Re: [PATCH] - gnumach: Implement offset in device map

[Samuel Thibault]

Hello,

Thanks for your patches, they were way better, I have applied them!

Joan Lledó, le sam. 28 août 2021 12:02:50 +0200, a ecrit:
> I tried to insert the same dev_pager_entry in both lists to avoid 
> duplication, but the links field can't be shared between two lists,

Mmm, I think you can, by using another links field?

> I also created the equivalent to dev_device_hash[init,insert,delete,lookup] 
> functions for the devices hash,

I guess that was necessary anyway, since they're not accessing the same
table and the same lists.

> then dev_pager_setup will find it in the hash and return a name for the same 
> pager, so two tasks are sharing the pager, is not that a security problem?

Actually we do want this: for memory writes/reads/swapout/swapin to be
coherent, it has to be managed by the same pager behind.

> > adding to gnu mach a function that returns a memory proxy for a given range 
> > of memory, that would also make a lot of sense
> 
> If you think it's safe to return a pager belonging to the same task who 
> requested it, then I'll do it.

I believe so: it's the same memory object in the end.

Samuel