Re: [PATCH] mm: don't rely on system state to detect hot-plug operations

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Also, under QEMU, just do a reboot with hotplugged memory and you're in the very same situation.

OK, I didn't know that. I thought the memory would be presented as a normal memory after reboot. Thanks for the clarification.

That's one of the cases where QEMU differs to actual hardware - it's not added to e820, so ACPI always probes+detects+adds DIMMs during boot.

Some people (me :)) consider that a feature and not a BUG.