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[209.85.167.45]) by smtp.gmail.com with ESMTPSA id c145sm3227922lfd.52.2020.07.23.12.03.20 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 23 Jul 2020 12:03:20 -0700 (PDT) Received: by mail-lf1-f45.google.com with SMTP id s9so3872559lfs.4 for ; Thu, 23 Jul 2020 12:03:20 -0700 (PDT) X-Received: by 2002:a05:6512:241:: with SMTP id b1mr2969280lfo.125.1595531000293; Thu, 23 Jul 2020 12:03:20 -0700 (PDT) MIME-Version: 1.0 References: <20200721063258.17140-1-mhocko@kernel.org> <20200723124749.GA7428@redhat.com> <20200723180100.GA21755@redhat.com> In-Reply-To: From: Linus Torvalds Date: Thu, 23 Jul 2020 12:03:03 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [RFC PATCH] mm: silence soft lockups from unlock_page To: Oleg Nesterov Cc: Hugh Dickins , Michal Hocko , Linux-MM , LKML , Andrew Morton , Tim Chen , Michal Hocko Content-Type: multipart/mixed; boundary="000000000000805f8005ab208298" X-Rspamd-Queue-Id: B651D14DB5 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam05 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: --000000000000805f8005ab208298 Content-Type: text/plain; charset="UTF-8" On Thu, Jul 23, 2020 at 11:22 AM Linus Torvalds wrote: > > So I think that is a separate issue, generic to our finish_wait() uses. IOW, I think we should do something like this (this is on top of my patch, since it has that wake_page_function() change in it, but notice how we have the exact same issue in our traditional autoremove_wake_function() usage). Comments? 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