Re: skb_splice_bits() and large chunks in pipe (was Re: xfs_file_splice_read: possible circular locking dependency detected

On Sun, Sep 18, 2016 at 3:31 PM, Al Viro [off-list ref] wrote:

What worries me is iov_iter_get_pages() and friends.

So honestly, if it worries you, I'm not going to complain at all if
you decide that you'd rather translate the pipe_buffer[] array into a
kvec by always splitting at page boundaries.

Even with large packets in networking, it's not going t be a huge
deal. And maybe we *should* make it a rule that a "kvec" is always
composed of individual entries that fit entirely within a page.

In this code, being safe rather than clever would be a welcome and
surprising change, I guess.

             Linus