(Woogyom) Kim <[email protected]>
---
drivers/rtc/rtc-tps65910.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/rtc/rtc-tps65910.c b/drivers/rtc/rtc-tps65910.c
index e8d44bc..687006f 100644
--- a/drivers/rtc/rtc-tps65910.c
+++ b/drivers/rtc/rtc-tps65910.c
@@ -288,11 +288,11 @@ static int __devinit tps65910_rtc_probe(struct platform_device *pdev)
static int __devexit tps65910_rtc_remove(struct platform_device *pdev)
{
/* leave rtc running, but disable irqs */
- struct rtc_device *rtc = platform_get_drvdata(pdev);
+ struct tps65910_rtc *tps_rtc = platform_get_drvdata(pdev);
- tps65910_rtc_alarm_irq_enable(&rtc->dev, 0);
+ tps65910_rtc_alarm_irq_enable(&pdev->dev, 0);
- rtc_device_unregister(rtc);
+ rtc_device_unregister(tps_rtc->rtc);
return 0;
}
--
1.7.9.5
Best Regards,
Milo
> -----Original Message-----
> From: Kim, Milo [mailto:[email protected]]
> Sent: Thursday, November 29, 2012 7:36 AM
> To: Andrew Morton
> Cc: [email protected]; [email protected]; Venu Byravarasu;
> Sivaram Nair; [email protected]
> Subject: [PATCH] rtc-tps65910: fix invalid pointer access on _remove()
>
> The tps65910_rtc data is registered as the platform driver data in _probe().
> Therefore the tps65910_rtc should be used on unregistering the rtc device.
> And device pointer should be retrieved from the platform_device structure.
>
> This patch fixes the error as below.
>
> Unable to handle kernel NULL pointer dereference at virtual address
> 00000008
> Modules linked in: rtc_tps65910(-)
> CPU: 0 Not tainted (3.7.0-rc7-next-20121128-g6b1f974-dirty #7)
> PC is at tps65910_rtc_alarm_irq_enable+0x20/0x2c [rtc_tps65910]
> LR is at tps65910_rtc_alarm_irq_enable+0x10/0x2c [rtc_tps65910]
> [<bf000044>] (tps65910_rtc_alarm_irq_enable+0x20/0x2c [rtc_tps65910])
> from
> [<bf0004d4>] (tps65910_rtc_remove+0x18/0x28 [rtc_)
> [<bf0004d4>] (tps65910_rtc_remove+0x18/0x28 [rtc_tps65910]) from
> [<c034e700>] (platform_drv_remove+0x18/0x1c)
> [<c034e700>] (platform_drv_remove+0x18/0x1c) from
> [<c034ceec>] (__device_release_driver+0x70/0xcc)
> [<c034ceec>] (__device_release_driver+0x70/0xcc) from
> [<c034d608>] (driver_detach+0xb4/0xb8)
> [<c034d608>] (driver_detach+0xb4/0xb8) from
> [<c034cc24>] (bus_remove_driver+0x7c/0xc0)
> [<c034cc24>] (bus_remove_driver+0x7c/0xc0) from
> [<c00a045c>] (sys_delete_module+0x148/0x21c)
> [<c00a045c>] (sys_delete_module+0x148/0x21c) from
> [<c0013c60>] (ret_fast_syscall+0x0/0x3c)
>
> Signed-off-by: Milo(Woogyom) Kim <[email protected]>
> ---
> drivers/rtc/rtc-tps65910.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/rtc/rtc-tps65910.c b/drivers/rtc/rtc-tps65910.c
> index e8d44bc..687006f 100644
> --- a/drivers/rtc/rtc-tps65910.c
> +++ b/drivers/rtc/rtc-tps65910.c
> @@ -288,11 +288,11 @@ static int __devinit tps65910_rtc_probe(struct
> platform_device *pdev)
> static int __devexit tps65910_rtc_remove(struct platform_device *pdev)
> {
> /* leave rtc running, but disable irqs */
> - struct rtc_device *rtc = platform_get_drvdata(pdev);
> + struct tps65910_rtc *tps_rtc = platform_get_drvdata(pdev);
>
> - tps65910_rtc_alarm_irq_enable(&rtc->dev, 0);
> + tps65910_rtc_alarm_irq_enable(&pdev->dev, 0);
>
> - rtc_device_unregister(rtc);
> + rtc_device_unregister(tps_rtc->rtc);
> return 0;
> }
>
> --
> 1.7.9.5
>
>
> Best Regards,
> Milo
This change looks good to me.
Plz consider my ACK.
Acked-by: Venu Byravarasu <[email protected]>