[PATCH] wifi: ath12k: Prevent sending WMI commands to firmware during firmware crash

[Maharaja Kennadyrajan]

> -----Original Message-----
> From: Maharaja Kennadyrajan <maharaja.kennadyrajan at oss.qualcomm.com>
> Sent: Wednesday, April 16, 2025 7:32 AM
> To: ath12k at lists.infradead.org
> Cc: linux-wireless at vger.kernel.org; Maharaja Kennadyrajan
> <maharaja.kennadyrajan at oss.qualcomm.com>
> Subject: [PATCH] wifi: ath12k: Prevent sending WMI commands to firmware
> during firmware crash

Ignore this patch as tag is missing in the commit title. Will add this and send in next version.

> 
> WARNING: This email originated from outside of Qualcomm. Please be wary of
> any links or attachments, and do not enable macros.
> 
> Currently, we encounter the following kernel call trace when a firmware crash
> occurs. This happens because the host sends WMI commands to the firmware
> while it is in recovery, causing the commands to fail and resulting in the kernel call
> trace.
> 
> Set the ATH12K_FLAG_CRASH_FLUSH and ATH12K_FLAG_RECOVERY flags when
> the host driver receives the firmware crash notification from MHI. This prevents
> sending WMI commands to the firmware during recovery.
> 
> Call Trace:
>  <TASK>
>  dump_stack_lvl+0x75/0xc0
>  register_lock_class+0x6be/0x7a0
>  ? __lock_acquire+0x644/0x19a0
>  __lock_acquire+0x95/0x19a0
>  lock_acquire+0x265/0x310
>  ? ath12k_ce_send+0xa2/0x210 [ath12k]
>  ? find_held_lock+0x34/0xa0
>  ? ath12k_ce_send+0x56/0x210 [ath12k]
>  _raw_spin_lock_bh+0x33/0x70
>  ? ath12k_ce_send+0xa2/0x210 [ath12k]
>  ath12k_ce_send+0xa2/0x210 [ath12k]
>  ath12k_htc_send+0x178/0x390 [ath12k]
>  ath12k_wmi_cmd_send_nowait+0x76/0xa0 [ath12k]
>  ath12k_wmi_cmd_send+0x62/0x190 [ath12k]
>  ath12k_wmi_pdev_bss_chan_info_request+0x62/0xc0 [ath1
>  ath12k_mac_op_get_survey+0x2be/0x310 [ath12k]
>  ieee80211_dump_survey+0x99/0x240 [mac80211]
>  nl80211_dump_survey+0xe7/0x470 [cfg80211]  ? kmalloc_reserve+0x59/0xf0
>  genl_dumpit+0x24/0x70
>  netlink_dump+0x177/0x360
>  __netlink_dump_start+0x206/0x280
>  genl_family_rcv_msg_dumpit.isra.22+0x8a/0xe0
>  ? genl_family_rcv_msg_attrs_parse.isra.23+0xe0/0xe0
>  ? genl_op_lock.part.12+0x10/0x10
>  ? genl_dumpit+0x70/0x70
>  genl_rcv_msg+0x1d0/0x290
>  ? nl80211_del_station+0x330/0x330 [cfg80211]  ?
> genl_get_cmd_both+0x50/0x50
>  netlink_rcv_skb+0x4f/0x100
>  genl_rcv+0x1f/0x30
>  netlink_unicast+0x1b6/0x260
>  netlink_sendmsg+0x31a/0x450
>  __sock_sendmsg+0xa8/0xb0
>  ____sys_sendmsg+0x1e4/0x260
>  ___sys_sendmsg+0x89/0xe0
>  ? local_clock_noinstr+0xb/0xc0
>  ? rcu_is_watching+0xd/0x40
>  ? kfree+0x1de/0x370
>  ? __sys_sendmsg+0x7a/0xc0
> 
> Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.4.1-00199-
> QCAHKSWPL_SILICONZ-1
> 
> Fixes: a9b46dd2e483 ("wifi: ath12k: Add firmware coredump collection support")
> Signed-off-by: Maharaja Kennadyrajan
> <maharaja.kennadyrajan at oss.qualcomm.com>
> ---
>  drivers/net/wireless/ath/ath12k/mhi.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/wireless/ath/ath12k/mhi.c
> b/drivers/net/wireless/ath/ath12k/mhi.c
> index 9c929c4ad8a8..08f44baf182a 100644
> --- a/drivers/net/wireless/ath/ath12k/mhi.c
> +++ b/drivers/net/wireless/ath/ath12k/mhi.c
> @@ -1,7 +1,7 @@
>  // SPDX-License-Identifier: BSD-3-Clause-Clear
>  /*
>   * Copyright (c) 2020-2021 The Linux Foundation. All rights reserved.
> - * Copyright (c) 2021-2024 Qualcomm Innovation Center, Inc. All rights reserved.
> + * Copyright (c) 2021-2025 Qualcomm Innovation Center, Inc. All rights reserved.
>   */
> 
>  #include <linux/msi.h>
> @@ -285,8 +285,11 @@ static void ath12k_mhi_op_status_cb(struct
> mhi_controller *mhi_cntrl,
>                         break;
>                 }
> 
> -               if (!(test_bit(ATH12K_FLAG_UNREGISTERING, &ab->dev_flags)))
> +               if (!(test_bit(ATH12K_FLAG_UNREGISTERING, &ab->dev_flags))) {
> +                       set_bit(ATH12K_FLAG_CRASH_FLUSH, &ab->dev_flags);
> +                       set_bit(ATH12K_FLAG_RECOVERY, &ab->dev_flags);
>                         queue_work(ab->workqueue_aux, &ab->reset_work);
> +               }
>                 break;
>         default:
>                 break;
> 
> base-commit: 176f3009ae598d0523b267db319fe16f69577231
> --
> 2.17.1
>