In a CVM environment, hardware responses cannot be trusted. The GDMA_QUERY_MAX_RESOURCES command returns resource limits used to determine the maximum number of queues.
In mana_gd_query_max_resources(), gc->max_num_queues is initialized from num_online_cpus() and successively clamped by the hardware-reported max_eq, max_cq, max_sq, max_rq, and num_msix_usable values. If any of these hardware values is zero, gc->max_num_queues becomes zero and the function returns success. This leads to a confusing failure later when alloc_etherdev_mq() is called with zero queues, returning NULL and producing a misleading -ENOMEM error. Add an explicit zero check for gc->max_num_queues after all clamping steps and return -ENOSPC for a clear early failure, consistent with the existing gc->num_msix_usable <= 1 guard. Signed-off-by: Erni Sri Satya Vennela <[email protected]> --- Changes in v2: * Rebase to latest main. --- drivers/net/ethernet/microsoft/mana/gdma_main.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/ethernet/microsoft/mana/gdma_main.c b/drivers/net/ethernet/microsoft/mana/gdma_main.c index 098fbda0d128..f3316e929175 100644 --- a/drivers/net/ethernet/microsoft/mana/gdma_main.c +++ b/drivers/net/ethernet/microsoft/mana/gdma_main.c @@ -194,6 +194,9 @@ static int mana_gd_query_max_resources(struct pci_dev *pdev) if (gc->max_num_queues > gc->num_msix_usable - 1) gc->max_num_queues = gc->num_msix_usable - 1; + if (gc->max_num_queues == 0) + return -ENOSPC; + return 0; } -- 2.34.1
