linux.git/drivers/net/vxlan, branch v6.16

treewide, timers: Rename from_timer() to timer_container_of()

2025-06-08T07:07:37+00:00

Move this API to the canonical timer_*() namespace.

[ tglx: Redone against pre rc1 ]

Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner 
Link: https://lore.kernel.org/all/aB2X0jCKQO56WdMt@gmail.com

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2025-04-24T18:20:52+00:00

Cross-merge networking fixes after downstream PR (net-6.15-rc4).

This pull includes wireless and a fix to vxlan which isn't
in Linus's tree just yet. The latter creates with a silent conflict
/ build breakage, so merging it now to avoid causing problems.

drivers/net/vxlan/vxlan_vnifilter.c
  094adad91310 ("vxlan: Use a single lock to protect the FDB table")
  087a9eb9e597 ("vxlan: vnifilter: Fix unlocked deletion of default FDB entry")
https://lore.kernel.org/20250423145131.513029-1-idosch@nvidia.com

No "normal" conflicts, or adjacent changes.

Signed-off-by: Jakub Kicinski

vxlan: vnifilter: Fix unlocked deletion of default FDB entry

2025-04-24T18:11:24+00:00

When a VNI is deleted from a VXLAN device in 'vnifilter' mode, the FDB
entry associated with the default remote (assuming one was configured)
is deleted without holding the hash lock. This is wrong and will result
in a warning [1] being generated by the lockdep annotation that was
added by commit ebe642067455 ("vxlan: Create wrappers for FDB lookup").

Reproducer:

 # ip link add vx0 up type vxlan dstport 4789 external vnifilter local 192.0.2.1
 # bridge vni add vni 10010 remote 198.51.100.1 dev vx0
 # bridge vni del vni 10010 dev vx0

Fix by acquiring the hash lock before the deletion and releasing it
afterwards. Blame the original commit that introduced the issue rather
than the one that exposed it.

[1]
WARNING: CPU: 3 PID: 392 at drivers/net/vxlan/vxlan_core.c:417 vxlan_find_mac+0x17f/0x1a0
[...]
RIP: 0010:vxlan_find_mac+0x17f/0x1a0
[...]
Call Trace:
 
 __vxlan_fdb_delete+0xbe/0x560
 vxlan_vni_delete_group+0x2ba/0x940
 vxlan_vni_del.isra.0+0x15f/0x580
 vxlan_process_vni_filter+0x38b/0x7b0
 vxlan_vnifilter_process+0x3bb/0x510
 rtnetlink_rcv_msg+0x2f7/0xb70
 netlink_rcv_skb+0x131/0x360
 netlink_unicast+0x426/0x710
 netlink_sendmsg+0x75a/0xc20
 __sock_sendmsg+0xc1/0x150
 ____sys_sendmsg+0x5aa/0x7b0
 ___sys_sendmsg+0xfc/0x180
 __sys_sendmsg+0x121/0x1b0
 do_syscall_64+0xbb/0x1d0
 entry_SYSCALL_64_after_hwframe+0x4b/0x53

Fixes: f9c4bb0b245c ("vxlan: vni filtering support on collect metadata device")
Signed-off-by: Ido Schimmel 
Reviewed-by: Nikolay Aleksandrov 
Link: https://patch.msgid.link/20250423145131.513029-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski

vxlan: Convert FDB table to rhashtable

2025-04-22T09:11:16+00:00

FDB entries are currently stored in a hash table with a fixed number of
buckets (256), resulting in performance degradation as the number of
entries grows. Solve this by converting the driver to use rhashtable
which maintains more or less constant performance regardless of the
number of entries.

Measured transmitted packets per second using a single pktgen thread
with varying number of entries when the transmitted packet always hits
the default entry (worst case):

Number of entries | Improvement
------------------|------------
1k                | +1.12%
4k                | +9.22%
16k               | +55%
64k               | +585%
256k              | +2460%

In addition, the change reduces the size of the VXLAN device structure
from 2584 bytes to 672 bytes.

Reviewed-by: Petr Machata 
Signed-off-by: Ido Schimmel 
Link: https://patch.msgid.link/20250415121143.345227-16-idosch@nvidia.com
Reviewed-by: Nikolay Aleksandrov 
Signed-off-by: Paolo Abeni

vxlan: Introduce FDB key structure

2025-04-22T09:11:16+00:00

In preparation for converting the FDB table to rhashtable, introduce a
key structure that includes the MAC address and source VNI.

No functional changes intended.

