On Thu, Apr 30, 2026 at 01:36:21AM -0700, Erni Sri Satya Vennela wrote: > 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; > } >
Reviewed-by: Shradha Gupta <[email protected]> > -- > 2.34.1
