Re: Urgent: BUG: PPP ioctl Transport endpoint is not connected

On Wed, Dec 09, 2020 at 04:47:52PM +0200, Martin Zaharinov wrote:

Hi All

I have problem with latest kernel release 
And the problem is base on this late problem :


https://www.mail-archive.com/search?l=netdev@vger.kernel.org&q=subject:%22Re%5C%3A+ppp%5C%2Fpppoe%2C+still+panic+4.15.3+in+ppp_push%22&o=newest&f=1

I have same problem in kernel 5.6 > now I use kernel 5.9.13 and have same problem.


In kernel 5.9.13 now don’t have any crashes in dimes but in one moment accel service stop with defunct and in log have many of this line :


error: vlan608: ioctl(PPPIOCCONNECT): Transport endpoint is not connected
error: vlan617: ioctl(PPPIOCCONNECT): Transport endpoint is not connected
error: vlan679: ioctl(PPPIOCCONNECT): Transport endpoint is not connected

In one moment connected user bump double or triple and after that service defunct and need wait to drop all session to start .

I talk with accel-ppp team and they said this is kernel related problem and to back to kernel 4.14 there is not this problem.

Problem is come after kernel 4.15 > and not have solution to this moment.

I'm sorry, I don't understand.
Do you mean that v4.14 worked fine (no crash, no ioctl() error)?
Did the problem start appearing in v4.15? Or did v4.15 work and the
problem appeared in v4.16?

Please help to find the problem.

Last time in link I see is make changes in ppp_generic.c 

ppp_lock(ppp);
        spin_lock_bh(&pch->downl);
        if (!pch->chan) {
                /* Don't connect unregistered channels */
                spin_unlock_bh(&pch->downl);
                ppp_unlock(ppp);
                ret = -ENOTCONN;
                goto outl;
        }
        spin_unlock_bh(&pch->downl);


But this fix only to don’t display error and freeze system 
The problem is stay and is to big.

Do you use accel-ppp's unit-cache option? Does the problem go away if
you stop using it?

Please help to fix.