Reviewed-by: Petr Machata 
Signed-off-by: Ido Schimmel 
Link: https://patch.msgid.link/20250415121143.345227-15-idosch@nvidia.com
Reviewed-by: Nikolay Aleksandrov 
Signed-off-by: Paolo Abeni

vxlan: Do not treat dst cache initialization errors as fatal

2025-04-22T09:11:16+00:00

FDB entries are allocated in an atomic context as they can be added from
the data path when learning is enabled.

After converting the FDB hash table to rhashtable, the insertion rate
will be much higher (*) which will entail a much higher rate of per-CPU
allocations via dst_cache_init().

When adding a large number of entries (e.g., 256k) in a batch, a small
percentage (< 0.02%) of these per-CPU allocations will fail [1]. This
does not happen with the current code since the insertion rate is low
enough to give the per-CPU allocator a chance to asynchronously create
new chunks of per-CPU memory.

Given that:

a. Only a small percentage of these per-CPU allocations fail.

b. The scenario where this happens might not be the most realistic one.

c. The driver can work correctly without dst caches. The dst_cache_*()
APIs first check that the dst cache was properly initialized.

d. The dst caches are not always used (e.g., 'tos inherit').

It seems reasonable to not treat these allocation failures as fatal.

Therefore, do not bail when dst_cache_init() fails and suppress warnings
by specifying '__GFP_NOWARN'.

[1] percpu: allocation failed, size=40 align=8 atomic=1, atomic alloc failed, no space left

(*) 97% reduction in average latency of vxlan_fdb_update() when adding
256k entries in a batch.

Reviewed-by: Petr Machata 
Signed-off-by: Ido Schimmel 
Link: https://patch.msgid.link/20250415121143.345227-14-idosch@nvidia.com
Reviewed-by: Nikolay Aleksandrov 
Signed-off-by: Paolo Abeni

vxlan: Create wrappers for FDB lookup

2025-04-22T09:11:16+00:00

__vxlan_find_mac() is called from both the data path (e.g., during
learning) and the control path (e.g., when replacing an entry). The
function is missing lockdep annotations to make sure that the FDB hash
lock is held during FDB updates.

Rename __vxlan_find_mac() to vxlan_find_mac_rcu() to reflect the fact
that it should be called from an RCU read-side critical section and call
it from vxlan_find_mac() which checks that the FDB hash lock is held.
Change callers to invoke the appropriate function.

Reviewed-by: Petr Machata 
Signed-off-by: Ido Schimmel 
Link: https://patch.msgid.link/20250415121143.345227-13-idosch@nvidia.com
Reviewed-by: Nikolay Aleksandrov 
Signed-off-by: Paolo Abeni

vxlan: Rename FDB Tx lookup function

2025-04-22T09:11:16+00:00

vxlan_find_mac() is only expected to be called from the Tx path as it
updates the 'used' timestamp. Rename it to vxlan_find_mac_tx() to
reflect that and to avoid incorrect updates of this timestamp like those
addressed by commit 9722f834fe9a ("vxlan: Avoid unnecessary updates to
FDB 'used' time").

No functional changes intended.

Reviewed-by: Petr Machata 
Signed-off-by: Ido Schimmel 
Link: https://patch.msgid.link/20250415121143.345227-12-idosch@nvidia.com
Reviewed-by: Nikolay Aleksandrov 
Signed-off-by: Paolo Abeni

vxlan: Convert FDB flushing to RCU

2025-04-22T09:11:16+00:00

Instead of holding the FDB hash lock when traversing the FDB linked list
during flushing, use RCU and only acquire the lock for entries that need
to be flushed.

Reviewed-by: Petr Machata 
Signed-off-by: Ido Schimmel 
Link: https://patch.msgid.link/20250415121143.345227-11-idosch@nvidia.com
Reviewed-by: Nikolay Aleksandrov 
Signed-off-by: Paolo Abeni

vxlan: Convert FDB garbage collection to RCU

2025-04-22T09:11:15+00:00

Instead of holding the FDB hash lock when traversing the FDB linked list
during garbage collection, use RCU and only acquire the lock for entries
that need to be removed (aged out).

Avoid races by using hlist_unhashed() to check that the entry has not
been removed from the list by another thread.

Note that vxlan_fdb_destroy() uses hlist_del_init_rcu() to remove an
entry from the list which should cause list_unhashed() to return true.

Reviewed-by: Petr Machata 
Signed-off-by: Ido Schimmel 
Link: https://patch.msgid.link/20250415121143.345227-10-idosch@nvidia.com
Reviewed-by: Nikolay Aleksandrov 
Signed-off-by: Paolo Abeni