[PATCH v2] usb: xhci: remove the code build warning

[PATCH v2] usb: xhci: remove the code build warning

[Dongjiu Geng]

Initialize the 'err' variate to remove the build warning,
the warning is shown as below:

drivers/usb/host/xhci-tegra.c: In function 'tegra_xusb_mbox_thread':
drivers/usb/host/xhci-tegra.c:552:6: warning: 'err' may be used uninitialized in this function [-Wuninitialized]
drivers/usb/host/xhci-tegra.c:482:6: note: 'err' was declared here

Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com>
Acked-by: Thierry Reding <treding@nvidia.com>
---
How to reproduce:
1. make defconfig ARCH=arm
2. make -j100 CROSS_COMPILE=arm-linux-gnueabi- ARCH=arm

Then you can see below warnings:
drivers/usb/host/xhci-tegra.c: In function 'tegra_xusb_mbox_thread':
drivers/usb/host/xhci-tegra.c:552:6: warning: 'err' may be used uninitialized in this function [-Wuninitialized]
drivers/usb/host/xhci-tegra.c:482:6: note: 'err' was declared here
---
 drivers/usb/host/xhci-tegra.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-tegra.c
index a8c1d07..d50549f 100644
--- a/drivers/usb/host/xhci-tegra.c
+++ b/drivers/usb/host/xhci-tegra.c
@@ -481,7 +481,7 @@ static void tegra_xusb_mbox_handle(struct tegra_xusb *tegra,
 	unsigned long mask;
 	unsigned int port;
 	bool idle, enable;
-	int err;
+	int err = 0;
 
 	memset(&rsp, 0, sizeof(rsp));
 
-- 
1.9.1

Re: [PATCH v2] usb: xhci: remove the code build warning

[gengdongjiu]

Hi Mathias,
   This patch is ready to apply, It is great that this patch can be applied to 4.18. thanks a lot.

On 2018/6/6 22:36, Dongjiu Geng wrote:
> Initialize the 'err' variate to remove the build warning,
> the warning is shown as below:
> 
> drivers/usb/host/xhci-tegra.c: In function 'tegra_xusb_mbox_thread':
> drivers/usb/host/xhci-tegra.c:552:6: warning: 'err' may be used uninitialized in this function [-Wuninitialized]
> drivers/usb/host/xhci-tegra.c:482:6: note: 'err' was declared here
> 
> Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com>
> Acked-by: Thierry Reding <treding@nvidia.com>
> ---
> How to reproduce:
> 1. make defconfig ARCH=arm
> 2. make -j100 CROSS_COMPILE=arm-linux-gnueabi- ARCH=arm
> 
> Then you can see below warnings:
> drivers/usb/host/xhci-tegra.c: In function 'tegra_xusb_mbox_thread':
> drivers/usb/host/xhci-tegra.c:552:6: warning: 'err' may be used uninitialized in this function [-Wuninitialized]
> drivers/usb/host/xhci-tegra.c:482:6: note: 'err' was declared here
> ---
>  drivers/usb/host/xhci-tegra.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-tegra.c
> index a8c1d07..d50549f 100644
> --- a/drivers/usb/host/xhci-tegra.c
> +++ b/drivers/usb/host/xhci-tegra.c
> @@ -481,7 +481,7 @@ static void tegra_xusb_mbox_handle(struct tegra_xusb *tegra,
>  	unsigned long mask;
>  	unsigned int port;
>  	bool idle, enable;
> -	int err;
> +	int err = 0;
>  
>  	memset(&rsp, 0, sizeof(rsp));
>  
> 

Re: [PATCH v2] usb: xhci: remove the code build warning

[Greg KH]

On Wed, Jun 06, 2018 at 10:36:59PM +0800, Dongjiu Geng wrote:
> Initialize the 'err' variate to remove the build warning,
> the warning is shown as below:
> 
> drivers/usb/host/xhci-tegra.c: In function 'tegra_xusb_mbox_thread':
> drivers/usb/host/xhci-tegra.c:552:6: warning: 'err' may be used uninitialized in this function [-Wuninitialized]
> drivers/usb/host/xhci-tegra.c:482:6: note: 'err' was declared here
> 
> Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com>
> Acked-by: Thierry Reding <treding@nvidia.com>
> ---
> How to reproduce:
> 1. make defconfig ARCH=arm
> 2. make -j100 CROSS_COMPILE=arm-linux-gnueabi- ARCH=arm
> 
> Then you can see below warnings:
> drivers/usb/host/xhci-tegra.c: In function 'tegra_xusb_mbox_thread':
> drivers/usb/host/xhci-tegra.c:552:6: warning: 'err' may be used uninitialized in this function [-Wuninitialized]
> drivers/usb/host/xhci-tegra.c:482:6: note: 'err' was declared here

What changed from v1?  Always put that below the --- line.

Please fix up and resend a v3.

thanks,

greg k-h

答复: [PATCH v2] usb: xhci: remove the code build warning

[gengdongjiu]

> On Wed, Jun 06, 2018 at 10:36:59PM +0800, Dongjiu Geng wrote:
> > Initialize the 'err' variate to remove the build warning, the warning
> > is shown as below:
> >
> > drivers/usb/host/xhci-tegra.c: In function 'tegra_xusb_mbox_thread':
> > drivers/usb/host/xhci-tegra.c:552:6: warning: 'err' may be used
> > uninitialized in this function [-Wuninitialized]
> > drivers/usb/host/xhci-tegra.c:482:6: note: 'err' was declared here
> >
> > Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com>
> > Acked-by: Thierry Reding <treding@nvidia.com>
> > ---
> > How to reproduce:
> > 1. make defconfig ARCH=arm
> > 2. make -j100 CROSS_COMPILE=arm-linux-gnueabi- ARCH=arm
> >
> > Then you can see below warnings:
> > drivers/usb/host/xhci-tegra.c: In function 'tegra_xusb_mbox_thread':
> > drivers/usb/host/xhci-tegra.c:552:6: warning: 'err' may be used
> > uninitialized in this function [-Wuninitialized]
> > drivers/usb/host/xhci-tegra.c:482:6: note: 'err' was declared here
> 
> What changed from v1?  Always put that below the --- line.
> 
> Please fix up and resend a v3.


Thanks, I justly add "Acked-by: Thierry Reding <treding@nvidia.com>" in the V2 compared with v1
Anyway I will put that below and resend a v3.

> 
> thanks,
> 
> greg k-h