Re: [PATCH ath-next 09/16] wifi: ath11k: Power down userPD

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] ath11k: missing reinit_completion() in userPD stop path causes wait bypass
--

commit 73c477b3cddbf3388f54a41a69e207ac4f7c0235
Author: George Moussalem <george.moussalem@outlook.com>

wifi: ath11k: Power down userPD

This commit adds logic to stop the userPD by setting a stop bit in SMEM and
waiting for a completion. It also handles an IPQ5018-specific SCM call to
power down the radio.

> diff --git a/drivers/net/wireless/ath/ath11k/ahb.c b/drivers/net/wireless/ath/ath11k/ahb.c
> index 2c41cf585d001..1b9115311beda 100644
> --- a/drivers/net/wireless/ath/ath11k/ahb.c
> +++ b/drivers/net/wireless/ath/ath11k/ahb.c

[ ... ]

> @@ -491,9 +491,32 @@ static int ath11k_ahb_power_up(struct ath11k_base *ab)
>  	return 0;
>  }
>  
> +static void ath11k_ahb_stop_user_pd(struct ath11k_base *ab)
> +{
> +	struct ath11k_ahb *ab_ahb = ath11k_ahb_priv(ab);
> +	unsigned long time_left;
> +
> +	qcom_smem_state_update_bits(ab_ahb->stop_state, BIT(ab_ahb->stop_bit),
> +				    BIT(ab_ahb->stop_bit));
> +
> +	time_left = wait_for_completion_timeout(&ab_ahb->userpd_stopped,
> +						ATH11K_USERPD_STOP_TIMEOUT);

[Severity: Medium]
Should ab_ahb->userpd_stopped be reinitialized with reinit_completion()
before setting the stop bit in SMEM?

If a previous firmware stop attempt times out (for example, during a crash
recovery) and a late or spurious stop-ack interrupt arrives afterwards, the
userpd_stopped completion could be left in a signaled state.

On the next power down cycle, wait_for_completion_timeout() would
immediately consume the stale completion and return without actually waiting
for the firmware. This bypass could clear the stop bit prematurely and disrupt
the firmware state machine during subsequent error recovery cycles.

> +	if (!time_left)
> +		ath11k_warn(ab, "UserPD stop wait timed out\n");
> +
> +	qcom_smem_state_update_bits(ab_ahb->stop_state, BIT(ab_ahb->stop_bit), 0);
> +
> +	if (ab->hw_rev == ATH11K_HW_IPQ5018_HW10)
> +		qcom_scm_pas_set_wifi_power_mode(MPD_WCNSS_PAS_ID, false);
> +}

[ ... ]

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260923-ipq5018-qcn6122-mpd-v1-0-86729521a75c@outlook.com?part=9