| Message ID | 20221110094445.2930509-6-cuigaosheng1@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fix IS_ERR() vs NULL check for drm | expand |
On Thu, 10 Nov 2022 17:44:45 +0800, Gaosheng Cui wrote: > The drm_atomic_get_new_private_obj_state() function returns NULL > on error path, drm_atomic_get_old_private_obj_state() function > returns NULL on error path, too, they does not return error pointers. > > By the way, vc4_hvs_get_new/old_global_state() should return > ERR_PTR(-EINVAL), otherwise there will be null-ptr-defer issue, > such as follows: > > [...] Applied to drm/drm-misc (drm-misc-fixes). Thanks! Maxime
diff --git a/drivers/gpu/drm/vc4/vc4_kms.c b/drivers/gpu/drm/vc4/vc4_kms.c index 5c97642ed66a..8fbeecdf2ec4 100644 --- a/drivers/gpu/drm/vc4/vc4_kms.c +++ b/drivers/gpu/drm/vc4/vc4_kms.c @@ -197,8 +197,8 @@ vc4_hvs_get_new_global_state(struct drm_atomic_state *state) struct drm_private_state *priv_state; priv_state = drm_atomic_get_new_private_obj_state(state, &vc4->hvs_channels); - if (IS_ERR(priv_state)) - return ERR_CAST(priv_state); + if (!priv_state) + return ERR_PTR(-EINVAL); return to_vc4_hvs_state(priv_state); } @@ -210,8 +210,8 @@ vc4_hvs_get_old_global_state(struct drm_atomic_state *state) struct drm_private_state *priv_state; priv_state = drm_atomic_get_old_private_obj_state(state, &vc4->hvs_channels); - if (IS_ERR(priv_state)) - return ERR_CAST(priv_state); + if (!priv_state) + return ERR_PTR(-EINVAL); return to_vc4_hvs_state(priv_state); }
The drm_atomic_get_new_private_obj_state() function returns NULL on error path, drm_atomic_get_old_private_obj_state() function returns NULL on error path, too, they does not return error pointers. By the way, vc4_hvs_get_new/old_global_state() should return ERR_PTR(-EINVAL), otherwise there will be null-ptr-defer issue, such as follows: In function vc4_atomic_commit_tail(): |-- old_hvs_state = vc4_hvs_get_old_global_state(state); <-- return NULL |-- if (WARN_ON(IS_ERR(old_hvs_state))) <-- no return |-- unsigned long state_rate = max(old_hvs_state->core_clock_rate, new_hvs_state->core_clock_rate); <-- null-ptr-defer Fixes: 9ec03d7f1ed3 ("drm/vc4: kms: Wait on previous FIFO users before a commit") Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com> --- drivers/gpu/drm/vc4/vc4_kms.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)