[Devel] Re: [PATCH] NFS: hard-code init_net for NFS callback transports

[J. Bruce Fields]

On Mon, Jun 11, 2012 at 08:37:18AM -0400, J. Bruce Fields wrote:
> On Fri, Jun 01, 2012 at 01:55:47PM +0400, Stanislav Kinsbursky wrote:
> > This patch set is a bug fix for Bruce's 3.5 branch.
> > I'll rebase this for 3.4 and resend.
> 
> Apologies for neglecting this, I'm done with the bakeathon and should be
> back to this soon.
> 
> But, I'm a bit confused: you say you'll rebase this, but I've only seen
> two rebased patches for 3.4, and neither looks like a simple rebase of
> this one.

Oh, I see; the backport of "SUNRPC: new svc_bind() routine introduced"
is a combination of the patch by the same name upstream with this one.

In future for backports I'd rather keep a one-to-one correspondance
between the original patches and the backported patches.  (Even if that
means 4.2 might not be as "bisectable".)

Also, get this patch into stable by just adding a "cc:
stable at vger.kernel.org" with the signed-off at the end of this patch.

I've gone ahead and fixed that up; results in the "for-3.4" and
"for-3.5" branches of

	git://linux-nfs.org/~bfields/linux-topics.git

Let me know if anything looks wrong.

--b.

> 
> OK, I'll look more closely and probably I'll figure out.  But in
> general, a little more detail in changelogs would help me process
> patches more quickly:
> 
> 	- Please make sure it's clear whether a given patch is a bug
> 	  fix, a new feature, or code reshuffling that isn't intended to
> 	  change behavior.  If it's a bug fix, tell me whether we've had
> 	  the bug forever or whether it's a recent regression.  And
> 	  (relevant here) if it's a recent regression, reference the ID
> 	  of the commit that introduced it.
> 	- If something is a backport, please reference in the changelog
> 	  the commit ID of the backported patch, especially if it's not
> 	  obviously the same.
> 
> --b.
> 	
> 
> > 
> > In case of destroying mount namespace on child reaper exit, nsproxy is zeroed
> > to the point already. So, dereferencing of it is invalid.
> > This patch hard-code "init_net" for all network namespace references for NFS
> > callback services. This will be fixed with proper NFS callback
> > containerization.
> > 
> > Signed-off-by: Stanislav Kinsbursky <skinsbursky at parallels.com>
> > ---
> >  fs/nfs/callback.c |   11 +++++------
> >  1 files changed, 5 insertions(+), 6 deletions(-)
> > 
> > diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
> > index 970659d..23ff18f 100644
> > --- a/fs/nfs/callback.c
> > +++ b/fs/nfs/callback.c
> > @@ -17,7 +17,6 @@
> >  #include <linux/kthread.h>
> >  #include <linux/sunrpc/svcauth_gss.h>
> >  #include <linux/sunrpc/bc_xprt.h>
> > -#include <linux/nsproxy.h>
> >  
> >  #include <net/inet_sock.h>
> >  
> > @@ -107,7 +106,7 @@ nfs4_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
> >  {
> >  	int ret;
> >  
> > -	ret = svc_create_xprt(serv, "tcp", xprt->xprt_net, PF_INET,
> > +	ret = svc_create_xprt(serv, "tcp", &init_net, PF_INET,
> >  				nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
> >  	if (ret <= 0)
> >  		goto out_err;
> > @@ -115,7 +114,7 @@ nfs4_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
> >  	dprintk("NFS: Callback listener port = %u (af %u)\n",
> >  			nfs_callback_tcpport, PF_INET);
> >  
> > -	ret = svc_create_xprt(serv, "tcp", xprt->xprt_net, PF_INET6,
> > +	ret = svc_create_xprt(serv, "tcp", &init_net, PF_INET6,
> >  				nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
> >  	if (ret > 0) {
> >  		nfs_callback_tcpport6 = ret;
> > @@ -184,7 +183,7 @@ nfs41_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
> >  	 * fore channel connection.
> >  	 * Returns the input port (0) and sets the svc_serv bc_xprt on success
> >  	 */
> > -	ret = svc_create_xprt(serv, "tcp-bc", xprt->xprt_net, PF_INET, 0,
> > +	ret = svc_create_xprt(serv, "tcp-bc", &init_net, PF_INET, 0,
> >  			      SVC_SOCK_ANONYMOUS);
> >  	if (ret < 0) {
> >  		rqstp = ERR_PTR(ret);
> > @@ -254,7 +253,7 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
> >  	char svc_name[12];
> >  	int ret = 0;
> >  	int minorversion_setup;
> > -	struct net *net = current->nsproxy->net_ns;
> > +	struct net *net = &init_net;
> >  
> >  	mutex_lock(&nfs_callback_mutex);
> >  	if (cb_info->users++ || cb_info->task != NULL) {
> > @@ -330,7 +329,7 @@ void nfs_callback_down(int minorversion)
> >  	cb_info->users--;
> >  	if (cb_info->users == 0 && cb_info->task != NULL) {
> >  		kthread_stop(cb_info->task);
> > -		svc_shutdown_net(cb_info->serv, current->nsproxy->net_ns);
> > +		svc_shutdown_net(cb_info->serv, &init_net);
> >  		svc_exit_thread(cb_info->rqst);
> >  		cb_info->serv = NULL;
> >  		cb_info->rqst = NULL;
> >