12 Jul
2018
12 Jul
'18
4:39 p.m.
On Thu, Jul 12, 2018 at 06:20:39PM +0200, Oleg Nesterov wrote:
Kirill, I am not trying to review this change (but it looks good to me), just a silly question...
On 07/12, Kirill A. Shutemov wrote:
This can be fixed by assigning anonymous VMAs own vm_ops and not relying on it being NULL.
I agree, this makes sense, but...
If ->mmap() failed to set ->vm_ops, mmap_region() will set it to dummy_vm_ops.
Shouldn't this change alone fix the problem?
Unfortunately, no. I've tried it before. Mapping /dev/zero with MAP_PRIVATE hast to produce anonymous VMA. The trick with dummy_vm_ops wouldn't be able to handle the situation.
--
Kirill A. Shutemov