Re: [PATCH 2/3] Mini-OS: don't crash if no shutdown node is available

[Juergen Gross <jgross@suse.com>]

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On 01.11.23 17:38, Andrew Cooper wrote:
> On 01/11/2023 9:00 am, Juergen Gross wrote:
>> It might be perfectly fine not to have a control/shutdown Xenstore
>> node. If this is the case, don't crash, but just terminate the
>> shutdown thread after issuing a message that shutdown isn't available.
>>
>> In fini_shutdown() clearing the watch can result in an error now, in
>> case the early exit above was taken. Just ignore this error now.
>>
>> Signed-off-by: Juergen Gross <jgross@suse.com>
> 
> Which cases might we not have a control/shutdown node?

Xenstore-stubdom. It should _never_ shutdown, and it isn't really under
control of Xen tools (other than being created).

> I'm all for coping better with its absence, but it's not a piece of the
> Xen ABI which is optional.

I'd like to differ here. See reasoning above.

> And on that front, not crashing is good, but why remove the watch?  What
> if it comes into existence later?  Is there any problem with just
> leaving the watch outstanding?

A needless waste of memory in Xenstore-stubdom.


Juergen

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