Re: [PATCH] spi: pic32-sqi: guard against empty BD list in pic32_sqi_one_message()

[Mark Brown]

> Fix it by bailing out with -EINVAL when bd_list_used is empty, before
> both list_last_entry() and list_first_entry(). The xfer_out cleanup path
> tolerates an empty list, and normal messages with at least one transfer
> are unaffected. This also matches the existing list_empty() guard in
> ring_desc_get() in the same file.

>  
> +	/* a message with no transfers leaves the BD list empty */

The core will reject a message with no transfers, it will allow a
message where none of the transfers have a tx_buf or rx_buf.

> +	if (list_empty(&sqi->bd_list_used)) {
> +		ret = -EINVAL;
> +		goto xfer_out;

We need to update msg->status too, the timeout path below does the right
thing here.

-- 
Mark Brown <broonie@xxxxxxxxxx>