Re: [PATCH net] mpls: fix af_mpls dependencies

Arnd Bergmann [off-list ref] writes:

On Fri, Jun 14, 2019 at 4:07 PM David Ahern [off-list ref] wrote:

quoted

On 6/14/19 8:01 AM, Arnd Bergmann wrote:

quoted

On Wed, Jun 12, 2019 at 9:41 AM Randy Dunlap [off-list ref] wrote:

quoted

On 6/11/19 5:08 PM, Matteo Croce wrote:

It clearly shouldn't select PROC_SYSCTL, but I think it should not
have a 'depends on' statement either. I think the correct fix for the
original problem would have been something like

--- a/net/mpls/af_mpls.c
+++ b/net/mpls/af_mpls.c

@@ -2659,6 +2659,9 @@ static int mpls_net_init(struct net *net)
        net->mpls.ip_ttl_propagate = 1;
        net->mpls.default_ttl = 255;

+       if (!IS_ENABLED(CONFIG_PROC_SYSCTL))
+               return 0;
+
        table = kmemdup(mpls_table, sizeof(mpls_table), GFP_KERNEL);
        if (table == NULL)
                return -ENOMEM;

Without sysctl, the entire mpls_router code is disabled. So if sysctl is
not enabled there is no point in building this file.

Ok, I see.

There are a couple of other drivers that use 'depends on SYSCTL',
which may be the right thing to do here. In theory, one can still
build a kernel with CONFIG_SYSCTRL_SYSCALL=y and no
procfs.

Which reminds me.  I really need to write the patch to remove
CONFIG_SYSCTL_SYSCALL.

Unless I have missed something we have finally reached default off in
all of the distributions so no one should care.

Eric