Kuniyuki Iwashima c905dee622 tcp: Migrate TCP_NEW_SYN_RECV requests at retransmitting SYN+ACKs.
As with the preceding patch, this patch changes reqsk_timer_handler() to
call reuseport_migrate_sock() and inet_reqsk_clone() to migrate in-flight
requests at retransmitting SYN+ACKs. If we can select a new listener and
clone the request, we resume setting the SYN+ACK timer for the new req. If
we can set the timer, we call inet_ehash_insert() to unhash the old req and
put the new req into ehash.

The noteworthy point here is that by unhashing the old req, another CPU
processing it may lose the "own_req" race in tcp_v[46]_syn_recv_sock() and
drop the final ACK packet. However, the new timer will recover this
situation.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210612123224.12525-7-kuniyu@amazon.co.jp
2021-06-15 18:01:06 +02:00
2021-05-07 00:26:34 -07:00
2021-05-07 00:26:35 -07:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Description
No description provided
Readme 3.4 GiB
Languages
C 97%
Assembly 1%
Shell 0.6%
Rust 0.5%
Python 0.4%
Other 0.3%