From: Aric Cyr <[email protected]> [why] In some cases MPC tree bottom pipe ends up point to itself. This causes iterating from top to bottom to hang the system in an infinite loop.
[how] When looping to next MPC bottom pipe, check that the pointer is not same as current to avoid infinite loop. Reviewed-by: Josip Pavic <[email protected]> Reviewed-by: Jun Lei <[email protected]> Acked-by: Alex Hung <[email protected]> Signed-off-by: Aric Cyr <[email protected]> --- drivers/gpu/drm/amd/display/dc/dcn10/dcn10_mpc.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_mpc.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_mpc.c index 11019c2c62cc..769974375b4b 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_mpc.c +++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_mpc.c @@ -49,6 +49,11 @@ void mpc1_set_bg_color(struct mpc *mpc, /* find bottommost mpcc. */ while (bottommost_mpcc->mpcc_bot) { + /* avoid circular linked link */ + ASSERT(bottommost_mpcc != bottommost_mpcc->mpcc_bot); + if (bottommost_mpcc == bottommost_mpcc->mpcc_bot) + break; + bottommost_mpcc = bottommost_mpcc->mpcc_bot; } -- 2.37.1
