Re: [External] Re: [PATCH 1/3] PCI/AER: Use pci_aer_clear_uncorrect_error_status() to clear uncorrectable error status

[Zhuo Chen <chenzhuo.1@bytedance.com>]

On 9/12/22 12:22 AM, Serge Semin wrote:
> Hi Zhuo
> 
> On Fri, Sep 02, 2022 at 02:16:32AM +0800, Zhuo Chen wrote:
>> Status bits for ERR_NONFATAL errors only are cleared in
>> pci_aer_clear_nonfatal_status(), but we want clear uncorrectable
>> error status in ntb_hw_idt.c and lpfc_attr.c. So we add
>> pci_aer_clear_uncorrect_error_status() and change to use it.
> 
> What about the next drivers
> 
> drivers/scsi/lpfc/lpfc_attr.c
> drivers/crypto/hisilicon/qm.c
> drivers/net/ethernet/intel/ice/ice_main.c
> 
> which call the pci_aer_clear_nonfatal_status() method too?

‘pci_aer_clear_nonfatal_status()’ in 
drivers/net/ethernet/intel/ice/ice_main.c has already been removed and 
merged in kernel in: 
https://github.com/torvalds/linux/commit/ca415ea1f03abf34fc8e4cc5fc30a00189b4e776

‘pci_aer_clear_nonfatal_status()’ in drivers/crypto/hisilicon/qm.c will 
be removed in the next kernel:
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/drivers/crypto/hisilicon/qm.c?id=00278564a60e11df8bcca0ececd8b2f55434e406

Uncorrectable error status register was intended to be cleared in 
drivers/scsi/lpfc/lpfc_attr.c. But originally function was changed in 
https://github.com/torvalds/linux/commit/e7b0b847de6db161e3917732276e425bc92a2feb
and
https://github.com/torvalds/linux/commit/894020fdd88c1e9a74c60b67c0f19f1c7696ba2f
> 
>>
>> Use pci_aer_clear_nonfatal_status() in dpc_process_error(), which has
>> no functional changes.
>>
>> Since pci_aer_clear_nonfatal_status() is used only internally, move
>> its declaration to the PCI internal header file. Also, no one cares
>> about return value of pci_aer_clear_nonfatal_status(), so make it void.
>>
>> Signed-off-by: Zhuo Chen <chenzhuo.1@bytedance.com>
>> ---
>>   drivers/ntb/hw/idt/ntb_hw_idt.c |  4 ++--
>>   drivers/pci/pci.h               |  2 ++
>>   drivers/pci/pcie/aer.c          | 23 ++++++++++++++++++-----
>>   drivers/pci/pcie/dpc.c          |  3 +--
>>   drivers/scsi/lpfc/lpfc_attr.c   |  4 ++--
>>   include/linux/aer.h             |  4 ++--
>>   6 files changed, 27 insertions(+), 13 deletions(-)
>>
>> diff --git a/drivers/ntb/hw/idt/ntb_hw_idt.c b/drivers/ntb/hw/idt/ntb_hw_idt.c
>> index 733557231ed0..de1dbbc5b9de 100644
>> --- a/drivers/ntb/hw/idt/ntb_hw_idt.c
>> +++ b/drivers/ntb/hw/idt/ntb_hw_idt.c
>> @@ -2657,8 +2657,8 @@ static int idt_init_pci(struct idt_ntb_dev *ndev)
>>   	ret = pci_enable_pcie_error_reporting(pdev);
>>   	if (ret != 0)
>>   		dev_warn(&pdev->dev, "PCIe AER capability disabled\n");
> 
>> -	else /* Cleanup nonfatal error status before getting to init */
>> -		pci_aer_clear_nonfatal_status(pdev);
>> +	else /* Cleanup uncorrectable error status before getting to init */
>> +		pci_aer_clear_uncorrect_error_status(pdev);
> 
>  From the IDT NTB PCIe initialization procedure point of view both of
> these methods are equivalent. So for the IDT NTB part:
> 
IDT NTB part is the same as drivers/scsi/lpfc/lpfc_attr.c. The original 
function is clear uncorrectable error status register including fatal 
and non-fatal error status bits.

