Re: [PATCH RFC v2 9/9] cxl/pci: Add (hopeful) error handling support

[Jonathan Cameron <Jonathan.Cameron@huawei.com>]

On Fri, 16 Sep 2022 16:11:45 -0700
Dave Jiang <dave.jiang@intel.com> wrote:

> From: Dan Williams <dan.j.williams@intel.com>
> 
> Add nominal error handling that tears down CXL.mem in response to error
> notifications that imply a device reset. Given some CXL.mem may be
> operating as System RAM, there is a high likelihood that these error
> events are fatal. However, if the system survives the notification the
> expectation is that the driver behavior is equivalent to a hot-unplug
> and re-plug of an endpoint.
> 
> Note that this does not change the mask values from the default. That
> awaits CXL _OSC support to determine whether platform firmware is in
> control of the mask registers.

Hi Dave,

So I just implemented correctable error reporting and it never gets
to the handling in here.  My perhaps wrong assumption is that the
device would use ERR_COR messages to indicate those?

They get to the AER handlers (which print appropriately) but because
they have been corrected are never reported to the PCIe drivers.

https://elixir.bootlin.com/linux/latest/source/drivers/pci/pcie/aer.c#L956

I guess we will want a hook for those as well so we can log the
extra info on what the error was when they occur.

Jonathan