Re: [PATCH] net: atlantic: only free the PTP IRQ after a successful request

[Runyu Xiao]

Hi Simon,

> Whether the issue was actually triggered, or is only theoretical
> (e.g. found by code inspection). If it was triggered please include
> the symptoms, like the stack trace or error messages.
>
> What hardware the change was tested on. For driver fixes please
> mention the device (and if relevant firmware version) used for
> testing, or say that the change was not tested on real hardware.

The issue was identified by code inspection and was not reproduced at
runtime. In legacy INTx mode, aq_ptp_irq_alloc() skips request_irq() and
returns -EINVAL. The aq_ndev_open() error path then calls aq_nic_stop(),
which invokes aq_ptp_irq_free(); before this change, that path could call
free_irq() without a matching request_irq(). The expected IRQ-core warning
is "Trying to free already-free IRQ", but I did not capture a runtime
warning or stack trace.

I did not test this on real Aquantia Atlantic hardware or firmware.

Thanks,
Runyu