vgsp: RUSD INIT_USER_SHARED_DATA (0x20800afe) handler + gsp-phys-shared-bit0 knob - direct client channel alloc gate broken open (c46f hObject=0xbeef0101, err@ReadPixels=0x0 px=255,0,255,0) - SESSION 153 r999-r1002HEADmaster

1 files changed, 36 insertions, 0 deletions

diff --git a/kernel/gsp_rm_emulation.c b/kernel/gsp_rm_emulation.c
index 653ff1d..2f63bcd 100644
--- a/kernel/gsp_rm_emulation.c
+++ b/kernel/gsp_rm_emulation.c
@@ -4412,6 +4412,42 @@ static void gsp_rm_handle_rm_control(struct gsp_emu_context *ctx,
 		break;
 	}
 
+	case 0x20800afe: { /* NV2080_CTRL_CMD_INTERNAL_INIT_USER_SHARED_DATA
+			   *
+			   * The guest kernel driver hands the GSP-RM the physical
+			   * address of the RUSD (RM user shared data) page it
+			   * allocated; on real hardware the GSP registers the
+			   * memdesc and keeps the page's sequence-guarded fields
+			   * (clocks, BAR1, utilisation, ...) populated, and 0
+			   * de-initialises it. Nothing here performs that upkeep,
+			   * and consumers treat a zeroed sequence word as "data
+			   * invalid" and skip the fields, so the correct emulated
+			   * behaviour is to acknowledge the registration, echo the
+			   * request (the caller may read the address back) and log
+			   * the address once so the page can be correlated with
+			   * guest RAM during diagnosis. */
+		u8 *rp = reply + GSP_RM_CTRL_HDR_SIZE;
+		const u8 *pp = req_data + GSP_RM_CTRL_HDR_SIZE;
+
+		if (req.paramsSize >= 8) {
+			u64 phys_addr;
+
+			memcpy(&phys_addr, pp, 8);
+			memcpy(rp, pp, req.paramsSize);
+			rm->rusd_phys_addr = phys_addr;
+			rm->rusd_init_seen = true;
+			nv_vgpu_info(ctx->vgpu,
+				     "vgsp-rm: INIT_USER_SHARED_DATA physAddr=0x%llx (RUSD registered; fields left at sequence 0 = 'data invalid', consumers skip)",
+				     phys_addr);
+			out_status = 0;
+			out_params_size = req.paramsSize;
+		} else {
+			out_status = 0;
+			out_params_size = 0;
+		}
+		break;
+	}
+
 	case 0x2080a097: { /* client-pending engine-context query (session 75)
 			   *
 			   * libnvidia-eglcore issues this via NVOS54 and then