> -----Original Message----- > From: Tian Run <[email protected]> > Sent: Tuesday, September 15, 2026 12:11 PM > To: [email protected]; [email protected] > Cc: Nguyen, Anthony L <[email protected]>; Kitszel, Przemyslaw > <[email protected]>; Andrew Lunn <[email protected]>; > David S.Miller <[email protected]>; Eric Dumazet <[email protected]>; > Jakub Kicinski <[email protected]>; Paolo Abeni <[email protected]>; linux- > [email protected] > Subject: [PATCH net-next] i40e: fix VF queue mapping collision with PF queue 0 > > i40e_vsi_setup() limits the queue pairs of an SRIOV VSI to > pf->num_lan_msix and fills info.queue_mapping[] only for that many > entries, leaving the rest zeroed. i40e_vc_get_pf_queue_id() resolves such an > entry to absolute queue 0, which belongs to the PF itself. > > i40e_config_vsi_tx_queue() then overwrites the PF's queue 0 context with the > VF's ring and re-programs QTX_CTL(0) into VF mode. The PF's next transmit on > queue 0 wedges the queue: the device stops it, reports a Malicious Driver > Detection event without a valid event ID, sets both PF_MDET_TX and > VP_MDET_TX and the PF enters a NETDEV WATCHDOG / reset loop. > > alloc_queue_pairs is set to pf->num_vf_qps, so GET_VF_RESOURCES advertises > the full count and a VF with more online CPUs than the PF's num_lan_msix > (e.g. a > 4-CPU guest on a 3-CPU host) configures the extra queue pair and hits the > unprogrammed mapping entry. > > Clamp alloc_queue_pairs by num_lan_msix like i40e_vsi_setup() does, so the VF > is only offered queue pairs whose mapping was programmed. > > Fixes: 1563f2d2e012 ("i40e: Do not allow use more TC queue pairs than MSI-X > vectors exist") > Signed-off-by: Tian Run <[email protected]> > --- > drivers/net/ethernet/intel/i40e/i40e_main.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c > b/drivers/net/ethernet/intel/i40e/i40e_main.c > index abbc71e81..2934862da 100644 > --- a/drivers/net/ethernet/intel/i40e/i40e_main.c > +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c > @@ -11443,6 +11443,12 @@ static int i40e_set_num_rings_in_vsi(struct > i40e_vsi *vsi) > > case I40E_VSI_SRIOV: > vsi->alloc_queue_pairs = pf->num_vf_qps; > + /* i40e_vsi_setup() limits queue pairs to num_lan_msix; > + * keep alloc_queue_pairs consistent with that limit. > + */ > + if (test_bit(I40E_FLAG_MSIX_ENA, pf->flags)) > + vsi->alloc_queue_pairs = > + min_t(u16, pf->num_vf_qps, pf- > >num_lan_msix); > if (!vsi->num_tx_desc) > vsi->num_tx_desc = > ALIGN(I40E_DEFAULT_NUM_DESCRIPTORS, > > I40E_REQ_DESCRIPTOR_MULTIPLE); > -- > 2.43.0
Tested-by: Rafal Romanowski <[email protected]>
