Re: [PATCH RFC] mm/madvise: introduce MADV_POPULATE to prefault/prealloc memory

[David Hildenbrand]

> Am 18.02.2021 um 12:15 schrieb Rolf Eike Beer <eike-kernel@xxxxxxxxx>:
> 
> 
>> 
>>> Let's introduce MADV_POPULATE with the following semantics
>>> 1. MADV_POPULATED does not work on PROT_NONE and special VMAs. It works
>>>   on everything else.
>>> 2. Errors during MADV_POPULATED (especially OOM) are reported. If we hit
>>>   hardware errors on pages, ignore them - nothing we really can or
>>>   should do.
>>> 3. On errors during MADV_POPULATED, some memory might have been
>>>   populated. Callers have to clean up if they care.
>>> 4. Concurrent changes to the virtual memory layour are tolerated - we
>                                                    ^t
>>>   process each and every PFN only once, though.
>>> 5. If MADV_POPULATE succeeds, all memory in the range can be accessed
>>>   without SIGBUS. (of course, not if user space changed mappings in the
>>>   meantime or KSM kicked in on anonymous memory).
> 
> You are talking both about MADV_POPULATE and MADV_POPULATED here.
> 

Already fixed up :) thanks!

> Eike
>