net/mlx5: Lag, avoid LAG and representor lock cycles

The LAG shared-FDB and multiport E-Switch transitions rescan auxiliary
devices and reload IB representors while holding ldev->lock. Driver
bind/unbind paths may register or unregister E-Switch representor ops, and
representor load paths may enter LAG code, so holding ldev->lock across
those calls creates lock-order cycles with the E-Switch representor lock.

Keep the devcom component locked for the transition, but drop ldev->lock
before rescanning auxiliary devices or reloading IB representors. Mark the
LAG transition as in progress while the lock is dropped and assert the
devcom lock where the helper relies on it. This preserves LAG serialization
while avoiding ldev->lock nesting under E-Switch representor registration.

Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/20260503202726.266415-5-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Mark Bloch 2026-05-03 23:27:23 +03:00 • committed by Jakub Kicinski
commit 63ec6c69e6
5 changed files with 134 additions and 34 deletions