[Qemu-devel] Re: [PATCH 01/32] use anonymous memory for kqemu.

[Jan Kiszka <jan.kiszka@siemens.com>]

Anthony Liguori wrote:
> The idea behind this patch is that currently kqemu uses /dev/shm for
> memory allocations instead of anonymous memory (like the rest of QEMU). 
> Instead of introducing YA hook, we can just switch kqemu to use
> anonymous memory and eliminate the special case.
> 
> If I recall correctly, the reason for using /dev/shm was concern that
> get_user_pages() didn't do the right thing for anonymous memory and the
> use of /dev/shm was a hack around that.  However, I'm not sure that was
> ever the case.  Certainly, with any sufficiently modern kernel
> get_user_pages() does what one would expect.  KVM uses get_user_pages()
> on anonymous memory in roughly the same way kqemu uses it now.
> 
> So I think it's safe to make the switch.  Fabrice, what do you think?

This hack-around, was it purely Linux-motivated? Or did/do other OSes
have similar issues?

Jan

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