Re: [PATCH 2/4] pci/aer: Handle Advisory Non-Fatal properly

[Bjorn Helgaas <helgaas@kernel.org>]

On Thu, Jan 11, 2024 at 03:32:17PM +0800, Wang, Qingshun wrote:
> If we are processing an Advisory Non-Fatal Error, first check the Device
> Status. If any of Fatal/Non-Fatal Error Detected bits is set, leave it
> to uncorrectable error handler to clear the UE status bit, which should
> be executed right after the CE handler in this case.
> 
> Otherwise, filter out uncorrectable errors that is not possible to
> trigger an Advisory Non-Fatal Error, then clear all the rest status bits.

> +static int anfe_get_related_err(struct aer_err_info *info)
> +{
> +	/*
> +	 * Take the most conservative route here. If there are
> +	 * Non-Fatal/Fatal errors detected, do not assume any
> +	 * bit in uncor_status is set by ANFE.
> +	 */
> +	if (info->device_status & (PCI_EXP_DEVSTA_NFED | PCI_EXP_DEVSTA_FED))
> +		return 0;
> +	/*
> +	 * An UNCOR error may cause Advisory Non-Fatal error if:
> +	 *	a. The severity of the error is Non-Fatal.
> +	 *	b. The error is one of the following:
> +	 *		1. Poisoned TLP
> +	 *		2. Completion Timeout
> +	 *		3. Completer Abort
> +	 *		4. Unexpected Completion
> +	 *		5. Unsupported Request

This could benefit from a reference to the spec that outlines these
conditions.

Bjorn