[dpdk-dev] Question about hardware error handling policy

[fengchengwen <fengchengwen@huawei.com>]

Hi, all

    I notice ethdev support dev_reset ops, which could be used to recover from
errors, and only 13+ drivers support this function.
    And also there is event for reset: RTE_ETH_EVENT_INTR_RESET, and only 6
drivers support it (most of them are VF).

    This provides users with two ways to handle hardware errors:
    a. driver report RTE_ETH_EVENT_INTR_RESET, and application do reset ops.
    b. application detect errors (the detection method is unclear), and call
    reset ops to recover.

    According to the design of this API, error handling is assigned to the
application, and the driver is only responsible for reporting events. This
simplifies the driver design (for example, the driver does not need to maintain
mutex locks).

    As we know, many modern NICs come with firmware, have PCIE interfaces,
support SR-IOV, the hardware errors can have: firmware reboot/PF reset/
VF reset/FLR, but these errors(particularly firmware/PF) are not addressed in
most drivers.

    Question 1: what do we think of these errors(particularly firmware/PF)? Do
we think that the probability is very low and that there is no need to deal with
them?
    Question 2: I prefer to put error handling in the application layer, because
doing it in the driver can make the driver complex, but there is no app to
register the INTR_RESET event handler. I think we can build a standard handler
in testpmd, What do you think?

Thanks