Re: [PATCH v4 07/10] scsi: ufs: Simplify error handling preparation

[Bart Van Assche]

On 6/23/21 12:35 AM, Can Guo wrote:
> -static void ufshcd_err_handling_prepare(struct ufs_hba *hba)
> +static int ufshcd_err_handling_prepare(struct ufs_hba *hba)
>  {
>  	/*
>  	 * It is not safe to perform error handling while suspend or resume is
>  	 * in progress. Hence the lock_system_sleep() call.
>  	 */
>  	lock_system_sleep();
> +	/*
> +	 * Exclusively call pm_runtime_get_sync(hba->dev) once, in case
> +	 * following ufshcd_rpm_get_sync() fails.
> +	 */
> +	pm_runtime_get_sync(hba->dev);
> +	if (pm_runtime_suspended(hba->dev) || hba->is_sys_suspended) {
> +		pm_runtime_put(hba->dev);
> +		unlock_system_sleep();
> +		return -EINVAL;
> +	}

There is code present in ufshcd_queuecommand() that may trigger data
corruption to prevent that the above pm_runtime_get_sync() call triggers
a deadlock. I think we need a better solution.

Thanks,

Bart.