From 3b401e30c249849d803de6c332dad2a595a58658 Mon Sep 17 00:00:00 2001
From: Karolina Stolarek <karolina.stolarek@intel.com>
Date: Mon, 16 Oct 2023 14:15:25 +0200
Subject: [PATCH] drm/ttm: Reorder sys manager cleanup step
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Git-commit: 3b401e30c249849d803de6c332dad2a595a58658
Patch-mainline: v6.6-rc7
References: git-fixes
With the current cleanup flow, we could trigger a NULL pointer
dereference if there is a delayed destruction of a BO with a
system resource that gets executed on drain_workqueue() call,
as we attempt to free a resource using an already released
resource manager.
Remove the device from the device list and drain its workqueue
before releasing the system domain manager in ttm_device_fini().
Signed-off-by: Karolina Stolarek <karolina.stolarek@intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231016121525.2237838-1-karolina.stolarek@intel.com
Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/ttm/ttm_device.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/gpu/drm/ttm/ttm_device.c
+++ b/drivers/gpu/drm/ttm/ttm_device.c
@@ -239,10 +239,6 @@ void ttm_device_fini(struct ttm_device *
struct ttm_resource_manager *man;
unsigned i;
- man = ttm_manager_type(bdev, TTM_PL_SYSTEM);
- ttm_resource_manager_set_used(man, false);
- ttm_set_driver_manager(bdev, TTM_PL_SYSTEM, NULL);
-
mutex_lock(&ttm_global_mutex);
list_del(&bdev->device_list);
mutex_unlock(&ttm_global_mutex);
@@ -252,6 +248,10 @@ void ttm_device_fini(struct ttm_device *
if (ttm_bo_delayed_delete(bdev, true))
pr_debug("Delayed destroy list was clean\n");
+ man = ttm_manager_type(bdev, TTM_PL_SYSTEM);
+ ttm_resource_manager_set_used(man, false);
+ ttm_set_driver_manager(bdev, TTM_PL_SYSTEM, NULL);
+
spin_lock(&bdev->lru_lock);
for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
if (list_empty(&man->lru[0]))