On 8/3/26 14:41, Timur Kristóf wrote:
> The pipe_ctx->plane_res.hubp pointer is NULL on all DCE
> hardware, which causes a kernel NULL pointer dereference
> on all Vega and older GPUs.
>
> Let's add a simple NULL check.
>
> Fixes: f879f53407f0 ("drm/amd/display: Refactor DPP_SET_OUTPUT_TRANSFER_FUNC
> to drop pipe_ctx")
> Signed-off-by: Timur Kristóf <[email protected]>
> Cc: Tomasz Siemek <[email protected]>
I've tested this patch (applied to amd-staging-drm-next) because I
observed the crash during my tests for
https://gitlab.freedesktop.org/drm/amd/-/work_items/5557 and I confirm
that the patch fixes the crash.
Tested-by: Viktor Jägersküpper <[email protected]>
> ---
> drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c
> b/drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c
> index 11411fa94665..5495e493b2eb 100644
> --- a/drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c
> +++ b/drivers/gpu/drm/amd/display/dc/core/dc_hw_sequencer.c
> @@ -1900,7 +1900,8 @@ void hwss_set_output_transfer_func(struct dc *dc,
> struct pipe_ctx *pipe_ctx)
> .xfm = pipe_ctx->plane_res.xfm,
> .dpp = pipe_ctx->plane_res.dpp,
> .mpc = dc->res_pool->mpc,
> - .mpcc_id = pipe_ctx->plane_res.hubp->inst,
> + .mpcc_id = pipe_ctx->plane_res.hubp ?
> + pipe_ctx->plane_res.hubp->inst
> : 0,
> .is_top_pipe = resource_is_pipe_type(pipe_ctx,
> OPP_HEAD),
> .stream = pipe_ctx->stream,
> }
