From 6ed0897cd800c38b92a33d335d9086c7b092eb15 Mon Sep 17 00:00:00 2001 From: Rob Clark Date: Wed, 31 Mar 2021 18:27:20 -0700 Subject: drm/msm: Fix debugfs deadlock In normal cases the gem obj lock is acquired first before mm_lock. The exception is iterating the various object lists. In the shrinker path, deadlock is avoided by using msm_gem_trylock() and skipping over objects that cannot be locked. But for debugfs the straightforward thing is to split things out into a separate list of all objects protected by it's own lock. Fixes: d984457b31c4 ("drm/msm: Add priv->mm_lock to protect active/inactive lists") Signed-off-by: Rob Clark Tested-by: Douglas Anderson Reviewed-by: Douglas Anderson Link: https://lore.kernel.org/r/20210401012722.527712-4-robdclark@gmail.com Signed-off-by: Rob Clark --- drivers/gpu/drm/msm/msm_debugfs.c | 14 +++----------- 1 file changed, 3 insertions(+), 11 deletions(-) (limited to 'drivers/gpu/drm/msm/msm_debugfs.c') diff --git a/drivers/gpu/drm/msm/msm_debugfs.c b/drivers/gpu/drm/msm/msm_debugfs.c index 85ad0babc326..d611cc8e54a4 100644 --- a/drivers/gpu/drm/msm/msm_debugfs.c +++ b/drivers/gpu/drm/msm/msm_debugfs.c @@ -111,23 +111,15 @@ static const struct file_operations msm_gpu_fops = { static int msm_gem_show(struct drm_device *dev, struct seq_file *m) { struct msm_drm_private *priv = dev->dev_private; - struct msm_gpu *gpu = priv->gpu; int ret; - ret = mutex_lock_interruptible(&priv->mm_lock); + ret = mutex_lock_interruptible(&priv->obj_lock); if (ret) return ret; - if (gpu) { - seq_printf(m, "Active Objects (%s):\n", gpu->name); - msm_gem_describe_objects(&gpu->active_list, m); - } - - seq_printf(m, "Inactive Objects:\n"); - msm_gem_describe_objects(&priv->inactive_dontneed, m); - msm_gem_describe_objects(&priv->inactive_willneed, m); + msm_gem_describe_objects(&priv->objects, m); - mutex_unlock(&priv->mm_lock); + mutex_unlock(&priv->obj_lock); return 0; } -- cgit