r576 diag: launch-decision + event-post payload witnesses (gsp_phys_gr_dec_log, gsp_rm_ev_log)

The GR launch-decision dump logs, for the first N draws whose fill saw
dropped pages / a partial argument set or whose decision point carries a
dstpend/copy-pending verdict: the decision verdicts, the launch's resolved
data pages (VA -> guest PA), the live deferred-write records and the pending
CE opdef entries - the operand evidence needed to explain a red draw of the
readback lottery (the wrong-but-similar page hypothesis).

The event-post witness logs every EVENT_POST_EVENT record actually sent with
its full payload (hClient/hEvent/notifyIndex/data) and send result, plus a
sentinel when post_all_events found valid events but posted none while none
were dedup-skipped. This is the evidence needed when a client parks waiting
for a completion wake-up that never arrives (the 2nd-client device-state
spin): it shows whether the post was generated, for whom, and whether the
status-queue write accepted it or dropped it (burst cap / ring full).

Both are inert by default (budget 0).

1 files changed, 24 insertions, 0 deletions

diff --git a/kernel/main.c b/kernel/main.c
index 3ee5c23..d0eb2b4 100644
--- a/kernel/main.c
+++ b/kernel/main.c
@@ -2788,6 +2788,30 @@ MODULE_PARM_DESC(gsp_phys_gr_hold_max_ms, "Absolute GR fill hold bound in ms, ke
  */
 module_param_named(gsp_phys_gr_fill_hold, gsp_phys_gr_fill_hold, uint, 0644);
 MODULE_PARM_DESC(gsp_phys_gr_fill_hold, "GR fill hold on unresolved operand pages (default 0: log-only, never hold)");
+
+/*
+ * r576 DIAG: per-boot witness budget for the GR launch-decision dump (see
+ * svc_gr_dec_dump in gsp_sema_service.c). Nonzero logs, for the first N
+ * launches whose fill saw dropped pages / a partial argument set or whose
+ * decision point carries a dstpend/copy-pending verdict: the decision
+ * verdicts, the launch's resolved data pages (VA -> guest PA), the live
+ * deferred-write records and the pending CE opdef entries. 0 (default) =
+ * off.
+ */
+module_param_named(gsp_phys_gr_dec_log, gsp_phys_gr_dec_log_max, uint, 0644);
+MODULE_PARM_DESC(gsp_phys_gr_dec_log, "GR launch-decision dump budget per boot (default 0: off)");
+
+/*
+ * r576 DIAG: per-boot witness budget for GSP event-post payloads (see
+ * gsp_rm_evlog_post in gsp_rm_emulation.c). Nonzero logs every
+ * EVENT_POST_EVENT record actually sent, with its full payload
+ * (hClient/hEvent/notifyIndex/data) and send result - the evidence needed
+ * when a client parks waiting for a completion wake-up that never arrives.
+ * 0 (default) = off.
+ */
+module_param_named(gsp_rm_ev_log, gsp_rm_ev_log_max, uint, 0644);
+MODULE_PARM_DESC(gsp_rm_ev_log, "GSP event-post payload witness budget per boot (default 0: off)");
+
 module_param_named(gsp_sema_walk_trace, gsp_sema_walk_trace, uint, 0644);
 MODULE_PARM_DESC(gsp_sema_walk_trace, "Trace GMMU walks for unresolved high-VA operands (default 0: off)");
 module_param_named(gsp_sema_winfill, gsp_sema_winfill, bool, 0644);