[PATCH] usb: host: ehci-atmel: stop clocks before releasing HCD

[PATCH] usb: host: ehci-atmel: stop clocks before releasing HCD

[Hongyan Xu]

usb_put_hcd() drops the driver's HCD reference and can free the HCD and its
private data. The remove callback then calls atmel_stop_ehci(), which
obtains that HCD from platform data and dereferences its private data to
disable the clocks.

Stop the controller clocks before dropping the HCD reference so that
atmel_stop_ehci() cannot access an already freed HCD.

Fixes: 501c9c0802d9 ("USB: at91: Add USB EHCI driver for at91sam9g45 series")
Signed-off-by: Hongyan Xu <getshell@seu.edu.cn>
---
 drivers/usb/host/ehci-atmel.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/usb/host/ehci-atmel.c b/drivers/usb/host/ehci-atmel.c
index 65747270fd88..bcd56f888ec9 100644
--- a/drivers/usb/host/ehci-atmel.c
+++ b/drivers/usb/host/ehci-atmel.c
@@ -177,9 +177,8 @@ static void ehci_atmel_drv_remove(struct platform_device *pdev)
 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
 
 	usb_remove_hcd(hcd);
-	usb_put_hcd(hcd);
-
 	atmel_stop_ehci(pdev);
+	usb_put_hcd(hcd);
 }
 
 static int __maybe_unused ehci_atmel_drv_suspend(struct device *dev)
-- 
2.50.1.windows.1

Re: [PATCH] usb: host: ehci-atmel: stop clocks before releasing HCD

[Greg Kroah-Hartman]

On Thu, Aug 06, 2026 at 02:05:57PM +0800, Hongyan Xu wrote:
> usb_put_hcd() drops the driver's HCD reference and can free the HCD and its
> private data. The remove callback then calls atmel_stop_ehci(), which
> obtains that HCD from platform data and dereferences its private data to
> disable the clocks.
> 
> Stop the controller clocks before dropping the HCD reference so that
> atmel_stop_ehci() cannot access an already freed HCD.
> 
> Fixes: 501c9c0802d9 ("USB: at91: Add USB EHCI driver for at91sam9g45 series")
> Signed-off-by: Hongyan Xu <getshell@seu.edu.cn>
> ---
>  drivers/usb/host/ehci-atmel.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)

You just sent a bunch of obviously-llm-helped patches without properly
attributing that.  Please resend new versions with the correct
information, AND correctly cc: the stable tree for when you have Fixes:
tags like this.

thanks,

greg k-h

Re: [PATCH] usb: host: ehci-atmel: stop clocks before releasing HCD

[Greg Kroah-Hartman]

On Thu, Aug 06, 2026 at 02:05:57PM +0800, Hongyan Xu wrote:
> usb_put_hcd() drops the driver's HCD reference and can free the HCD and its
> private data. The remove callback then calls atmel_stop_ehci(), which
> obtains that HCD from platform data and dereferences its private data to
> disable the clocks.
> 
> Stop the controller clocks before dropping the HCD reference so that
> atmel_stop_ehci() cannot access an already freed HCD.
> 
> Fixes: 501c9c0802d9 ("USB: at91: Add USB EHCI driver for at91sam9g45 series")
> Signed-off-by: Hongyan Xu <getshell@seu.edu.cn>
> ---
>  drivers/usb/host/ehci-atmel.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/host/ehci-atmel.c b/drivers/usb/host/ehci-atmel.c
> index 65747270fd88..bcd56f888ec9 100644
> --- a/drivers/usb/host/ehci-atmel.c
> +++ b/drivers/usb/host/ehci-atmel.c
> @@ -177,9 +177,8 @@ static void ehci_atmel_drv_remove(struct platform_device *pdev)
>  	struct usb_hcd *hcd = platform_get_drvdata(pdev);
>  
>  	usb_remove_hcd(hcd);
> -	usb_put_hcd(hcd);
> -
>  	atmel_stop_ehci(pdev);
> +	usb_put_hcd(hcd);
>  }
>  
>  static int __maybe_unused ehci_atmel_drv_suspend(struct device *dev)
> -- 
> 2.50.1.windows.1
> 
> 

How was this tested?

Re: [PATCH] usb: host: ehci-atmel: stop clocks before releasing HCD

[Alan Stern]

On Thu, Aug 06, 2026 at 02:05:57PM +0800, Hongyan Xu wrote:
> usb_put_hcd() drops the driver's HCD reference and can free the HCD and its
> private data. The remove callback then calls atmel_stop_ehci(), which
> obtains that HCD from platform data and dereferences its private data to
> disable the clocks.
> 
> Stop the controller clocks before dropping the HCD reference so that
> atmel_stop_ehci() cannot access an already freed HCD.
> 
> Fixes: 501c9c0802d9 ("USB: at91: Add USB EHCI driver for at91sam9g45 series")
> Signed-off-by: Hongyan Xu <getshell@seu.edu.cn>
> ---

Acked-by: Alan Stern <stern@rowland.harvard.edu>

>  drivers/usb/host/ehci-atmel.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/host/ehci-atmel.c b/drivers/usb/host/ehci-atmel.c
> index 65747270fd88..bcd56f888ec9 100644
> --- a/drivers/usb/host/ehci-atmel.c
> +++ b/drivers/usb/host/ehci-atmel.c
> @@ -177,9 +177,8 @@ static void ehci_atmel_drv_remove(struct platform_device *pdev)
>  	struct usb_hcd *hcd = platform_get_drvdata(pdev);
>  
>  	usb_remove_hcd(hcd);
> -	usb_put_hcd(hcd);
> -
>  	atmel_stop_ehci(pdev);
> +	usb_put_hcd(hcd);
>  }
>  
>  static int __maybe_unused ehci_atmel_drv_suspend(struct device *dev)
> -- 
> 2.50.1.windows.1
> 
>