If there is an error during some initialization related to firmware, the buffers dp->tx_ring[i].tx_status are released. However this is released again when the device is unbinded (ath12k_pci), and we get: WARNING: CPU: 0 PID: 2098 at mm/slub.c:4689 free_large_kmalloc+0x4d/0x80 Call Trace: free_large_kmalloc ath12k_dp_free ath12k_core_deinit ath12k_pci_remove ...
The issue is always reproducible from a VM because the MSI addressing initialization is failing.
In order to fix the issue, just set the buffers to NULL after releasing in order to avoid the double free.
cc: stable@vger.kernel.org Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices") Signed-off-by: Jose Ignacio Tornos Martinez jtornosm@redhat.com --- v3: - Remove unnecessary check to not free if buffer is NULL. - Trim backtrace. - Fix typos. v2: https://lore.kernel.org/linux-wireless/20241016123722.206899-1-jtornosm@redh... v1: https://lore.kernel.org/linux-wireless/20241010175102.207324-3-jtornosm@redh...
drivers/net/wireless/ath/ath12k/dp.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/ath/ath12k/dp.c b/drivers/net/wireless/ath/ath12k/dp.c index 789d430e4455..15061782a2df 100644 --- a/drivers/net/wireless/ath/ath12k/dp.c +++ b/drivers/net/wireless/ath/ath12k/dp.c @@ -1277,8 +1277,10 @@ void ath12k_dp_free(struct ath12k_base *ab)
ath12k_dp_rx_reo_cmd_list_cleanup(ab);
- for (i = 0; i < ab->hw_params->max_tx_ring; i++) + for (i = 0; i < ab->hw_params->max_tx_ring; i++) { kfree(dp->tx_ring[i].tx_status); + dp->tx_ring[i].tx_status = NULL; + }
ath12k_dp_rx_free(ab); /* Deinit any SOC level resource */