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Shutemov" To: Matthew Wilcox Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Will Deacon , Catalin Marinas , Russell King , Geert Uytterhoeven , linux-m68k@lists.linux-m68k.org Subject: Re: [PATCH 0/7] Record the mm_struct in the page table pages Message-ID: <20200429002624.qkhb362moj6v3vtw@box> References: <20200428194449.22615-1-willy@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200428194449.22615-1-willy@infradead.org> 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, Apr 28, 2020 at 12:44:42PM -0700, Matthew Wilcox wrote: > From: "Matthew Wilcox (Oracle)" > > Pages which are in use as page tables have some space unused in struct > page. It would be handy to have a pointer to the struct mm_struct that > they belong to so that we can handle uncorrectable errors in page tables > more gracefully. There are a few other things we could use it for too, > such as checking that the page table entry actually belongs to the task > we think it ought to. This patch series does none of that, but does > lay the groundwork for it. > > Matthew Wilcox (Oracle) (7): How does it work for kernel side of virtual address space? And your employer may be interested in semantics around CONFIG_ARCH_WANT_HUGE_PMD_SHARE :P -- Kirill A. Shutemov