On Mon, Dec 4, 2017 at 12:28 PM, Andrea Reale [off-list ref] wrote:

Hi Joey,

and thanks for your comments. Response inline:

[cut]

quoted

So, the BUG() is useful to capture state issue in memory subsystem. But, I
understood your concern about the two steps offline/remove from userland.

Maybe we should move the BUG() to somewhere but not just remove it. Or if
we think that the BUG() is too intense, at least we should print out a error
message, and ACPI should checks the return value from subsystem to
interrupt memory-hotplug process.

In this patchset, BUG() is moved to acpi_memory_remove_memory(),
the caller of arch_remove_memory(). However, I agree with Michal, that
we should not BUG() here but rather halt the hotremove process and print
some errors.
Is there any state in ACPI that should be undone in case of hotremove
errors or we can just stop the process "halfway"?

I have to recall a couple of things before answering this question, so
that may take some time.

Thanks,
Rafael