Re: [PATCH v4 0/5] implement lightweight guard pages

[SeongJae Park]

On Mon, 28 Oct 2024 14:13:26 +0000 Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx> wrote:

> Userland library functions such as allocators and threading implementations
> often require regions of memory to act as 'guard pages' - mappings which,
> when accessed, result in a fatal signal being sent to the accessing
> process.
> 
> The current means by which these are implemented is via a PROT_NONE mmap()
> mapping, which provides the required semantics however incur an overhead of
> a VMA for each such region.
> 
> With a great many processes and threads, this can rapidly add up and incur
> a significant memory penalty. It also has the added problem of preventing
> merges that might otherwise be permitted.
> 
> This series takes a different approach - an idea suggested by Vlasimil
> Babka (and before him David Hildenbrand and Jann Horn - perhaps more - the

Nit.  s/Vlasimil/Vlastimil/ ;)


Thanks,
SJ

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