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| author | Zack Rusin <zackr@vmware.com> | 2022-12-07 20:29:07 +0300 |
|---|---|---|
| committer | Zack Rusin <zackr@vmware.com> | 2023-01-10 05:15:36 +0300 |
| commit | a309c7194e8a2f8bd4539b9449917913f6c2cd50 (patch) | |
| tree | 2774c49f4f5f962fd9271533104b293bd1031aad /drivers/gpu/drm/vmwgfx/vmwgfx_resource.c | |
| parent | 52531258318ed59a2dc5a43df2eaf0eb1d65438e (diff) | |
| download | linux-a309c7194e8a2f8bd4539b9449917913f6c2cd50.tar.xz | |
drm/vmwgfx: Remove rcu locks from user resources
User resource lookups used rcu to avoid two extra atomics. Unfortunately
the rcu paths were buggy and it was easy to make the driver crash by
submitting command buffers from two different threads. Because the
lookups never show up in performance profiles replace them with a
regular spin lock which fixes the races in accesses to those shared
resources.
Fixes kernel oops'es in IGT's vmwgfx execution_buffer stress test and
seen crashes with apps using shared resources.
Fixes: e14c02e6b699 ("drm/vmwgfx: Look up objects without taking a reference")
Signed-off-by: Zack Rusin <zackr@vmware.com>
Reviewed-by: Martin Krastev <krastevm@vmware.com>
Reviewed-by: Maaz Mombasawala <mombasawalam@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221207172907.959037-1-zack@kde.org
Diffstat (limited to 'drivers/gpu/drm/vmwgfx/vmwgfx_resource.c')
| -rw-r--r-- | drivers/gpu/drm/vmwgfx/vmwgfx_resource.c | 33 |
1 files changed, 0 insertions, 33 deletions
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c index f66caa540e14..c7d645e5ec7b 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c @@ -281,39 +281,6 @@ out_bad_resource: return ret; } -/** - * vmw_user_resource_noref_lookup_handle - lookup a struct resource from a - * TTM user-space handle and perform basic type checks - * - * @dev_priv: Pointer to a device private struct - * @tfile: Pointer to a struct ttm_object_file identifying the caller - * @handle: The TTM user-space handle - * @converter: Pointer to an object describing the resource type - * - * If the handle can't be found or is associated with an incorrect resource - * type, -EINVAL will be returned. - */ -struct vmw_resource * -vmw_user_resource_noref_lookup_handle(struct vmw_private *dev_priv, - struct ttm_object_file *tfile, - uint32_t handle, - const struct vmw_user_resource_conv - *converter) -{ - struct ttm_base_object *base; - - base = ttm_base_object_noref_lookup(tfile, handle); - if (!base) - return ERR_PTR(-ESRCH); - - if (unlikely(ttm_base_object_type(base) != converter->object_type)) { - ttm_base_object_noref_release(); - return ERR_PTR(-EINVAL); - } - - return converter->base_obj_to_res(base); -} - /* * Helper function that looks either a surface or bo. * |