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[209.85.221.49]) by smtp.gmail.com with ESMTPSA id h23-20020a1709060f5700b0073094d16ff2sm1828033ejj.14.2022.08.05.10.14.48 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 05 Aug 2022 10:14:48 -0700 (PDT) Received: by mail-wr1-f49.google.com with SMTP id l22so3929881wrz.7 for ; Fri, 05 Aug 2022 10:14:48 -0700 (PDT) X-Received: by 2002:a5d:5889:0:b0:21d:bccd:38e3 with SMTP id n9-20020a5d5889000000b0021dbccd38e3mr4797328wrf.659.1659719688007; Fri, 05 Aug 2022 10:14:48 -0700 (PDT) MIME-Version: 1.0 References: <20211116012912.723980-1-longman@redhat.com> <20220719104104.1634-1-hdanton@sina.com> <20220722115510.2101-1-hdanton@sina.com> <20220723001713.2156-1-hdanton@sina.com> In-Reply-To: <20220723001713.2156-1-hdanton@sina.com> From: Doug Anderson Date: Fri, 5 Aug 2022 10:14:36 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v5] locking/rwsem: Make handoff bit handling more consistent To: Hillf Danton Cc: Waiman Long , Peter Zijlstra , Will Deacon , Davidlohr Bueso , MM , LKML Content-Type: text/plain; charset="UTF-8" ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1659719692; a=rsa-sha256; cv=none; b=kMShB/cq14eNfDLWwapr0W5u+SNXtuNrhiG+bIGDneapAqbEr6nrao8FL7Pi8/6VeRIrcG h41nX9zVB+N8CdCaojn5rjn/lZ7dIExArzqpzCkg8AywqVEjaCB+8c0mWtTIW8hzP3YF8F iX8E9lGBpbPpGBpYQLaQSU5Fdflxt9U= ARC-Authentication-Results: i=1; imf06.hostedemail.com; dkim=pass header.d=chromium.org header.s=google header.b=e0NSP931; spf=pass (imf06.hostedemail.com: domain of dianders@chromium.org designates 209.85.218.49 as permitted sender) smtp.mailfrom=dianders@chromium.org; dmarc=pass (policy=none) header.from=chromium.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1659719692; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=pFJxvp8fwyz1vgCPNQyO0NCG68skXsENlZHLzqZoSXM=; b=hw0HJj92Y4B9KILnwdsk0GCw/Kd2sPAbQcOeTD3i10r0V5sItFhoH7AVj2mpixPWngGMaE G9yABmpuPG5NZlCgy+iJZft3wJRxNZCLQmiiiHMpuNqCZhVahD5iS83quk1ClquaP1EIA7 MAVYHbdWabyJh6l2g9Lif9wx7/WB9wM= X-Rspam-User: X-Stat-Signature: iisxdc61f85sxkkbbmu8rsrj3ctqowj5 X-Rspamd-Queue-Id: A626D180129 Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=chromium.org header.s=google header.b=e0NSP931; spf=pass (imf06.hostedemail.com: domain of dianders@chromium.org designates 209.85.218.49 as permitted sender) smtp.mailfrom=dianders@chromium.org; dmarc=pass (policy=none) header.from=chromium.org X-Rspamd-Server: rspam02 X-HE-Tag: 1659719691-435878 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: Hi, On Fri, Jul 22, 2022 at 5:17 PM Hillf Danton wrote: > > On Fri, 22 Jul 2022 07:02:42 -0700 Doug Anderson wrote: > > > > Thanks! I added this diff to your previous diff and my simple test > > still passes and I don't see your WARN_ON triggered. > > Thanks! > > > > How do we move forward? Are you going to officially submit a patch > > with both of your diffs squashed together? Are we waiting for > > additional review from someone? > > Given it is not unusual for us to miss anything important, lets take > a RWSEM_WAIT_TIMEOUT nap now or two. It appears that another fix has landed in the meantime. Commit 6eebd5fb2083 ("locking/rwsem: Allow slowpath writer to ignore handoff bit if not set by first waiter"). ...unfortunately with that patch my test cases still hangs. :(