[v9] Enable CXL PCIe port protocol error handling and logging

[PATCH v9 11/16] cxl/pci: Update __cxl_handle_cor_ras() to return early if no RAS errors

Posted by Terry Bowman 6 months, 2 weeks ago

__cxl_handle_cor_ras() is missing logic to leave the function early in the
case there is no RAS error. Update __cxl_handle_cor_ras() to exit early in
the case there is no RAS errors detected after applying the mask.

Signed-off-by: Terry Bowman <terry.bowman@amd.com>
---
 drivers/cxl/core/pci.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
index 0f4c07fd64a5..f5f87c2c3fd5 100644
--- a/drivers/cxl/core/pci.c
+++ b/drivers/cxl/core/pci.c
@@ -677,10 +677,11 @@ static void __cxl_handle_cor_ras(struct device *dev, u64 serial,
 
 	addr = ras_base + CXL_RAS_CORRECTABLE_STATUS_OFFSET;
 	status = readl(addr);
-	if (status & CXL_RAS_CORRECTABLE_STATUS_MASK) {
-		writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
-		trace_cxl_aer_correctable_error(dev, serial, status);
-	}
+	if (!(status & CXL_RAS_CORRECTABLE_STATUS_MASK))
+		return;
+	writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
+
+	trace_cxl_aer_correctable_error(dev, serial, status);
 }
 
 static void cxl_handle_endpoint_cor_ras(struct cxl_dev_state *cxlds)
-- 
2.34.1

Re: [PATCH v9 11/16] cxl/pci: Update __cxl_handle_cor_ras() to return early if no RAS errors

Posted by Jonathan Cameron 6 months, 1 week ago

On Tue, 3 Jun 2025 12:22:34 -0500
Terry Bowman <terry.bowman@amd.com> wrote:

> __cxl_handle_cor_ras() is missing logic to leave the function early in the
> case there is no RAS error. Update __cxl_handle_cor_ras() to exit early in
> the case there is no RAS errors detected after applying the mask.

I'm all for this as sensible cleanup, but the 'missing' kind
of suggest a bug to me whereas I don't see one.
Perhaps reword?

> 
> Signed-off-by: Terry Bowman <terry.bowman@amd.com>
> ---
>  drivers/cxl/core/pci.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
> index 0f4c07fd64a5..f5f87c2c3fd5 100644
> --- a/drivers/cxl/core/pci.c
> +++ b/drivers/cxl/core/pci.c
> @@ -677,10 +677,11 @@ static void __cxl_handle_cor_ras(struct device *dev, u64 serial,
>  
>  	addr = ras_base + CXL_RAS_CORRECTABLE_STATUS_OFFSET;
>  	status = readl(addr);
> -	if (status & CXL_RAS_CORRECTABLE_STATUS_MASK) {
> -		writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
> -		trace_cxl_aer_correctable_error(dev, serial, status);
> -	}
> +	if (!(status & CXL_RAS_CORRECTABLE_STATUS_MASK))
> +		return;
> +	writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
> +
> +	trace_cxl_aer_correctable_error(dev, serial, status);
>  }
>  
>  static void cxl_handle_endpoint_cor_ras(struct cxl_dev_state *cxlds)

Re: [PATCH v9 11/16] cxl/pci: Update __cxl_handle_cor_ras() to return early if no RAS errors

Posted by Bowman, Terry 6 months ago

On 6/12/2025 11:46 AM, Jonathan Cameron wrote:
> On Tue, 3 Jun 2025 12:22:34 -0500
> Terry Bowman <terry.bowman@amd.com> wrote:
> 
>> __cxl_handle_cor_ras() is missing logic to leave the function early in the
>> case there is no RAS error. Update __cxl_handle_cor_ras() to exit early in
>> the case there is no RAS errors detected after applying the mask.
> 
> I'm all for this as sensible cleanup, but the 'missing' kind
> of suggest a bug to me whereas I don't see one.
> Perhaps reword?
> 

Yes, I will reword the commit message.

