[PATCH 6.12.y] wifi: ath12k: Clear affinity hint before calling ath12k_pci_free_irq() in error path

[PATCH 6.12.y] wifi: ath12k: Clear affinity hint before calling ath12k_pci_free_irq() in error path

[jetlan9]

From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

[ Upstream commit b43b1e2c52db77c872bd60d30cdcc72c47df70c7 ]

If a shared IRQ is used by the driver due to platform limitation, then the
IRQ affinity hint is set right after the allocation of IRQ vectors in
ath12k_pci_msi_alloc(). This does no harm unless one of the functions
requesting the IRQ fails and attempt to free the IRQ.

This may end up with a warning from the IRQ core that is expecting the
affinity hint to be cleared before freeing the IRQ:

kernel/irq/manage.c:

	/* make sure affinity_hint is cleaned up */
	if (WARN_ON_ONCE(desc->affinity_hint))
		desc->affinity_hint = NULL;

So to fix this issue, clear the IRQ affinity hint before calling
ath12k_pci_free_irq() in the error path. The affinity will be cleared once
again further down the error path due to code organization, but that does
no harm.

Fixes: a3012f206d07 ("wifi: ath12k: set IRQ affinity to CPU0 in case of one MSI vector")
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Baochen Qiang <quic_bqiang@quicinc.com>
Link: https://patch.msgid.link/20250225053447.16824-3-manivannan.sadhasivam@linaro.org
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Signed-off-by: Wenshan Lan <jetlan9@163.com>
---
 drivers/net/wireless/ath/ath12k/pci.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/wireless/ath/ath12k/pci.c b/drivers/net/wireless/ath/ath12k/pci.c
index 45d537066345..9c35fbe52872 100644
--- a/drivers/net/wireless/ath/ath12k/pci.c
+++ b/drivers/net/wireless/ath/ath12k/pci.c
@@ -1503,6 +1503,8 @@ static int ath12k_pci_probe(struct pci_dev *pdev,
 	return 0;
 
 err_free_irq:
+	/* __free_irq() expects the caller to have cleared the affinity hint */
+	ath12k_pci_set_irq_affinity_hint(ab_pci, NULL);
 	ath12k_pci_free_irq(ab);
 
 err_ce_free:
-- 
2.34.1

Re: [PATCH 6.12.y] wifi: ath12k: Clear affinity hint before calling ath12k_pci_free_irq() in error path

[Sasha Levin]

[ Sasha's backport helper bot ]

Hi,

✅ All tests passed successfully. No issues detected.
No action required from the submitter.

The upstream commit SHA1 provided is correct: b43b1e2c52db77c872bd60d30cdcc72c47df70c7

WARNING: Author mismatch between patch and upstream commit:
Backport author: jetlan9@163.com
Commit author: Manivannan Sadhasivam<manivannan.sadhasivam@linaro.org>

Status in newer kernel trees:
6.15.y | Present (exact SHA1)

Note: The patch differs from the upstream commit:
---
1:  b43b1e2c52db7 ! 1:  eea26e883e126 wifi: ath12k: Clear affinity hint before calling ath12k_pci_free_irq() in error path
    @@ Metadata
      ## Commit message ##
         wifi: ath12k: Clear affinity hint before calling ath12k_pci_free_irq() in error path
     
    +    [ Upstream commit b43b1e2c52db77c872bd60d30cdcc72c47df70c7 ]
    +
         If a shared IRQ is used by the driver due to platform limitation, then the
         IRQ affinity hint is set right after the allocation of IRQ vectors in
         ath12k_pci_msi_alloc(). This does no harm unless one of the functions
    @@ Commit message
         Reviewed-by: Baochen Qiang <quic_bqiang@quicinc.com>
         Link: https://patch.msgid.link/20250225053447.16824-3-manivannan.sadhasivam@linaro.org
         Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
    +    Signed-off-by: Wenshan Lan <jetlan9@163.com>
     
      ## drivers/net/wireless/ath/ath12k/pci.c ##
     @@ drivers/net/wireless/ath/ath12k/pci.c: static int ath12k_pci_probe(struct pci_dev *pdev,
---

Results of testing on various branches:

| Branch                    | Patch Apply | Build Test |
|---------------------------|-------------|------------|
| stable/linux-6.12.y       |  Success    |  Success   |