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charset="UTF-8" X-Rspamd-Queue-Id: 47E0C6C05 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam01 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Sep 15, 2020 at 10:32 PM Matthew Wilcox wrote: > > On Tue, Sep 15, 2020 at 08:59:23PM +0800, Muchun Song wrote: > > This patch series will free some vmemmap pages(struct page structures) > > associated with each hugetlbpage when preallocated to save memory. > > It would be lovely to be able to do this. Unfortunately, it's completely > impossible right now. Consider, for example, get_user_pages() called > on the fifth page of a hugetlb page. Can you elaborate on the problem? Thanks so much. > > I've spent a lot of time thinking about this, and there's a lot of work > that needs to happen before we can do this, mostly in device drivers. > Do you want to help? It's a multi-year project. Welcome, we can work together. -- Yours, Muchun