When mana_per_port_queue_reset_work_handler() runs after a previous
detach succeeded but attach failed, the port is left in a detached
state with apc->tx_qp and apc->rxqs already freed. Calling
mana_detach() again unconditionally leads to NULL pointer dereferences
during queue teardown.
Add an early exit in mana_detach() when the port is already in
detached state (!netif_device_present) for non-close callers, making
it safe to call idempotently. This allows the queue reset handler and
other recovery paths to simply retry mana_attach() without redundant
teardown.
Fixes: 3b194343c250 ("net: mana: Implement ndo_tx_timeout and serialize queue
resets per port.")
Reviewed-by: Haiyang Zhang <[email protected]>
Signed-off-by: Dipayaan Roy <[email protected]>
---
drivers/net/ethernet/microsoft/mana/mana_en.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c
b/drivers/net/ethernet/microsoft/mana/mana_en.c
index 0582803907a8..1e1ad2795c3c 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
@@ -3350,6 +3350,12 @@ int mana_detach(struct net_device *ndev, bool from_close)
ASSERT_RTNL();
+ /* If already detached (indicates detach succeeded but attach failed
+ * previously). Now skip mana detach and just retry mana_attach.
+ */
+ if (!from_close && !netif_device_present(ndev))
+ return 0;
+
apc->port_st_save = apc->port_is_up;
apc->port_is_up = false;
--
2.43.0
