Hello Jack Chang,
Commit 74ce00932e7e ("drm/amd/display: Refactor panel replay set dmub
cmd flow") from Sep 3, 2025 (linux-next), leads to the following
Smatch static checker warning:
drivers/gpu/drm/amd/amdgpu/../display/dc/link/protocols/link_edp_panel_control.c:1459
edp_pr_get_state()
warn: passing casted pointer 'state' to 'dc_wake_and_execute_gpint()'
64 vs 32.
drivers/gpu/drm/amd/amdgpu/../display/dc/link/protocols/link_edp_panel_control.c
1448 bool edp_pr_get_state(const struct dc_link *link, uint64_t *state)
^^^^^^^^^^^^^^^
1449 {
1450 const struct dc *dc = link->ctx->dc;
1451 unsigned int panel_inst = 0;
1452 uint32_t retry_count = 0;
1453
1454 if (!dc_get_edp_link_panel_inst(dc, link, &panel_inst))
1455 return false;
1456
1457 do {
1458 // Send gpint command and wait for ack
--> 1459 if (!dc_wake_and_execute_gpint(dc->ctx,
DMUB_GPINT__GET_REPLAY_STATE, panel_inst,
1460 (uint32_t *)state,
DM_DMUB_WAIT_TYPE_WAIT_WITH_REPLY)) {
^^^^^^^^^^^^^^^^^
The dc_wake_and_execute_gpint() function doesn't take a u64, it takes
a u32. It tries to initialize the state to zero at the start but
that's not going to work because of the type mismatch. It suggests
that callers are allowed to pass uninitialized data to
edp_pr_get_state() but at present there are no callers so this is
only a bug in the code but doesn't affect runtime.
1461 // Return invalid state when GPINT times out
1462 *state = PR_STATE_INVALID;
1463 }
1464 } while (++retry_count <= 1000 && *state == PR_STATE_INVALID);
1465
1466 // Assert if max retry hit
1467 if (retry_count >= 1000 && *state == PR_STATE_INVALID) {
1468 ASSERT(0);
1469 /* To-do: Add retry fail log */
1470 }
1471
1472 return true;
1473 }
regards,
dan carpenter
