| Message ID | 20211229031245.582451-1-xu.xin16@zte.com.cn (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [linux-next] Documentation: fix outdated interpretation of ip_no_pmtu_disc | expand |
On Wed, 29 Dec 2021 03:12:45 +0000 cgel.zte@gmail.com wrote: > From: xu xin <xu.xin16@zte.com.cn> > > The updating way of pmtu has changed, but documentation is still in the > old way. See commit-id 28d35bcdd3925e7293408cdb8aa5f2aac5f0d6e3. So This not a correct way to quote a commit, please use: %h (\"%s\") as the format. > patch fix interpretation of ip_no_pmtu_disc. > > Besides, min_pmtu seems not to be discoverd, but set. > > Reported-by: Zeal Robot <zealci@zte.com.cn> How does the bot discover this sort of problem? > Signed-off-by: xu xin <xu.xin16@zte.com.cn> > --- > Documentation/networking/ip-sysctl.rst | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst > index c04431144f7a..dd5e53318805 100644 > --- a/Documentation/networking/ip-sysctl.rst > +++ b/Documentation/networking/ip-sysctl.rst > @@ -25,9 +25,11 @@ ip_default_ttl - INTEGER > ip_no_pmtu_disc - INTEGER > Disable Path MTU Discovery. If enabled in mode 1 and a > fragmentation-required ICMP is received, the PMTU to this > - destination will be set to min_pmtu (see below). You will need > - to raise min_pmtu to the smallest interface MTU on your system > - manually if you want to avoid locally generated fragments. > + destination will be set to the smallest of the old MTU > + and ip_rt_min_pmtu (see __ip_rt_update_pmtu() in I don't see how this is a meaningful distinction to someone reading this documentation, more of a corner case. > + net/ipv4/route.c). You will need to raise min_pmtu to the > + smallest interface MTU on your system manually if you want to > + avoid locally generated fragments. Use tabs instead of spaces. > In mode 2 incoming Path MTU Discovery messages will be > discarded. Outgoing frames are handled the same as in mode 1, > @@ -49,7 +51,7 @@ ip_no_pmtu_disc - INTEGER > Default: FALSE > > min_pmtu - INTEGER > - default 552 - minimum discovered Path MTU > + default 552 - minimum set Path MTU Also not must of an improvement IMHO. > ip_forward_use_pmtu - BOOLEAN > By default we don't trust protocol path MTUs while forwarding
diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst index c04431144f7a..dd5e53318805 100644 --- a/Documentation/networking/ip-sysctl.rst +++ b/Documentation/networking/ip-sysctl.rst @@ -25,9 +25,11 @@ ip_default_ttl - INTEGER ip_no_pmtu_disc - INTEGER Disable Path MTU Discovery. If enabled in mode 1 and a fragmentation-required ICMP is received, the PMTU to this - destination will be set to min_pmtu (see below). You will need - to raise min_pmtu to the smallest interface MTU on your system - manually if you want to avoid locally generated fragments. + destination will be set to the smallest of the old MTU + and ip_rt_min_pmtu (see __ip_rt_update_pmtu() in + net/ipv4/route.c). You will need to raise min_pmtu to the + smallest interface MTU on your system manually if you want to + avoid locally generated fragments. In mode 2 incoming Path MTU Discovery messages will be discarded. Outgoing frames are handled the same as in mode 1, @@ -49,7 +51,7 @@ ip_no_pmtu_disc - INTEGER Default: FALSE min_pmtu - INTEGER - default 552 - minimum discovered Path MTU + default 552 - minimum set Path MTU ip_forward_use_pmtu - BOOLEAN By default we don't trust protocol path MTUs while forwarding