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Issue with MSI-X message masked at boot up

jlabriejlabrie Member Posts: 1


we have a MSI-X device that supports 4 messages and we are using a WDM driver (legacy code base) with IoConnectInterruptEx. The interrupt connection works for all 4 messages and we do not get any error. But, if I look at the MSI-X table entry, on some system, I see the control field to be 1 meaning it is masked. Sometimes the msg data is 0 or a value.

In the working system, I dump the value of the MSI-X table and see the control being 0 even before calling IoConnectInterruptEx. On the non-working system, I see 1 even after IoConnectInterruptEx.

By disabling the driver and reenabling it, the MSI-X table gets populated correctly. Also I have Windows 10 2004. I did swap the hard disk and the problem stays with the system.

My question is, who does the filling up of the MSI-X table and when?

thanks for any pointers or stuff to look at.

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