From 9fc33eaaa979d112d10fea729edcd2a2e21aa912 Mon Sep 17 00:00:00 2001
From: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Date: Thu, 30 Jun 2022 23:06:01 +0300
Subject: [PATCH] drm/panfrost: Fix shrinker list corruption by madvise IOCTL
Calling madvise IOCTL twice on BO causes memory shrinker list corruption
and crashes kernel because BO is already on the list and it's added to
the list again, while BO should be removed from the list before it's
re-added. Fix it.
Cc: stable@vger.kernel.org
Fixes: 013b65101315 ("drm/panfrost: Add madvise and shrinker support")
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220630200601.1884120-3-dmitry.osipenko@collabora.com
---
drivers/gpu/drm/panfrost/panfrost_drv.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c
index 087e69b98d069..b1e6d238674ff 100644
--- a/drivers/gpu/drm/panfrost/panfrost_drv.c
+++ b/drivers/gpu/drm/panfrost/panfrost_drv.c
@@ -433,8 +433,8 @@ static int panfrost_ioctl_madvise(struct drm_device *dev, void *data,
if (args->retained) {
if (args->madv == PANFROST_MADV_DONTNEED)
- list_add_tail(&bo->base.madv_list,
- &pfdev->shrinker_list);
+ list_move_tail(&bo->base.madv_list,
+ &pfdev->shrinker_list);
else if (args->madv == PANFROST_MADV_WILLNEED)
list_del_init(&bo->base.madv_list);
}