-Terry

>>
>> Signed-off-by: Terry Bowman <terry.bowman@amd.com>
>> ---
>>  drivers/cxl/core/pci.c | 9 +++++----
>>  1 file changed, 5 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
>> index 0f4c07fd64a5..f5f87c2c3fd5 100644
>> --- a/drivers/cxl/core/pci.c
>> +++ b/drivers/cxl/core/pci.c
>> @@ -677,10 +677,11 @@ static void __cxl_handle_cor_ras(struct device *dev, u64 serial,
>>  
>>  	addr = ras_base + CXL_RAS_CORRECTABLE_STATUS_OFFSET;
>>  	status = readl(addr);
>> -	if (status & CXL_RAS_CORRECTABLE_STATUS_MASK) {
>> -		writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
>> -		trace_cxl_aer_correctable_error(dev, serial, status);
>> -	}
>> +	if (!(status & CXL_RAS_CORRECTABLE_STATUS_MASK))
>> +		return;
>> +	writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
>> +
>> +	trace_cxl_aer_correctable_error(dev, serial, status);
>>  }
>>  
>>  static void cxl_handle_endpoint_cor_ras(struct cxl_dev_state *cxlds)
>

Re: [PATCH v9 11/16] cxl/pci: Update __cxl_handle_cor_ras() to return early if no RAS errors

Posted by Dave Jiang 6 months, 2 weeks ago


On 6/3/25 10:22 AM, Terry Bowman wrote:
> __cxl_handle_cor_ras() is missing logic to leave the function early in the
> case there is no RAS error. Update __cxl_handle_cor_ras() to exit early in
> the case there is no RAS errors detected after applying the mask.

This change is small enough that I would just fold it into the patch that introduces this function.

DJ

> 
> Signed-off-by: Terry Bowman <terry.bowman@amd.com>
> ---
>  drivers/cxl/core/pci.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
> index 0f4c07fd64a5..f5f87c2c3fd5 100644
> --- a/drivers/cxl/core/pci.c
> +++ b/drivers/cxl/core/pci.c
> @@ -677,10 +677,11 @@ static void __cxl_handle_cor_ras(struct device *dev, u64 serial,
>  
>  	addr = ras_base + CXL_RAS_CORRECTABLE_STATUS_OFFSET;
>  	status = readl(addr);
> -	if (status & CXL_RAS_CORRECTABLE_STATUS_MASK) {
> -		writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
> -		trace_cxl_aer_correctable_error(dev, serial, status);
> -	}
> +	if (!(status & CXL_RAS_CORRECTABLE_STATUS_MASK))
> +		return;
> +	writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
> +
> +	trace_cxl_aer_correctable_error(dev, serial, status);
>  }
>  
>  static void cxl_handle_endpoint_cor_ras(struct cxl_dev_state *cxlds)

Re: [PATCH v9 11/16] cxl/pci: Update __cxl_handle_cor_ras() to return early if no RAS errors

Posted by Bowman, Terry 6 months, 2 weeks ago


On 6/6/2025 3:30 PM, Dave Jiang wrote:
>
> On 6/3/25 10:22 AM, Terry Bowman wrote:
>> __cxl_handle_cor_ras() is missing logic to leave the function early in the
>> case there is no RAS error. Update __cxl_handle_cor_ras() to exit early in
>> the case there is no RAS errors detected after applying the mask.
> This change is small enough that I would just fold it into the patch that introduces this function.
>
> DJ
I agree. The problem is it was already present before this series. This is a 'fix'. I had this change in:
[PATCH v9 09/16] cxl/pci: Log message if RAS registers are unmapped
but was asked to move out because it appeared as an unrelated miscellaneous patch.

Terry
>> Signed-off-by: Terry Bowman <terry.bowman@amd.com>
>> ---
>>  drivers/cxl/core/pci.c | 9 +++++----
>>  1 file changed, 5 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
>> index 0f4c07fd64a5..f5f87c2c3fd5 100644
>> --- a/drivers/cxl/core/pci.c
>> +++ b/drivers/cxl/core/pci.c
>> @@ -677,10 +677,11 @@ static void __cxl_handle_cor_ras(struct device *dev, u64 serial,
>>  
>>  	addr = ras_base + CXL_RAS_CORRECTABLE_STATUS_OFFSET;
>>  	status = readl(addr);
>> -	if (status & CXL_RAS_CORRECTABLE_STATUS_MASK) {
>> -		writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
>> -		trace_cxl_aer_correctable_error(dev, serial, status);
>> -	}
>> +	if (!(status & CXL_RAS_CORRECTABLE_STATUS_MASK))
>> +		return;
>> +	writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
>> +
>> +	trace_cxl_aer_correctable_error(dev, serial, status);
>>  }
>>  
>>  static void cxl_handle_endpoint_cor_ras(struct cxl_dev_state *cxlds)

