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[173.76.246.42]) by smtp.gmail.com with ESMTPSA id h52sm3711686qte.78.2019.03.07.10.46.17 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 07 Mar 2019 10:46:18 -0800 (PST) Date: Thu, 7 Mar 2019 13:46:16 -0500 From: "Michael S. Tsirkin" To: Alexander Duyck Cc: Nitesh Narayan Lal , kvm list , LKML , linux-mm , Paolo Bonzini , lcapitulino@redhat.com, pagupta@redhat.com, wei.w.wang@intel.com, Yang Zhang , Rik van Riel , David Hildenbrand , dodgen@google.com, Konrad Rzeszutek Wilk , dhildenb@redhat.com, Andrea Arcangeli Subject: Re: [RFC][Patch v9 0/6] KVM: Guest Free Page Hinting Message-ID: <20190307134455-mutt-send-email-mst@kernel.org> References: <20190306155048.12868-1-nitesh@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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 Wed, Mar 06, 2019 at 10:00:05AM -0800, Alexander Duyck wrote: > I have been thinking about this. Instead of stealing the page couldn't > you simply flag it that there is a hint in progress and simply wait in > arch_alloc_page until the hint has been processed? The problem is in > stealing pages you are going to introduce false OOM issues when the > memory isn't available because it is being hinted on. Can we not give them back in an OOM notifier? -- MST