Re: [ntdev] ISR Handler: Push status register into a queue.

Although this is unsafe, it will work correctly on many common hardware platforms. Especially if the DPC can tolerate duplicate & coalesced bits from the hardware. The coalesced part is an obvious requirement because the hardware may interrupt many times before it can be invoked, and the duplicate part is consistent with good design when possible.

This does appear to be a bug, but its impact will be mitigated by the overall environment. Consistent use of Interlocked operations should resolve the issue.

Sent from Surface Pro

Sent: ‎Thursday‎, ‎July‎ ‎30‎, ‎2015 ‎1‎:‎01‎ ‎PM
To: Windows System Software Devs Interest List

THAT has always been MY understanding.

I suppose whether it matters or not depends on how your DPC is actually written. It seems to ME everyone would sleep better at the cost of an InterlockedOr… or guarding the whole thing with the Interrupt Spin Lock.


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