From: David Miller <email@example.com> To: firstname.lastname@example.org Cc: email@example.com, firstname.lastname@example.org, email@example.com, firstname.lastname@example.org, email@example.com Subject: Re: [net] tipc: fix issues with early FAILOVER_MSG from peer Date: Tue, 18 Jun 2019 10:03:57 -0700 (PDT) Message-ID: <firstname.lastname@example.org> (raw) In-Reply-To: <email@example.com> From: Tuong Lien <firstname.lastname@example.org> Date: Mon, 17 Jun 2019 11:56:12 +0700 > It appears that a FAILOVER_MSG can come from peer even when the failure > link is resetting (i.e. just after the 'node_write_unlock()'...). This > means the failover procedure on the node has not been started yet. > The situation is as follows: ... > Once this happens, the link failover procedure will be triggered > wrongly on the receiving node since the node isn't in FAILINGOVER state > but then another link failover will be carried out. > The consequences are: > > 1) A peer might get stuck in FAILINGOVER state because the 'sync_point' > was set, reset and set incorrectly, the criteria to end the failover > would not be met, it could keep waiting for a message that has already > received. > > 2) The early FAILOVER_MSG(s) could be queued in the link failover > deferdq but would be purged or not pulled out because the 'drop_point' > was not set correctly. > > 3) The early FAILOVER_MSG(s) could be dropped too. > > 4) The dummy FAILOVER_MSG could make the peer leaving FAILINGOVER state > shortly, but later on it would be restarted. > > The same situation can also happen when the link is in PEER_RESET state > and a FAILOVER_MSG arrives. > > The commit resolves the issues by forcing the link down immediately, so > the failover procedure will be started normally (which is the same as > when receiving a FAILOVER_MSG and the link is in up state). > > Also, the function "tipc_node_link_failover()" is toughen to avoid such > a situation from happening. > > Acked-by: Jon Maloy <email@example.com> > Signed-off-by: Tuong Lien <firstname.lastname@example.org> Applied, thank you.
prev parent reply index Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top 2019-06-17 4:56 Tuong Lien 2019-06-18 17:03 ` David Miller [this message]
Reply instructions: You may reply publically to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --email@example.com \ --firstname.lastname@example.org \ --email@example.com \ --firstname.lastname@example.org \ --email@example.com \ --firstname.lastname@example.org \ --email@example.com \ --firstname.lastname@example.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: link
Netdev Archive on lore.kernel.org Archives are clonable: git clone --mirror https://lore.kernel.org/netdev/0 netdev/git/0.git git clone --mirror https://lore.kernel.org/netdev/1 netdev/git/1.git # If you have public-inbox 1.1+ installed, you may # initialize and index your mirror using the following commands: public-inbox-init -V2 netdev netdev/ https://lore.kernel.org/netdev \ email@example.com firstname.lastname@example.org public-inbox-index netdev Newsgroup available over NNTP: nntp://nntp.lore.kernel.org/org.kernel.vger.netdev AGPL code for this site: git clone https://public-inbox.org/ public-inbox