diff options
| author | Kuniyuki Iwashima <kuniyu@google.com> | 2026-03-01 01:17:31 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-03-03 05:49:41 +0300 |
| commit | 4480d5fa1f6ebe7dfc546e14371d63c8b915a82d (patch) | |
| tree | ed85b16823337b289f164b952766e61b89be6d87 /net | |
| parent | 1c36d186a0c81f3b55b2722736163233b05f8756 (diff) | |
| download | linux-4480d5fa1f6ebe7dfc546e14371d63c8b915a82d.tar.xz | |
ipmr/ip6mr: Convert net->ipv[46].ipmr_seq to atomic_t.
We will no longer hold RTNL for ipmr_mfc_add() and ipmr_mfc_delete().
MFC entry can be loosely connected with VIF by its index for
mrt->vif_table[] (stored in mfc_parent), but the two tables are
not synchronised. i.e. Even if VIF 1 is removed, MFC for VIF 1
is not automatically removed.
The only field that the MFC/VIF interfaces share is
net->ipv[46].ipmr_seq, which is protected by RTNL.
Adding a new mutex for both just to protect a single field is overkill.
Let's convert the field to atomic_t.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260228221800.1082070-14-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/ipmr.c | 4 | ||||
| -rw-r--r-- | net/ipv6/ip6mr.c | 4 |
2 files changed, 4 insertions, 4 deletions
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c index 07f2d4f8dcbe..6ec73796d84d 100644 --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -3226,7 +3226,7 @@ static const struct net_protocol pim_protocol = { static unsigned int ipmr_seq_read(const struct net *net) { - return READ_ONCE(net->ipv4.ipmr_seq) + ipmr_rules_seq_read(net); + return atomic_read(&net->ipv4.ipmr_seq) + ipmr_rules_seq_read(net); } static int ipmr_dump(struct net *net, struct notifier_block *nb, @@ -3247,7 +3247,7 @@ static int __net_init ipmr_notifier_init(struct net *net) { struct fib_notifier_ops *ops; - net->ipv4.ipmr_seq = 0; + atomic_set(&net->ipv4.ipmr_seq, 0); ops = fib_notifier_ops_register(&ipmr_notifier_ops_template, net); if (IS_ERR(ops)) diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c index e047a4680ab0..85010ff21c98 100644 --- a/net/ipv6/ip6mr.c +++ b/net/ipv6/ip6mr.c @@ -1280,7 +1280,7 @@ static int ip6mr_device_event(struct notifier_block *this, static unsigned int ip6mr_seq_read(const struct net *net) { - return READ_ONCE(net->ipv6.ipmr_seq) + ip6mr_rules_seq_read(net); + return atomic_read(&net->ipv6.ipmr_seq) + ip6mr_rules_seq_read(net); } static int ip6mr_dump(struct net *net, struct notifier_block *nb, @@ -1305,7 +1305,7 @@ static int __net_init ip6mr_notifier_init(struct net *net) { struct fib_notifier_ops *ops; - net->ipv6.ipmr_seq = 0; + atomic_set(&net->ipv6.ipmr_seq, 0); ops = fib_notifier_ops_register(&ip6mr_notifier_ops_template, net); if (IS_ERR(ops)) |