Commit 407e0efd authored by Eric Dumazet's avatar Eric Dumazet Committed by Jakub Kicinski
Browse files

idpf: fix idpf_vport_splitq_napi_poll() 



idpf_vport_splitq_napi_poll() can incorrectly return @budget
after napi_complete_done() has been called.

This violates NAPI rules, because after napi_complete_done(),
current thread lost napi ownership.

Move the test against POLL_MODE before the napi_complete_done().

Fixes: c2d548ca ("idpf: add TX splitq napi poll support")
Reported-by: default avatarPeter Newman <peternewman@google.com>
Closes: https://lore.kernel.org/netdev/20250520121908.1805732-1-edumazet@google.com/T/#u


Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Cc: Joshua Hay <joshua.a.hay@intel.com>
Cc: Alan Brady <alan.brady@intel.com>
Cc: Madhu Chittim <madhu.chittim@intel.com>
Cc: Phani Burra <phani.r.burra@intel.com>
Cc: Pavan Kumar Linga <pavan.kumar.linga@intel.com>
Link: https://patch.msgid.link/20250520124030.1983936-1-edumazet@google.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent d83ec0b2

drivers/net/ethernet/intel/idpf/idpf_txrx.c

+9 −9
Original line number Diff line number Diff line
@@ -4025,6 +4025,14 @@ static int idpf_vport_splitq_napi_poll(struct napi_struct *napi, int budget) 
		return budget;

	}



	/* Switch to poll mode in the tear-down path after sending disable

	 * queues virtchnl message, as the interrupts will be disabled after

	 * that.

	 */

	if (unlikely(q_vector->num_txq && idpf_queue_has(POLL_MODE,

							 q_vector->tx[0])))

		return budget;



	work_done = min_t(int, work_done, budget - 1);



	/* Exit the polling mode, but don't re-enable interrupts if stack might
@@ -4035,14 +4043,6 @@ static int idpf_vport_splitq_napi_poll(struct napi_struct *napi, int budget) 
	else

		idpf_vport_intr_set_wb_on_itr(q_vector);



	/* Switch to poll mode in the tear-down path after sending disable

	 * queues virtchnl message, as the interrupts will be disabled after

	 * that

	 */

	if (unlikely(q_vector->num_txq && idpf_queue_has(POLL_MODE,

							 q_vector->tx[0])))

		return budget;

	else

	return work_done;

}