1VM_UNMAP_ALIASES(9) Memory Management in Linux VM_UNMAP_ALIASES(9)
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6 vm_unmap_aliases - unmap outstanding lazy aliases in the vmap layer
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9 void vm_unmap_aliases(void);
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12 void
13 no arguments
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16 The vmap/vmalloc layer lazily flushes kernel virtual mappings primarily
17 to amortize TLB flushing overheads. What this means is that any page
18 you have now, may, in a former life, have been mapped into kernel
19 virtual address by the vmap layer and so there might be some CPUs with
20 TLB entries still referencing that page (additional to the regular 1:1
21 kernel mapping).
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23 vm_unmap_aliases flushes all such lazy mappings. After it returns, we
24 can be sure that none of the pages we have control over will have any
25 aliases from the vmap layer.
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28Kernel Hackers Manual 2.6. June 2019 VM_UNMAP_ALIASES(9)