On 04/25/2018 09:04 AM, Matthew Wilcox wrote:
> If you don't zap the page range, any of the CPUs in the system where > any thread in this task have ever run may have a TLB entry pointing to > this page ... if the page is being recycled into the page allocator, > then that page might end up as a slab page or page table or page cache > while the other CPU still have access to it. Yes, this makes sense. > > You could hang onto the page until you've built up a sufficiently large > batch, then bulk-invalidate all of the TLB entries, but we start to get > into weirdnesses on different CPU architectures. > zap_page_range() is already doing a bulk-invalidate, so maybe vm_replace_page() wont bring serious improvement if we end-up doing same dance. Thanks.