> Acked-by: Serge Semin <fancer.lancer@gmail.com>
> 
> -Sergey
> 
>>   
>>   	/* First enable the PCI device */
>>   	ret = pcim_enable_device(pdev);
>> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
>> index e10cdec6c56e..574176f43025 100644
>> --- a/drivers/pci/pci.h
>> +++ b/drivers/pci/pci.h
>> @@ -686,6 +686,7 @@ 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;
>>   void pci_aer_clear_fatal_status(struct pci_dev *dev);
>> +void pci_aer_clear_nonfatal_status(struct pci_dev *dev);
>>   int pci_aer_clear_status(struct pci_dev *dev);
>>   int pci_aer_raw_clear_status(struct pci_dev *dev);
>>   #else
>> @@ -693,6 +694,7 @@ static inline void pci_no_aer(void) { }
>>   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) { }
>> +static inline void pci_aer_clear_nonfatal_status(struct pci_dev *dev) { }
>>   static inline int pci_aer_clear_status(struct pci_dev *dev) { return -EINVAL; }
>>   static inline int pci_aer_raw_clear_status(struct pci_dev *dev) { return -EINVAL; }
>>   #endif
>> diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
>> index 7952e5efd6cf..d2996afa80f6 100644
>> --- a/drivers/pci/pcie/aer.c
>> +++ b/drivers/pci/pcie/aer.c
>> @@ -251,13 +251,13 @@ int pci_disable_pcie_error_reporting(struct pci_dev *dev)
>>   }
>>   EXPORT_SYMBOL_GPL(pci_disable_pcie_error_reporting);
>>   
>> -int pci_aer_clear_nonfatal_status(struct pci_dev *dev)
>> +void pci_aer_clear_nonfatal_status(struct pci_dev *dev)
>>   {
>>   	int aer = dev->aer_cap;
>>   	u32 status, sev;
>>   
>>   	if (!pcie_aer_is_native(dev))
>> -		return -EIO;
>> +		return;
>>   
>>   	/* Clear status bits for ERR_NONFATAL errors only */
>>   	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
>> @@ -265,10 +265,7 @@ int pci_aer_clear_nonfatal_status(struct pci_dev *dev)
>>   	status &= ~sev;
>>   	if (status)
>>   		pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
>> -
>> -	return 0;
>>   }
>> -EXPORT_SYMBOL_GPL(pci_aer_clear_nonfatal_status);
>>   
>>   void pci_aer_clear_fatal_status(struct pci_dev *dev)
>>   {
>> @@ -286,6 +283,22 @@ void pci_aer_clear_fatal_status(struct pci_dev *dev)
>>   		pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
>>   }
>>   
>> +int pci_aer_clear_uncorrect_error_status(struct pci_dev *dev)
>> +{
>> +	int aer = dev->aer_cap;
>> +	u32 status;
>> +
>> +	if (!pcie_aer_is_native(dev))
>> +		return -EIO;
>> +
>> +	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
>> +	if (status)
>> +		pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
>> +
>> +	return 0;
>> +}
>> +EXPORT_SYMBOL_GPL(pci_aer_clear_uncorrect_error_status);
>> +
>>   /**
>>    * pci_aer_raw_clear_status - Clear AER error registers.
>>    * @dev: the PCI device
>> diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c
>> index 3e9afee02e8d..7942073fbb34 100644
>> --- a/drivers/pci/pcie/dpc.c
>> +++ b/drivers/pci/pcie/dpc.c
>> @@ -288,8 +288,7 @@ void dpc_process_error(struct pci_dev *pdev)
>>   		 dpc_get_aer_uncorrect_severity(pdev, &info) &&
>>   		 aer_get_device_error_info(pdev, &info)) {
>>   		aer_print_error(pdev, &info);
>> -		pci_aer_clear_nonfatal_status(pdev);
>> -		pci_aer_clear_fatal_status(pdev);
>> +		pci_aer_clear_uncorrect_error_status(pdev);
>>   	}
>>   }
>>   
>> diff --git a/drivers/scsi/lpfc/lpfc_attr.c b/drivers/scsi/lpfc/lpfc_attr.c
>> index 3caaa7c4af48..1ed8d1640325 100644
>> --- a/drivers/scsi/lpfc/lpfc_attr.c
>> +++ b/drivers/scsi/lpfc/lpfc_attr.c
>> @@ -4712,7 +4712,7 @@ static DEVICE_ATTR_RW(lpfc_aer_support);
>>    * Description:
>>    * If the @buf contains 1 and the device currently has the AER support
>>    * enabled, then invokes the kernel AER helper routine
>> - * pci_aer_clear_nonfatal_status() to clean up the uncorrectable
>> + * pci_aer_clear_uncorrect_error_status() to clean up the uncorrectable
>>    * error status register.
>>    *
>>    * Notes:
>> @@ -4738,7 +4738,7 @@ lpfc_aer_cleanup_state(struct device *dev, struct device_attribute *attr,
>>   		return -EINVAL;
>>   
>>   	if (phba->hba_flag & HBA_AER_ENABLED)
>> -		rc = pci_aer_clear_nonfatal_status(phba->pcidev);
>> +		rc = pci_aer_clear_uncorrect_error_status(phba->pcidev);
>>   
>>   	if (rc == 0)
>>   		return strlen(buf);
>> diff --git a/include/linux/aer.h b/include/linux/aer.h
>> index 97f64ba1b34a..f638ad955deb 100644
>> --- a/include/linux/aer.h
>> +++ b/include/linux/aer.h
>> @@ -44,7 +44,7 @@ struct aer_capability_regs {
>>   /* PCIe port driver needs this function to enable AER */
>>   int pci_enable_pcie_error_reporting(struct pci_dev *dev);
>>   int pci_disable_pcie_error_reporting(struct pci_dev *dev);
>> -int pci_aer_clear_nonfatal_status(struct pci_dev *dev);
>> +int pci_aer_clear_uncorrect_error_status(struct pci_dev *dev);
>>   void pci_save_aer_state(struct pci_dev *dev);
>>   void pci_restore_aer_state(struct pci_dev *dev);
>>   #else
>> @@ -56,7 +56,7 @@ static inline int pci_disable_pcie_error_reporting(struct pci_dev *dev)
>>   {
>>   	return -EINVAL;
>>   }
>> -static inline int pci_aer_clear_nonfatal_status(struct pci_dev *dev)
>> +static inline int pci_aer_clear_uncorrect_error_status(struct pci_dev *dev)
>>   {
>>   	return -EINVAL;
>>   }
>> -- 
>> 2.30.1 (Apple Git-130)
>>

-- 
Thanks,
Zhuo Chen