Skip to content

cloud-kernel
cloud-kernel

openanolis / cloud-kernel
1 年多 前同步成功

通知 161
Star 36
Fork 7
cloud-kernel
cloud-kernel
切换分支/标签
  1. 01 4月, 2018 3 次提交
  3. 30 3月, 2018 7 次提交
  5. 28 3月, 2018 1 次提交
  7. 27 3月, 2018 5 次提交
  9. 24 3月, 2018 1 次提交
  11. 23 3月, 2018 6 次提交
  13. 20 3月, 2018 2 次提交
  15. 17 3月, 2018 3 次提交
  17. 15 3月, 2018 1 次提交
    • S
      ipv4: lock mtu in fnhe when received PMTU < net.ipv4.route.min_pmtu · d52e5a7e
      由 Sabrina Dubroca 提交于 
      Prior to the rework of PMTU information storage in commit
2c8cec5c ("ipv4: Cache learned PMTU information in inetpeer."),
when a PMTU event advertising a PMTU smaller than
net.ipv4.route.min_pmtu was received, we would disable setting the DF
flag on packets by locking the MTU metric, and set the PMTU to
net.ipv4.route.min_pmtu.

Since then, we don't disable DF, and set PMTU to
net.ipv4.route.min_pmtu, so the intermediate router that has this link
with a small MTU will have to drop the packets.

This patch reestablishes pre-2.6.39 behavior by splitting
rtable->rt_pmtu into a bitfield with rt_mtu_locked and rt_pmtu.
rt_mtu_locked indicates that we shouldn't set the DF bit on that path,
and is checked in ip_dont_fragment().

One possible workaround is to set net.ipv4.route.min_pmtu to a value low
enough to accommodate the lowest MTU encountered.

Fixes: 2c8cec5c ("ipv4: Cache learned PMTU information in inetpeer.")
Signed-off-by: NSabrina Dubroca <sd@queasysnail.net>
Reviewed-by: NStefano Brivio <sbrivio@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      d52e5a7e
  19. 12 3月, 2018 1 次提交
    • X
      sock_diag: request _diag module only when the family or proto has been registered · bf2ae2e4
      由 Xin Long 提交于 
      Now when using 'ss' in iproute, kernel would try to load all _diag
modules, which also causes corresponding family and proto modules
to be loaded as well due to module dependencies.

Like after running 'ss', sctp, dccp, af_packet (if it works as a module)
would be loaded.

For example:

  $ lsmod|grep sctp
  $ ss
  $ lsmod|grep sctp
  sctp_diag              16384  0
  sctp                  323584  5 sctp_diag
  inet_diag              24576  4 raw_diag,tcp_diag,sctp_diag,udp_diag
  libcrc32c              16384  3 nf_conntrack,nf_nat,sctp

As these family and proto modules are loaded unintentionally, it
could cause some problems, like:

- Some debug tools use 'ss' to collect the socket info, which loads all
  those diag and family and protocol modules. It's noisy for identifying
  issues.

- Users usually expect to drop sctp init packet silently when they
  have no sense of sctp protocol instead of sending abort back.

- It wastes resources (especially with multiple netns), and SCTP module
  can't be unloaded once it's loaded.

...

In short, it's really inappropriate to have these family and proto
modules loaded unexpectedly when just doing debugging with inet_diag.

This patch is to introduce sock_load_diag_module() where it loads
the _diag module only when it's corresponding family or proto has
been already registered.

Note that we can't just load _diag module without the family or
proto loaded, as some symbols used in _diag module are from the
family or proto module.

v1->v2:
  - move inet proto check to inet_diag to avoid a compiling err.
v2->v3:
  - define sock_load_diag_module in sock.c and export one symbol
    only.
  - improve the changelog.
Reported-by: NSabrina Dubroca <sd@queasysnail.net>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: NPhil Sutter <phil@nwl.cc>
Acked-by: NSabrina Dubroca <sd@queasysnail.net>
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      bf2ae2e4
  21. 10 3月, 2018 1 次提交
    • E
      net: do not create fallback tunnels for non-default namespaces · 79134e6c
      由 Eric Dumazet 提交于 
      fallback tunnels (like tunl0, gre0, gretap0, erspan0, sit0,
ip6tnl0, ip6gre0) are automatically created when the corresponding
module is loaded.

These tunnels are also automatically created when a new network
namespace is created, at a great cost.

In many cases, netns are used for isolation purposes, and these
extra network devices are a waste of resources. We are using
thousands of netns per host, and hit the netns creation/delete
bottleneck a lot. (Many thanks to Kirill for recent work on this)

Add a new sysctl so that we can opt-out from this automatic creation.

Note that these tunnels are still created for the initial namespace,
to be the least intrusive for typical setups.

Tested:
lpk43:~# cat add_del_unshare.sh
for i in `seq 1 40`
do
 (for j in `seq 1 100` ; do  unshare -n /bin/true >/dev/null ; done) &
done
wait

lpk43:~# echo 0 >/proc/sys/net/core/fb_tunnels_only_for_init_net
lpk43:~# time ./add_del_unshare.sh

real	0m37.521s
user	0m0.886s
sys	7m7.084s
lpk43:~# echo 1 >/proc/sys/net/core/fb_tunnels_only_for_init_net
lpk43:~# time ./add_del_unshare.sh

real	0m4.761s
user	0m0.851s
sys	1m8.343s
lpk43:~#
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      79134e6c
  23. 09 3月, 2018 6 次提交
  25. 08 3月, 2018 2 次提交
  27. 07 3月, 2018 1 次提交