Re: kern_path() returns error in kernel 4.4

[Al Viro]

On Mon, Jun 13, 2016 at 05:12:27PM +0800, dongke di wrote:
> struct path path;
> int r = kern_path( "/tmp/abc.txt", LOOKUP_FOLLOW | LOOKUP_PARENT, &path );
> 
> The file abc.txt does not exist.
> 
> On Ubuntu 14.04 ( kernel 3.13 ), r is zero (succed).
> On Ubuntu 16.04 ( kernel 4.4 ), r is -2 ( fail).
> 
> Is it a bug or other else ?

It is - in the code that passes LOOKUP_PARENT to kern_path().  What are
is it trying to do there?  Need more context...