On Fri, Dec 07, 2012 at 01:40:56PM +0800, Zhang Yanfei wrote:
> This removes the sparse warning:
> arch/x86/kernel/crash.c:49:32: sparse: incompatible types in comparison expression (different address spaces)
>
> Reported-by: kbuild test robot <fengguang.wu at intel.com>
> Signed-off-by: Zhang Yanfei <zhangyanfei at cn.fujitsu.com>
> ---
> arch/x86/include/asm/kexec.h | 4 +++-
> arch/x86/kernel/crash.c | 4 ++--
> 2 files changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h
> index 28feeba..16882cd 100644
> --- a/arch/x86/include/asm/kexec.h
> +++ b/arch/x86/include/asm/kexec.h
> @@ -163,7 +163,9 @@ struct kimage_arch {
> };
> #endif
>
> -extern void (*crash_vmclear_loaded_vmcss)(void);
> +extern void __rcu (*crash_vmclear_loaded_vmcss)(void);
> +#define vmclear_func_rcu(vmclear_func) \
> + ((void (*)(void)) rcu_dereference(vmclear_func))
>
> #endif /* __ASSEMBLY__ */
>
> diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
> index 2f6b8e8..50ce1d6 100644
> --- a/arch/x86/kernel/crash.c
> +++ b/arch/x86/kernel/crash.c
> @@ -38,7 +38,7 @@ int in_crash_kexec;
> *
> * protected by rcu.
> */
> -void (*crash_vmclear_loaded_vmcss)(void) = NULL;
> +void __rcu (*crash_vmclear_loaded_vmcss)(void) = NULL;
Isnt this (__rcu AS tag) sufficient? After all, sparse is complaining
about namespaces.
Creating a #define to cast seems excessive.
