Subject: Re: [PATCH net-next] tcp: Revert no longer abort SYN_SENT when receiving some ICMP

From: Leon Romanovsky <[email-masked]>
Date: Tue, 9 Jan 2024 15:26:06 +0200

On Mon, Jan 08, 2024 at 04:52:39PM +0100, Eric Dumazet wrote:
> On Tue, Jan 2, 2024 at 10:01 AM Leon Romanovsky <[email-masked]> wrote:
> >
> > From: Shachar Kagan <[email-masked]>
> >
> > This reverts commit 0a8de364ff7a14558e9676f424283148110384d6.
> >
> > Shachar reported that Vagrant (https://www.vagrantup.com/), which is
> > very popular tool to manage fleet of VMs stopped to work after commit
> > citied in Fixes line.
> >
> > The issue appears while using Vagrant to manage nested VMs.
> > The steps are:
> > * create vagrant file
> > * vagrant up
> > * vagrant halt (VM is created but shut down)
> > * vagrant up - fail
> >
> > Vagrant up stdout:
> > Bringing machine 'player1' up with 'libvirt' provider...
> > ==> player1: Creating shared folders metadata...
> > ==> player1: Starting domain.
> > ==> player1: Domain launching with graphics connection settings...
> > ==> player1:  -- Graphics Port:      5900
> > ==> player1:  -- Graphics IP:        127.0.0.1
> > ==> player1:  -- Graphics Password:  Not defined
> > ==> player1:  -- Graphics Websocket: 5700
> > ==> player1: Waiting for domain to get an IP address...
> > ==> player1: Waiting for machine to boot. This may take a few minutes...
> >     player1: SSH address: 192.168.123.61:22
> >     player1: SSH username: vagrant
> >     player1: SSH auth method: private key
> > ==> player1: Attempting graceful shutdown of VM...
> > ==> player1: Attempting graceful shutdown of VM...
> > ==> player1: Attempting graceful shutdown of VM...
> >     player1: Guest communication could not be established! This is usually because
> >     player1: SSH is not running, the authentication information was changed,
> >     player1: or some other networking issue. Vagrant will force halt, if
> >     player1: capable.
> > ==> player1: Attempting direct shutdown of domain...
> >
> > Fixes: 0a8de364ff7a ("tcp: no longer abort SYN_SENT when receiving some ICMP")
> > Closes: https://lore.kernel.org/all/[email-masked]
> > Signed-off-by: Shachar Kagan <[email-masked]>
> > Signed-off-by: Leon Romanovsky <[email-masked]>
> > ---
> 
> While IPv6 code has an issue (not calling tcp_ld_RTO_revert() helper
> for TCP_SYN_SENT as intended,
> I could not find the root cause for your case.
> 
> We will submit the patch again for 6.9, once we get to the root cause.

Feel free to send to Shachar with CC me and/or Gal any patches which you
would like to test in advance and we will be happy to do it.

> 
> Reviewed-by: Eric Dumazet <[email-masked]>

Thanks