Messages in this thread | | | Date | Sun, 14 Dec 2014 18:08:09 -0500 | From | Benjamin LaHaise <> | Subject | Re: [GIT PULL] aio: changes for 3.19 |
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On Mon, Dec 15, 2014 at 01:02:08AM +0200, Kirill A. Shutemov wrote: > But it seems the problem is bigger than what the patch fixes. To me we are > too permisive on what vma can be remapped. > > How can we know that it's okay to move vma around for random driver which > provide .mmap? Or I miss something obvious?
Most drivers do not care if a vma is moved within the virtual address space of a process. The aio ring buffer is special in that it gets unmapped when userspace does an io_destroy(), and io_destroy() has to know what the address is moved to in order to perform the unmap. Normal drivers don't perform the unmap themselves.
-ben -- "Thought is the essence of where you are now."
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