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

[Hans Zhang]

On 2025/5/17 12:07, Sathyanarayanan Kuppuswamy wrote:
> 
> On 5/16/25 9:55 AM, Hans Zhang wrote:
>> From: Hans Zhang <hans.zhang at 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 at 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.
> 

Dear Sathyanarayanan,

Thank you very much for your reply. You're right. If this series of 
patches is supported in the discussion, I will remove the comment "ACPI 
FADT, PCI bridge quirks" in the next version.

Best regards,
Hans

>> + */
>> +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();
>