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Date:   Thu, 14 Sep 2023 15:30:41 +0200
From:   Boris Brezillon <boris.brezillon@collabora.com>
To:     Dmitry Osipenko <dmitry.osipenko@collabora.com>
Cc:     David Airlie <airlied@gmail.com>,
        Gerd Hoffmann <kraxel@redhat.com>,
        Gurchetan Singh <gurchetansingh@chromium.org>,
        Chia-I Wu <olvaffe@gmail.com>, Daniel Vetter <daniel@ffwll.ch>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        Christian =?UTF-8?B?S8O2bmln?= <christian.koenig@amd.com>,
        Qiang Yu <yuq825@gmail.com>,
        Steven Price <steven.price@arm.com>,
        Emma Anholt <emma@anholt.net>, Melissa Wen <mwen@igalia.com>,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        kernel@collabora.com, virtualization@lists.linux-foundation.org
Subject: Re: [PATCH v16 15/20] drm/shmem-helper: Add memory shrinker
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On Thu, 14 Sep 2023 15:27:03 +0200
Boris Brezillon <boris.brezillon@collabora.com> wrote:

> You should drop the '&& refcount_read(&shmem->pages_use_count)',
> otherwise you'll never enter this branch (sgt allocation retained
> a ref, so pages_use_count > 0 when ->sgt != NULL).

Sorry for the brain fart. You can drop this extra test because its
redundant (->sgt != NULL implies pages_use_count > 0), but it shouldn't
prevent you from entering the branch.