netdev - i40e: Fix preempt count leak in napi poll tracepoint

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Message-ID: <87v7g8zv2o.ffs@tglx>
Date: Sat, 07 Feb 2026 11:50:23 +0100
From: Thomas Gleixner <tglx@...nel.org>
To: intel-wired-lan@...ts.osuosl.org
Cc: Tony Nguyen <anthony.l.nguyen@...el.com>, Przemek Kitszel
 <przemyslaw.kitszel@...el.com>, netdev@...r.kernel.org
Subject: i40e: Fix preempt count leak in napi poll tracepoint

Using get_cpu() in the tracepoint assignment causes an obvious preempt
count leak because nothing invokes put_cpu() to undo it:

  softirq: huh, entered softirq 3 NET_RX with preempt_count 00000100, exited with 00000101?

This clearly has seen a lot of testing in the last 3+ years...

Use smp_processor_id() instead.

Fixes: 6d4d584a7ea8 ("i40e: Add i40e_napi_poll tracepoint")
Signed-off-by: Thomas Gleixner <tglx@...nel.org>
Cc: Tony Nguyen <anthony.l.nguyen@...el.com>
Cc: Przemek Kitszel <przemyslaw.kitszel@...el.com>
Cc: intel-wired-lan@...ts.osuosl.org
Cc: netdev@...r.kernel.org
---
 drivers/net/ethernet/intel/i40e/i40e_trace.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/ethernet/intel/i40e/i40e_trace.h
+++ b/drivers/net/ethernet/intel/i40e/i40e_trace.h
@@ -88,7 +88,7 @@ TRACE_EVENT(i40e_napi_poll,
 		__entry->rx_clean_complete = rx_clean_complete;
 		__entry->tx_clean_complete = tx_clean_complete;
 		__entry->irq_num = q->irq_num;
-		__entry->curr_cpu = get_cpu();
+		__entry->curr_cpu = smp_processor_id();
 		__assign_str(qname);
 		__assign_str(dev_name);
 		__assign_bitmask(irq_affinity, cpumask_bits(&q->affinity_mask),