On 7/28/24 12:59, Wolfram Sang wrote:
Hi Guenter,
as I mentioned before I now have to deal with SMBusAlert as well and had
a chance to review and test this series. When developing the SMBAlert
trigger mechanism for the i2c testunit, I also experienced the interrupt
storm and your patches helped. See later mails for details.
Note that there is one situation which is not addressed by this set of
patches: If the corrupted address points to yet another device with alert
handler on the same bus, the alert handler of that device will be called.
If it is not a source of the alert, we are back to the original problem.
I do not know how to address this case.
I think this can only work if we require .alert-handlers to start with a
sanity check to make sure their device really raised an interrupt
condition. And then return either -EBUSY or 0, similar to IRQ_HANDLED or
IRQ_NONE. Or?
I think so, but I am not sure if it is worth the effort. It would require
changing the API, and each driver supporting alert callbacks would have
to implement code to detect if it actually got an interrupt.
Thanks,
Guenter
