[PATCH net v2] iavf: Detach device during reset task
From: Ivan Vecera <ivecera@redhat.com>
Date: 2022-08-29 16:31:19
Subsystem:
intel ethernet drivers, networking drivers, the rest · Maintainers:
Tony Nguyen, Przemek Kitszel, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
iavf_reset_task() takes crit_lock at the beginning and holds
it during whole call. The function subsequently calls
iavf_init_interrupt_scheme() that grabs RTNL. Problem occurs
when userspace initiates during the reset task any ndo callback
that runs under RTNL like iavf_open() because some of that
functions tries to take crit_lock. This leads to classic A-B B-A
deadlock scenario.
To resolve this situation the device should be detached in
iavf_reset_task() prior taking crit_lock to avoid subsequent
ndos running under RTNL and reattach the device at the end.
Fixes: 62fe2a865e6d ("i40evf: add missing rtnl_lock() around i40evf_set_interrupt_capability")
Cc: Jacob Keller <jacob.e.keller@intel.com>
Cc: Patryk Piotrowski <redacted>
Cc: SlawomirX Laba <redacted>
Tested-by: Vitaly Grinberg <redacted>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
---
drivers/net/ethernet/intel/iavf/iavf_main.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c
index f39440ad5c50..10aa99dfdcdb 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_main.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_main.c@@ -2877,6 +2877,11 @@ static void iavf_reset_task(struct work_struct *work) int i = 0, err; bool running; + /* Detach interface to avoid subsequent NDO callbacks */ + rtnl_lock(); + netif_device_detach(netdev); + rtnl_unlock(); + /* When device is being removed it doesn't make sense to run the reset * task, just return in such a case. */
@@ -2884,7 +2889,7 @@ static void iavf_reset_task(struct work_struct *work) if (adapter->state != __IAVF_REMOVE) queue_work(iavf_wq, &adapter->reset_task); - return; + goto reset_finish; } while (!mutex_trylock(&adapter->client_lock))
@@ -2954,7 +2959,6 @@ static void iavf_reset_task(struct work_struct *work) if (running) { netif_carrier_off(netdev); - netif_tx_stop_all_queues(netdev); adapter->link_up = false; iavf_napi_disable_all(adapter); }
@@ -3084,7 +3088,7 @@ static void iavf_reset_task(struct work_struct *work) mutex_unlock(&adapter->client_lock); mutex_unlock(&adapter->crit_lock); - return; + goto reset_finish; reset_err: if (running) { set_bit(__IAVF_VSI_DOWN, adapter->vsi.state);
@@ -3095,6 +3099,10 @@ static void iavf_reset_task(struct work_struct *work) mutex_unlock(&adapter->client_lock); mutex_unlock(&adapter->crit_lock); dev_err(&adapter->pdev->dev, "failed to allocate resources during reinit\n"); +reset_finish: + rtnl_lock(); + netif_device_attach(netdev); + rtnl_unlock(); } /**
--
2.35.1