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[82.17.115.77]) by smtp.gmail.com with ESMTPSA id l8sm7695747wrw.56.2019.05.16.09.29.46 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 16 May 2019 09:29:47 -0700 (PDT) Date: Thu, 16 May 2019 17:29:46 +0100 From: Aaron Tomlin To: Jann Horn Cc: Oleksandr Natalenko , kernel list , Kirill Tkhai , Hugh Dickins , Alexey Dobriyan , Vlastimil Babka , Michal Hocko , Matthew Wilcox , Pavel Tatashin , Greg KH , Suren Baghdasaryan , Minchan Kim , Timofey Titovets , Grzegorz Halat , Linux-MM , Linux API Subject: Re: [PATCH RFC 4/5] mm/ksm, proc: introduce remote merge Message-ID: <20190516162946.zwzhxkft342b25pd@atomlin.usersys.com> References: <20190516094234.9116-1-oleksandr@redhat.com> <20190516094234.9116-5-oleksandr@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-PGP-Key: http://pgp.mit.edu/pks/lookup?search=atomlin%40redhat.com X-PGP-Fingerprint: 7906 84EB FA8A 9638 8D1E 6E9B E2DE 9658 19CC 77D6 User-Agent: NeoMutt/20180716-1637-ee8449 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 Thu 2019-05-16 12:00 +0200, Jann Horn wrote: > On Thu, May 16, 2019 at 11:43 AM Oleksandr Natalenko > wrote: [ ... ] > > + } > > + > > + down_write(&mm->mmap_sem); > > Should a check for mmget_still_valid(mm) be inserted here? See commit > 04f5866e41fb70690e28397487d8bd8eea7d712a. Yes - I'd say this is required here. Thanks, -- Aaron Tomlin