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Date: Mon, 13 Jun 2016 16:40:51 +0100
From: Al Viro <viro@ZenIV.linux.org.uk>
To: dongke di <didongke@gmail.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: kern_path() returns error in kernel 4.4
Message-ID: <20160613154050.GV14480@ZenIV.linux.org.uk>
References: <CAN93O9pogTCwAwz=QWY19SnARUL=heP7EB7ENzxvNaA5MevNDQ@mail.gmail.com>
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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...