Re: [PATCH v2 1/2] ufs: always notify POST_CHANGE even on gear switch failure

["Peter Wang (王信友)" <peter.wang@mediatek.com>]

On Mon, 2026-09-14 at 09:02 +0000, sashiko-bot@kernel.org wrote
> 
> [Severity: Medium]
> Will passing NULL for dev_req_params on failure cause issues for
> unmodified
> vendor drivers?
> 
> Looking at ufs_qcom_pwr_change_notify() in drivers/ufs/host/ufs-
> qcom.c, it
> has an early check that will trap this NULL argument and log a
> spurious error
> before any POST_CHANGE cleanup can execute:
> 
> drivers/ufs/host/ufs-qcom.c:ufs_qcom_pwr_change_notify() {
> 	if (!dev_req_params) {
> 		pr_err("%s: incoming dev_req_params is NULL\n",
> __func__);
> 		return -EINVAL;
> 	}
> 	...
> }
> 
> Similarly, ufs_hisi_pwr_change_notify() in drivers/ufs/host/ufs-
> hisi.c will
> also log a spurious error on every power mode change failure:
> 
> drivers/ufs/host/ufs-hisi.c:ufs_hisi_pwr_change_notify() {
> 	if (!dev_req_params) {
> 		dev_err(hba->dev,
> 			    "%s: incoming dev_req_params is NULL\n",
> __func__);
> 		ret = -EINVAL;
> 		goto out;
> 	}
> 	...
> }
> 

Yes, both the qcom and hisi host drivers ignore NULL and only print an
error log that indicates a power‑mode‑change failure.


> Additionally, does passing NULL here destroy the context needed for
> proper
> resource rollback?
> 
> For instance, in ufs_qcom_pwr_change_notify(), resources are acquired
> in
> PRE_CHANGE based on the dev_req_params:
> 

This patch doesn't change the behavior of the qcom driver.

Thanks
Peter