Re: [PATCH 3/4] PCI/AER: Expose AER panic state via pci_aer_panic_enabled()

[Sathyanarayanan Kuppuswamy <sathyanarayanan.kuppuswamy@linux.intel.com>]

On 5/16/25 9:55 AM, Hans Zhang wrote:
> From: Hans Zhang <hans.zhang@cixtech.com>
>
> Add pci_aer_panic_enabled() to check if aer_panic is enabled system-wide.
> Export the function for use in error recovery logic.
>
> Signed-off-by: Hans Zhang <hans.zhang@cixtech.com>
> ---
>   drivers/pci/pci.h      |  2 ++
>   drivers/pci/pcie/aer.c | 12 ++++++++++++
>   2 files changed, 14 insertions(+)
>
> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
> index 8ddfc1677eeb..f92928dadc6a 100644
> --- a/drivers/pci/pci.h
> +++ b/drivers/pci/pci.h
> @@ -959,6 +959,7 @@ static inline void of_pci_remove_host_bridge_node(struct pci_host_bridge *bridge
>   #ifdef CONFIG_PCIEAER
>   void pci_no_aer(void);
>   void pci_aer_panic(void);
> +bool pci_aer_panic_enabled(void);
>   void pci_aer_init(struct pci_dev *dev);
>   void pci_aer_exit(struct pci_dev *dev);
>   extern const struct attribute_group aer_stats_attr_group;
> @@ -970,6 +971,7 @@ void pci_restore_aer_state(struct pci_dev *dev);
>   #else
>   static inline void pci_no_aer(void) { }
>   static inline void pci_aer_panic(void) { }
> +static inline bool pci_aer_panic_enabled(void) { return false; }
>   static inline void pci_aer_init(struct pci_dev *d) { }
>   static inline void pci_aer_exit(struct pci_dev *d) { }
>   static inline void pci_aer_clear_fatal_status(struct pci_dev *dev) { }
> diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
> index fa51fb8a5fe7..4fd7db90b77c 100644
> --- a/drivers/pci/pcie/aer.c
> +++ b/drivers/pci/pcie/aer.c
> @@ -125,6 +125,18 @@ void pci_aer_panic(void)
>   	pcie_aer_panic = true;
>   }
>   
> +/**
> + * pci_aer_panic_enabled() - Are AER panic enabled system-wide?
> + *
> + * Return: true if AER panic has not been globally disabled through ACPI FADT,
> + * PCI bridge quirks, or the "pci=aer_panic" kernel command-line option.

I don't think we have code to disable it via ACPI FADT or PCI bridge quirks
currently, right? If yes, just list what is currently supported.

> + */
> +bool pci_aer_panic_enabled(void)
> +{
> +	return pcie_aer_panic;
> +}
> +EXPORT_SYMBOL(pci_aer_panic_enabled);
> +
>   bool pci_aer_available(void)
>   {
>   	return !pcie_aer_disable && pci_msi_enabled();

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer