Re: [PATCH] livepatch: use FTRACE_OPS_FL_IPMODIFY

[Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>]

(2014/12/19 0:49), Josh Poimboeuf wrote:
> On Thu, Dec 18, 2014 at 08:55:21PM +0900, Masami Hiramatsu wrote:
>> (2014/12/17 2:58), Seth Jennings wrote:
>>> changes in v7:
>>> - TODO: set IPMODIFY (not a blocker to moving forward)
>>
>> Why don't you set this?
>> IPMODIFY series are not completely applied yet, but you can already
>> use the flag. All you need is just set it :)
> 
> Yeah, I don't see any reason why we can't start using this flag now.
> How about we add this patch to the queue?
> 
> -->8--
> 
> Subject: livepatch: use FTRACE_OPS_FL_IPMODIFY
> 
> Use the FTRACE_OPS_FL_IPMODIFY flag to prevent conflicts with other
> ftrace users who also modify regs->ip.
> 
> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>

Looks good to me :)

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>

Thanks!

> ---
>  kernel/livepatch/core.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
> index 0004a71..bdd99975 100644
> --- a/kernel/livepatch/core.c
> +++ b/kernel/livepatch/core.c
> @@ -640,7 +640,8 @@ static int klp_init_func(struct klp_object *obj, struct klp_func *func)
>  
>  	ops->private = func;
>  	ops->func = klp_ftrace_handler;
> -	ops->flags = FTRACE_OPS_FL_SAVE_REGS | FTRACE_OPS_FL_DYNAMIC;
> +	ops->flags = FTRACE_OPS_FL_SAVE_REGS | FTRACE_OPS_FL_DYNAMIC |
> +		     FTRACE_FL_IPMODIFY;
>  	func->fops = ops;
>  	func->state = KLP_DISABLED;
>  
> 


-- 
Masami HIRAMATSU
Software Platform Research Dept. Linux Technology Research Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: masami.hiramatsu.pt@hitachi.com