e1000_request_msix() requests the RX, TX, and other-cause interrupt
handlers sequentially. If a later request_irq() fails, the function
returns without releasing handlers that were registered earlier. The
caller then disables MSI-X and falls back to MSI or legacy interrupts,
leaving those handlers registered against disabled MSI-X vectors.
Free all handlers registered before the failing request in reverse order
before returning the error. The failed vector is not freed, and the
existing fallback path can then disable MSI-X without retaining stale
handlers.
A QEMU e1000e test with deterministic failure injection at the third
request_irq() reproduced a residual IRQ entry and warning on the
unfixed kernel. The fixed kernel reached the same fallback without the
residual entry. The injection is deliberate and does not claim that a
third request_irq() failure occurs spontaneously during normal operation.
Fixes: 4662e82b2cb4 ("e1000e: add support for new 82574L part")
Cc: [email protected]
Assisted-by: LLM Codex
Signed-off-by: Runyu Xiao <[email protected]>
---
drivers/net/ethernet/intel/e1000e/netdev.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c
b/drivers/net/ethernet/intel/e1000e/netdev.c
index 844f31ab37ad4..f55aec340342b 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -2139,7 +2139,7 @@ static int e1000_request_msix(struct e1000_adapter
*adapter)
e1000_intr_msix_tx, 0, adapter->tx_ring->name,
netdev);
if (err)
- return err;
+ goto err_irq;
adapter->tx_ring->itr_register = adapter->hw.hw_addr +
E1000_EITR_82574(vector);
adapter->tx_ring->itr_val = adapter->itr;
@@ -2148,11 +2148,16 @@ static int e1000_request_msix(struct e1000_adapter
*adapter)
err = request_irq(adapter->msix_entries[vector].vector,
e1000_msix_other, 0, netdev->name, netdev);
if (err)
- return err;
+ goto err_irq;
e1000_configure_msix(adapter);
return 0;
+
+err_irq:
+ while (vector)
+ free_irq(adapter->msix_entries[--vector].vector, netdev);
+ return err;
}
/**
--
2.34.1
