Re: [PATCH] xen/page_alloc: Simplify domain_adjust_tot_pages

[Jan Beulich <jbeulich@xxxxxxxx>]

On 11.03.2025 10:46, Alejandro Vallejo wrote:
> On Wed Mar 5, 2025 at 1:39 PM GMT, Jan Beulich wrote:
>>> It's all quite perverse. Fortunately, looking at adjacent claims-related 
>>> code
>>> xl seems to default to making a claim prior to populating the physmap and
>>> cancelling the claim at the end of the meminit() hook so this is never a 
>>> real
>>> problem.
>>>
>>> This tells me that the logic intent is to force early failure of
>>> populate_physmap and nothing else. It's never active by the time ballooning 
>>> or
>>> memory exchange matter at all.
>>
>> Ah yes, this I find more convincing. (Oddly enough this is all x86-only 
>> code.)
> 
> Should I take this as an "ack" to the general plan of early returning on pages
> <=0? I have a series pending that relies on it (the v2 of this[1]).

Not an ack, but an "I can accept this, but someone else will need to ack it".

Jan

> And would
> rather defer its sending until this one get some form of nod. Otherwise I'll
> integrate it in the other series so I can at least reduce remove dependencies
> between things in-flight.
> 
> Cheers,
> Alejandro
> 
> [1] 
> https://lore.kernel.org/xen-devel/20250304111000.9252-1-alejandro.vallejo@xxxxxxxxx/