Re: [PATCH v9 11/16] cxl/pci: Update __cxl_handle_cor_ras() to return early if no RAS errors

Posted by Dave Jiang 6 months, 2 weeks ago


On 6/6/25 1:55 PM, Bowman, Terry wrote:
> 
> 
> On 6/6/2025 3:30 PM, Dave Jiang wrote:
>>
>> On 6/3/25 10:22 AM, Terry Bowman wrote:
>>> __cxl_handle_cor_ras() is missing logic to leave the function early in the
>>> case there is no RAS error. Update __cxl_handle_cor_ras() to exit early in
>>> the case there is no RAS errors detected after applying the mask.
>> This change is small enough that I would just fold it into the patch that introduces this function.
>>
>> DJ
> I agree. The problem is it was already present before this series. This is a 'fix'. I had this change in:
> [PATCH v9 09/16] cxl/pci: Log message if RAS registers are unmapped
> but was asked to move out because it appeared as an unrelated miscellaneous patch.

Ok. Then

Reviewed-by: Dave Jiang <dave.jiang@intel.com>

> 
> Terry
>>> Signed-off-by: Terry Bowman <terry.bowman@amd.com>
>>> ---
>>>  drivers/cxl/core/pci.c | 9 +++++----
>>>  1 file changed, 5 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
>>> index 0f4c07fd64a5..f5f87c2c3fd5 100644
>>> --- a/drivers/cxl/core/pci.c
>>> +++ b/drivers/cxl/core/pci.c
>>> @@ -677,10 +677,11 @@ static void __cxl_handle_cor_ras(struct device *dev, u64 serial,
>>>  
>>>  	addr = ras_base + CXL_RAS_CORRECTABLE_STATUS_OFFSET;
>>>  	status = readl(addr);
>>> -	if (status & CXL_RAS_CORRECTABLE_STATUS_MASK) {
>>> -		writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
>>> -		trace_cxl_aer_correctable_error(dev, serial, status);
>>> -	}
>>> +	if (!(status & CXL_RAS_CORRECTABLE_STATUS_MASK))
>>> +		return;
>>> +	writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
>>> +
>>> +	trace_cxl_aer_correctable_error(dev, serial, status);
>>>  }
>>>  
>>>  static void cxl_handle_endpoint_cor_ras(struct cxl_dev_state *cxlds)
>

Re: [PATCH v9 11/16] cxl/pci: Update __cxl_handle_cor_ras() to return early if no RAS errors

Posted by Sathyanarayanan Kuppuswamy 6 months, 2 weeks ago

On 6/3/25 10:22 AM, Terry Bowman wrote:
> __cxl_handle_cor_ras() is missing logic to leave the function early in the
> case there is no RAS error. Update __cxl_handle_cor_ras() to exit early in
> the case there is no RAS errors detected after applying the mask.
>
> Signed-off-by: Terry Bowman <terry.bowman@amd.com>
> ---
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
>   drivers/cxl/core/pci.c | 9 +++++----
>   1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
> index 0f4c07fd64a5..f5f87c2c3fd5 100644
> --- a/drivers/cxl/core/pci.c
> +++ b/drivers/cxl/core/pci.c
> @@ -677,10 +677,11 @@ static void __cxl_handle_cor_ras(struct device *dev, u64 serial,
>   
>   	addr = ras_base + CXL_RAS_CORRECTABLE_STATUS_OFFSET;
>   	status = readl(addr);
> -	if (status & CXL_RAS_CORRECTABLE_STATUS_MASK) {
> -		writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
> -		trace_cxl_aer_correctable_error(dev, serial, status);
> -	}
> +	if (!(status & CXL_RAS_CORRECTABLE_STATUS_MASK))
> +		return;
> +	writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
> +
> +	trace_cxl_aer_correctable_error(dev, serial, status);
>   }
>   
>   static void cxl_handle_endpoint_cor_ras(struct cxl_dev_state *cxlds)

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer