i40e: add ability to reset VF for Tx and Rx MDD events

Implement "mdd-auto-reset-vf" priv-flag to handle Tx and Rx MDD events for VFs.
This flag is also used in other network adapters like ICE.

Usage:
- "on"  - The problematic VF will be automatically reset
	  if a malformed descriptor is detected.
- "off" - The problematic VF will be disabled.

In cases where a VF sends malformed packets classified as malicious, it can
cause the Tx queue to freeze, rendering it unusable for several minutes. When
an MDD event occurs, this new implementation allows for a graceful VF reset to
quickly restore operational state.

Currently, VF queues are disabled if an MDD event occurs. This patch adds the
ability to reset the VF if a Tx or Rx MDD event occurs. It also includes MDD
event logging throttling to avoid dmesg pollution and unifies the format of
Tx and Rx MDD messages.

Note: Standard message rate limiting functions like dev_info_ratelimited()
do not meet our requirements. Custom rate limiting is implemented,
please see the code for details.

Co-developed-by: Jan Sokolowski <jan.sokolowski@intel.com>
Signed-off-by: Jan Sokolowski <jan.sokolowski@intel.com>
Co-developed-by: Padraig J Connolly <padraig.j.connolly@intel.com>
Signed-off-by: Padraig J Connolly <padraig.j.connolly@intel.com>
Signed-off-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Reviewed-by: Michal Schmidt <mschmidt@redhat.com>
Tested-by: Rafal Romanowski <rafal.romanowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Link: https://patch.msgid.link/20250106221929.956999-13-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index ce63a7cfe955..c67963bfe14e 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -88,6 +88,7 @@ enum i40e_state {
 	__I40E_SERVICE_SCHED,
 	__I40E_ADMINQ_EVENT_PENDING,
 	__I40E_MDD_EVENT_PENDING,
+	__I40E_MDD_VF_PRINT_PENDING,
 	__I40E_VFLR_EVENT_PENDING,
 	__I40E_RESET_RECOVERY_PENDING,
 	__I40E_TIMEOUT_RECOVERY_PENDING,
@@ -191,6 +192,7 @@ enum i40e_pf_flags {
 	 */
 	I40E_FLAG_TOTAL_PORT_SHUTDOWN_ENA,
 	I40E_FLAG_VF_VLAN_PRUNING_ENA,
+	I40E_FLAG_MDD_AUTO_RESET_VF,
 	I40E_PF_FLAGS_NBITS,		/* must be last */
 };
 
@@ -572,7 +574,7 @@ struct i40e_pf {
 	int num_alloc_vfs;	/* actual number of VFs allocated */
 	u32 vf_aq_requests;
 	u32 arq_overflows;	/* Not fatal, possibly indicative of problems */
-
+	struct ratelimit_state mdd_message_rate_limit;
 	/* DCBx/DCBNL capability for PF that indicates
 	 * whether DCBx is managed by firmware or host
 	 * based agent (LLDPAD). Also, indicates what