| Message ID | 20240412122538.51-1-lizheng043@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | neighbour: guarantee the localhost connections be established successfully even the ARP table is full | expand |
On Fri, 12 Apr 2024 20:25:38 +0800 Zheng Li wrote: > Inter-process communication on localhost should be established successfully even the ARP table is full, > many processes on server machine use the localhost to communicate such as command-line interface (CLI), > servers hope all CLI commands can be executed successfully even the arp table is full. > Right now CLI commands got timeout when the arp table is full. > Set the parameter of exempt_from_gc to be true for LOOPBACK net device to > keep localhost neigh in arp table, not removed by gc. > > the steps of reproduced: > server with "gc_thresh3 = 1024" setting, ping server from more than 1024 IPv4 addresses, > run "ssh localhost" on console interface, then the command will get timeout. Please repost this and CC appropriate maintainers. scripts/get_maintainer doesn't bite.
On Fri, Apr 12, 2024 at 08:25:38PM +0800, Zheng Li wrote: > From: Zheng Li <James.Z.Li@Dell.com> > > Inter-process communication on localhost should be established successfully even the ARP table is full, > many processes on server machine use the localhost to communicate such as command-line interface (CLI), > servers hope all CLI commands can be executed successfully even the arp table is full. > Right now CLI commands got timeout when the arp table is full. > Set the parameter of exempt_from_gc to be true for LOOPBACK net device to > keep localhost neigh in arp table, not removed by gc. > > the steps of reproduced: > server with "gc_thresh3 = 1024" setting, ping server from more than 1024 IPv4 addresses, > run "ssh localhost" on console interface, then the command will get timeout. > > Signed-off-by: Zheng Li <James.Z.Li@Dell.com> > --- > net/core/neighbour.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/net/core/neighbour.c b/net/core/neighbour.c > index 552719c3bbc3..d96dee3d4af6 100644 > --- a/net/core/neighbour.c > +++ b/net/core/neighbour.c > @@ -734,7 +734,10 @@ ___neigh_create(struct neigh_table *tbl, const void *pkey, > struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey, > struct net_device *dev, bool want_ref) > { > - return ___neigh_create(tbl, pkey, dev, 0, false, want_ref); > + if (dev->flags & IFF_LOOPBACK) > + return ___neigh_create(tbl, pkey, dev, 0, true, want_ref); > + else > + return ___neigh_create(tbl, pkey, dev, 0, false, want_ref); > } > EXPORT_SYMBOL(__neigh_create); Hi James, I'm not commenting on the merits of your patch - I'm sure the maintainers will do so when you repost as Jakub has suggested. But wile looking at this it seemed to me that the following might be a cleaner way to express your change. struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey, struct net_device *dev, bool want_ref) { bool exempt_from_gc = !!(dev->flags & IFF_LOOPBACK); return ___neigh_create(tbl, pkey, dev, 0, exempt_from_gc, want_ref); }
diff --git a/net/core/neighbour.c b/net/core/neighbour.c index 552719c3bbc3..d96dee3d4af6 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -734,7 +734,10 @@ ___neigh_create(struct neigh_table *tbl, const void *pkey, struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey, struct net_device *dev, bool want_ref) { - return ___neigh_create(tbl, pkey, dev, 0, false, want_ref); + if (dev->flags & IFF_LOOPBACK) + return ___neigh_create(tbl, pkey, dev, 0, true, want_ref); + else + return ___neigh_create(tbl, pkey, dev, 0, false, want_ref); } EXPORT_SYMBOL(__neigh_create);