Re: [PATCH v3] Add 4 tracepoint events for vfs

[Al Viro]

On Thu, Jan 31, 2013 at 03:40:38PM +0800, chenggang.qin@xxxxxxxxx wrote:
> @@ -1391,12 +1394,16 @@ generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
>  	unsigned long seg = 0;
>  	size_t count;
>  	loff_t *ppos = &iocb->ki_pos;
> +	const unsigned char *f_name;
>  
>  	count = 0;
>  	retval = generic_segment_checks(iov, &nr_segs, &count, VERIFY_WRITE);
>  	if (retval)
>  		return retval;
>  
> +	f_name = filp->f_path.dentry->d_name.name;
> +	trace_generic_file_aio_read(pos, iov_length(iov, nr_segs), f_name);

And just what is going to prevent that f_name of yours from being freed
just as you are passing it to the function you are calling?

IOW, NAK.  BTW, I would like to point out that *ANY* hooks in VFS have all
the stability granted to driver API - removal fodder whenever it becomes
convenient.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/