Re: mmaping a kernel buffer to user space



Hi,

Jiri Slaby wrote:
Guillermo Marcus wrote:
Hi Jiri,

The fact that it does not works with RAM is well documented in LDD3,
pages 430++. It says (and I tested) that remap_xxx_range does not work
in this case. They suggest a method using nopage, similar to the one I
implement.

Could somebody confirm, that this still holds?

Apparently this restriction has been removed since 2.6.15 when
VM_PFNMAP flag has been introduced, see commit
6aab341e0a28aff100a09831c5300a2994b8b986

Why there's such restriction before 2.6.15, I haven't searched
yet, but any hints would be appreciated.

Thanks
Franck
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