Re: [PATCH] xen/pvcalls: use WARN_ON(1) instead of __WARN()

[Boris Ostrovsky]

On 07/21/2017 12:17 PM, Arnd Bergmann wrote:
> __WARN() is an internal helper that is only available on
> some architectures, but causes a build error e.g. on ARM64
> in some configurations:
>
> drivers/xen/pvcalls-back.c: In function 'set_backend_state':
> drivers/xen/pvcalls-back.c:1097:5: error: implicit declaration of function '__WARN' [-Werror=implicit-function-declaration]
>
> Unfortunately, there is no equivalent of BUG() that takes no
> arguments, but WARN_ON(1) is commonly used in other drivers
> and works on all configurations.
>
> Fixes: 7160378206b2 ("xen/pvcalls: xenbus state handling")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>