Re: [PATCH] remoteproc: qcom_q6v5_mss: Fix off-by-one error in regulator error cleanup

[Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>]

On 7/10/26 9:46 PM, Sailesh Nandanavanam wrote:
> In q6v5_regulator_enable(), when any operation fails for regulator at
> index 'i', the error cleanup path unconditionally calls
> regulator_disable() starting from index 'i'. However, regulator 'i'
> was never successfully enabled at this point, resulting in an
> unbalanced disable.
> 
> There are three distinct failure points:
> - regulator_set_voltage() failure: voltage was never set, load was
> never set, regulator was never enabled.
> - regulator_set_load() failure: voltage was set, but regulator was
> never enabled.
> - regulator_enable() failure: voltage and load were set, but
> regulator was never enabled.
> 
> Fix this by introducing three separate error labels to handle each
> failure point correctly. For the failing regulator at index 'i',
> only reset the resources that were actually configured, without
> calling regulator_disable(). Then roll back all previously enabled
> regulators using 'i--' in the for loop initializer to skip the
> never-enabled regulator.
> 
> Fixes: 19f902b53b47 ("remoteproc: qcom: Initialize and enable proxy and active regulators.")
> Cc: stable@vger.kernel.org
> Signed-off-by: Sailesh Nandanavanam <saileshnandanavanam@gmail.com>
> ---

[...]

> -err:
> -	for (; i >= 0; i--) {
> +err_enable:
> +	if (regs[i].uA > 0)
> +		regulator_set_load(regs[i].reg, 0);
> +err_set_load:
> +	if (regs[i].uV > 0)
> +		regulator_set_voltage(regs[i].reg, 0, INT_MAX);

The first two labels only unwind a single regulator

Konrad