Re: Hinted mmap(2) without MAP_FIXED can fail prematurely

[Johnny Billquist <bqt%softjar.se@localhost>]

If it would ignore the hint, what's the point of the hint then?

  Johnny

On 2022-02-17 08:23, PHO wrote:
> I'm not sure if this is a bug or not, but on NetBSD/amd64 9.2, hinted 
> mmap(2) without MAP_FIXED can fail prematurely with ENOMEM if all the 
> regions below the given hint address are occupied.
>
> The man page for mmap(2) suggests that the hint is just a hint. 
> Shouldn't mmap(2) also search for available regions above the hint then?
>
> Test code:
> https://gist.github.com/depressed-pho/a629247b48b3e6178e35a14c62e9d44f#file-mmap-with-hint-c 
>
>
> Test result:
> https://gist.github.com/depressed-pho/a629247b48b3e6178e35a14c62e9d44f#file-gistfile1-txt 

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Johnny Billquist                  || "I'm on a bus
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