Subject: Re: [PATCHv4 bpf-next 1/5] kallsyms: Fully export kallsyms_on_each_symbol function

From: Masami Hiramatsu <[email-masked]>
Date: Fri, 29 Apr 2022 23:51:45 +0900

On Thu, 28 Apr 2022 22:12:03 +0200
Jiri Olsa <[email-masked]> wrote:

> Fully exporting kallsyms_on_each_symbol function, so it can be used
> in following changes.
> 
> Rather than adding another ifdef option let's export the function
> completely (when CONFIG_KALLSYMS option is defined).
> 

This looks good to me.

Reviewed-by: Masami Hiramatsu <[email-masked]>

Thanks!

> Cc: Christoph Hellwig <[email-masked]>
> Signed-off-by: Jiri Olsa <[email-masked]>
> ---
>  include/linux/kallsyms.h | 7 ++++++-
>  kernel/kallsyms.c        | 2 --
>  2 files changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/include/linux/kallsyms.h b/include/linux/kallsyms.h
> index ce1bd2fbf23e..89f063651192 100644
> --- a/include/linux/kallsyms.h
> +++ b/include/linux/kallsyms.h
> @@ -65,11 +65,11 @@ static inline void *dereference_symbol_descriptor(void *ptr)
>  	return ptr;
>  }
>  
> +#ifdef CONFIG_KALLSYMS
>  int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
>  				      unsigned long),
>  			    void *data);
>  
> -#ifdef CONFIG_KALLSYMS
>  /* Lookup the address for a symbol. Returns 0 if not found. */
>  unsigned long kallsyms_lookup_name(const char *name);
>  
> @@ -163,6 +163,11 @@ static inline bool kallsyms_show_value(const struct cred *cred)
>  	return false;
>  }
>  
> +static inline int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *, unsigned long),
> +					  void *data)
> +{
> +	return -EOPNOTSUPP;
> +}
>  #endif /*CONFIG_KALLSYMS*/
>  
>  static inline void print_ip_sym(const char *loglvl, unsigned long ip)
> diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
> index 79f2eb617a62..fdfd308bebc4 100644
> --- a/kernel/kallsyms.c
> +++ b/kernel/kallsyms.c
> @@ -228,7 +228,6 @@ unsigned long kallsyms_lookup_name(const char *name)
>  	return module_kallsyms_lookup_name(name);
>  }
>  
> -#ifdef CONFIG_LIVEPATCH
>  /*
>   * Iterate over all symbols in vmlinux.  For symbols from modules use
>   * module_kallsyms_on_each_symbol instead.
> @@ -251,7 +250,6 @@ int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
>  	}
>  	return 0;
>  }
> -#endif /* CONFIG_LIVEPATCH */
>  
>  static unsigned long get_symbol_pos(unsigned long addr,
>  				    unsigned long *symbolsize,
> -- 
> 2.35.1
> 

-- 
Masami Hiramatsu <[email-masked]>