From mboxrd@z Thu Jan  1 00:00:00 1970
From: Massimo Maggi <me@massimo-maggi.eu>
Subject: Posix ACL on non-GPL modules.
Date: Sat, 12 Oct 2013 01:30:35 +0200
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Dear Sirs,
Every Posix ACL-related symbol is currently exported also for non-GPL
modules.
But the quite important function "posix_acl_release", declared inline in
include/linux/posix_acl.h, uses the GPL-only symbol "kfree_call_rcu".
So Posix ACL-related functionalities can't be used from non-GPL modules.
Can someone please clarify this situation? It seems an unwanted side-effect.
Small example pasted at the end of this message.
If this is effectively unwanted and a fix gets pulled by Linus, can
someone recommend a workaround for older kernels?

Thank you,
Massimo Maggi
PS:I'm interested in using Posix ACL functions from code in another Open
Source Initiative-approved license, NOT in proprietary closed-source code.

Building this module:
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/posix_acl.h>

MODULE_LICENSE("CDDL");

static int __init startup(void)
{
        struct posix_acl *a = posix_acl_alloc(1,0);
        //DO SOMETHING POTENTIALLY USEFUL
        posix_acl_release(a);
        return 0;
}


module_init(startup);

Leads to this error:
FATAL: modpost: GPL-incompatible module testmodule.ko uses GPL-only
symbol 'kfree_call_rcu'