Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
Pre-existing issues: - [High] Integer underflow when computing MST.slotEnd for disabled outputs, leading to a massive slotEnd value (0xFFFFFFFF). -- --- Patch [4]: [PATCH 4/7] nouveau/gsp: use per-version DP_CONFIG_STREAM params on r570 firmware --- commit d855125b895d27bafd2aaed0c330ae6eae007aef Author: Mohamed Ahmed <[email protected]> nouveau/gsp: use per-version DP_CONFIG_STREAM params on r570 firmware This commit separates the DP_CONFIG_STREAM_PARAMS structure and its related functions into r535 and r570 variants. This handles the structure shrinking that occurred in the 570 firmware version. > diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r570/disp.c > b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r570/disp.c > index a96e31c2d80b2..61f82e15ff398 100644 > --- a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r570/disp.c > +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r570/disp.c [ ... ] > @@ -74,6 +75,67 @@ r570_disp_chan_set_pushbuf(struct nvkm_disp *disp, s32 > oclass, int inst, struct > return nvkm_gsp_rm_ctrl_wr(&gsp->internal.device.subdevice, ctrl); > } > > +static void > +r570_dp_vcpi(struct nvkm_ior *sor, int head, u8 slot, u8 slot_nr, u16 pbn, > u16 aligned_pbn) > +{ > + struct nvkm_disp *disp = sor->disp; > + NV0073_CTRL_CMD_DP_CONFIG_STREAM_PARAMS *ctrl; [ ... ] > + ctrl->MST.slotStart = slot; > + ctrl->MST.slotEnd = slot + slot_nr - 1; [Severity: High] This isn't a bug introduced by this patch, but this preexisting issue gets copied into the new r570_dp_vcpi() function from the r535 code. When an MST output is disabled, nv50_msto_prepare() (in dispnv50/disp.c) calls nvif_outp_dp_mst_vcpi() with num_slots=0. This propagates here, setting slot_nr to 0. With slot_nr = 0, does the expression "slot + slot_nr - 1" evaluate to -1? Since MST.slotEnd is an NvU32, this would underflow to 0xFFFFFFFF, passing a maximal bound for a time slot range to the GSP firmware. Could this potentially cause out-of-bounds accesses or hangs in the firmware? Should this logic be updated to handle slot_nr = 0 safely before it evaluates to -1 and underflows? > + ctrl->MST.PBN = pbn; -- Sashiko AI review ยท https://sashiko.dev/#/patchset/[email protected]?part=4
