Re: [PATCH 2/3] remoteproc: core: full attach detach during recovery

[Iuliana Prodan <iuliana.prodan@nxp.com>]

Hi Tanmay,

On 10/28/2025 6:57 AM, Tanmay Shah wrote:
> Current attach on recovery mechanism loads the clean resource table
> during recovery, but doesn't re-allocate the resources. RPMsg
> communication will fail after recovery due to this. Fix this
> incorrect behavior by doing the full detach and attach of remote
> processor during the recovery. This will load the clean resource table
> and re-allocate all the resources, which will set up correct vring
> information in the resource table.
> 
> Signed-off-by: Tanmay Shah <tanmay.shah@amd.com>
> ---
>   drivers/remoteproc/remoteproc_core.c | 22 +++++++++++++---------
>   1 file changed, 13 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index aada2780b343..f5b078fe056a 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -1777,11 +1777,11 @@ static int rproc_attach_recovery(struct rproc *rproc)
>   {
>   	int ret;
>   
> -	ret = __rproc_detach(rproc);
> +	ret = rproc_detach(rproc);
>   	if (ret)
>   		return ret;
>   
> -	return __rproc_attach(rproc);
> +	return rproc_attach(rproc);
>   }
>   
>   static int rproc_boot_recovery(struct rproc *rproc)
> @@ -1829,6 +1829,9 @@ int rproc_trigger_recovery(struct rproc *rproc)
>   	struct device *dev = &rproc->dev;
>   	int ret;
>   
> +	if (rproc_has_feature(rproc, RPROC_FEAT_ATTACH_ON_RECOVERY))
> +		return rproc_attach_recovery(rproc);
> +
>   	ret = mutex_lock_interruptible(&rproc->lock);
>   	if (ret)
>   		return ret;
> @@ -1839,10 +1842,7 @@ int rproc_trigger_recovery(struct rproc *rproc)
>   
>   	dev_err(dev, "recovering %s\n", rproc->name);

Please move the log message above the new early return so both paths log 
recovery.
>   
> -	if (rproc_has_feature(rproc, RPROC_FEAT_ATTACH_ON_RECOVERY))
> -		ret = rproc_attach_recovery(rproc);
> -	else
> -		ret = rproc_boot_recovery(rproc);
> +	ret = rproc_boot_recovery(rproc);
>   
>   unlock_mutex:
>   	mutex_unlock(&rproc->lock);
> @@ -1860,6 +1860,7 @@ static void rproc_crash_handler_work(struct work_struct *work)
>   {
>   	struct rproc *rproc = container_of(work, struct rproc, crash_handler);
>   	struct device *dev = &rproc->dev;
> +	int ret;
>   
>   	dev_dbg(dev, "enter %s\n", __func__);
>   
> @@ -1883,8 +1884,11 @@ static void rproc_crash_handler_work(struct work_struct *work)
>   
>   	mutex_unlock(&rproc->lock);
>   
> -	if (!rproc->recovery_disabled)
> -		rproc_trigger_recovery(rproc);
> +	if (!rproc->recovery_disabled) {
> +		ret = rproc_trigger_recovery(rproc);
> +		if (ret)
> +			dev_warn(dev, "rproc recovery failed, err %d\n", ret);
> +	}
>   
>   out:
>   	pm_relax(rproc->dev.parent);
> @@ -2057,7 +2061,7 @@ int rproc_detach(struct rproc *rproc)
>   		return ret;
>   	}
>   
> -	if (rproc->state != RPROC_ATTACHED) {
> +	if (rproc->state != RPROC_ATTACHED && rproc->state != RPROC_CRASHED) {
>   		ret = -EINVAL;
>   		goto out;
>   	}
Tested this on i.MX8M Plus using the imx_dsp_rproc driver, which 
supports recovery.
Everything looks good, but on imx_dsp_rproc we use rproc_boot_recovery, 
not rproc_attach_recovery, where most of the changes happened.

Iulia