From mboxrd@z Thu Jan 1 00:00:00 1970 From: KOSAKI Motohiro Subject: Re: [RFC][PATCH v3 1/6] mm: Don't unmap gup()ed page Date: Wed, 15 Apr 2009 20:53:11 +0900 Message-ID: <2f11576a0904150453g4332e0d5h5bcad97fac7af24@mail.gmail.com> References: <20090414143252.GE28265@random.random> <200904150042.15653.nickpiggin@yahoo.com.au> <20090415165431.AC4C.A69D9226@jp.fujitsu.com> <20090415104615.GG9809@random.random> <2f11576a0904150439k6e828307ja97b6729650bcb94@mail.gmail.com> <20090415114154.GI9809@random.random> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Nick Piggin , LKML , Linus Torvalds , Andrew Morton , Jeff Moyer , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Hugh Dickins To: Andrea Arcangeli Return-path: In-Reply-To: <20090415114154.GI9809@random.random> Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org >> Can we assume mmu_notifier is only used by kvm now? >> if not, we need to make new notifier. > > KVM is no fundamentally different from other users in this respect, so > I don't see why need a new notifier. If it works for others it'll work > for KVM and the other way around is true too. > > mmu notifier users can or cannot take a page pin. KVM does. GRU > doesn't. XPMEM does. All of them releases any pin after > mmu_notifier_invalidate_page. All that is important is to run > mmu_notifier_invalidate_page _after_ the ptep_clear_young_notify, so > that we don't nuke secondary mappings on the pages unless we really go > to nuke the pte. Thank you kindful explain. I understand it :) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org