Re: [PATCH] wifi: ath11k: fix warning when unbinding

From: Rameshkumar Sundaram

Date: Thu May 14 2026 - 02:56:17 EST


On 5/14/2026 11:48 AM, Jose Ignacio Tornos Martinez wrote:
Hello Rameshkumar,

I agree that setting tx_status to NULL makes ath11k_dp_free() more
defensive, and it matches the ath12k fix.
Ok, I agree too.

However, i am still wondering how the second ath11k_dp_free() is reached
if ATH11K_FLAG_QMI_FAIL is set.

In ath11k_pci_remove(), when ATH11K_FLAG_QMI_FAIL is set, we take the
qmi_fail path and skip ath11k_core_deinit(). So the normal remove path:

ath11k_pci_remove()
ath11k_core_deinit()
ath11k_core_soc_destroy()
ath11k_dp_free()

should not run.

So if the double free is still reproducible with QMI_FAIL set (with the
change i proposed), either the flag is not actually set in this failure
case, or there is another path calling ath11k_dp_free() ?
Let me try to clarify the issue more.
There are two error actions:
- First the previous error. I reproduce the situation as I commented: running
in a VM the default upstream kernel (with this card using PCI passthrough),
since this is always failing. Let me show the logs in this situation:
[ 15.906564] ath11k_pci 0000:07:00.0: BAR 0 [mem 0xfdc00000-0xfddfffff 64bit]: assigned
[ 15.926520] ath11k_pci 0000:07:00.0: MSI vectors: 32
[ 15.928572] ath11k_pci 0000:07:00.0: wcn6855 hw2.0
[ 16.984192] ath11k_pci 0000:07:00.0: chip_id 0x2 chip_family 0xb board_id 0xff soc_id 0x400c0200
[ 16.984351] ath11k_pci 0000:07:00.0: fw_version 0x11088c35 fw_build_timestamp 2024-04-17 08:34 fw_build_id WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41
[ 18.186971] ath11k_pci 0000:07:00.0: failed to receive control response completion, polling..
[ 19.211036] ath11k_pci 0000:07:00.0: Service connect timeout
[ 19.211815] ath11k_pci 0000:07:00.0: failed to connect to HTT: -110
[ 19.214181] ath11k_pci 0000:07:00.0: failed to start core: -110
[ 19.531989] ath11k_pci 0000:07:00.0: firmware crashed: MHI_CB_EE_RDDM
[ 19.532930] ath11k_pci 0000:07:00.0: ignore reset dev flags 0xc000
[ 29.259157] ath11k_pci 0000:07:00.0: failed to wait wlan mode request (mode 4): -110
[ 29.259229] ath11k_pci 0000:07:00.0: qmi failed to send wlan mode off: -110
- Second after this, I commanded the unbinded (ath11_pci) and I get the
warning. Let extend here the stack trace:
[ 24.238198] ? free_large_kmalloc+0x57/0x90
[ 24.238199] ? report_bug+0x16b/0x180
[ 24.238210] ? handle_bug+0x3c/0x70
[ 24.238218] ? exc_invalid_op+0x14/0x70
[ 24.238218] ? asm_exc_invalid_op+0x16/0x20
[ 24.238224] ? free_large_kmalloc+0x57/0x90
[ 24.238227] ath11k_dp_free+0x99/0xb0 [ath11k]
[ 24.238275] ath11k_core_deinit+0x12b/0x1a0 [ath11k]
[ 24.238287] ath11k_pci_remove+0x7b/0x120 [ath11k_pci]
[ 24.238294] pci_device_remove+0x3e/0xb0
[ 24.238304] device_release_driver_internal+0x193/0x200
[ 24.238315] unbind_store+0x9d/0xb0
[ 24.238320] kernfs_fop_write_iter+0x13a/0x1d0
[ 24.238330] vfs_write+0x32e/0x470
[ 24.238335] ksys_write+0x5f/0xe0
[ 24.238336] do_syscall_64+0x5f/0xe0
Very easy to reproduce.



Thanks much for the logs, that makes sense. The timestamps explain why my earlier reasoning did not match the trace: unbind reaches ath11k_pci_remove() before ATH11K_FLAG_QMI_FAIL is set by the QMI event worker as it is held up on wlan mode off qmi transaction, so remove still takes the normal ath11k_core_deinit() path.


--
Ramesh