guest-diag/pin scanner: allow Xorg/X as pin targets (GL path)

The nvidia-push DMA test in Xorg screen init fails with 'Failed to initialize
DMA / Failed to allocate push buffer' (observed r816) because the X server's
pages are never pinned - the scanner excluded Xorg/X alongside the
nvidia-smi/persistenced transients. Xorg is long-lived and a legitimate GL
client of the vGPU, so it is now a valid pin target; the transient exclusions
stay.

1 files changed, 8 insertions, 1 deletions

diff --git a/tools/guest-diag/guest_pin_stream.py b/tools/guest-diag/guest_pin_stream.py
index 175ed23..8768f2f 100644
--- a/tools/guest-diag/guest_pin_stream.py
+++ b/tools/guest-diag/guest_pin_stream.py
@@ -1432,7 +1432,14 @@ def cdt_pid():
     # Processes that hold a /dev/nvidia* fd but are not CUDA clients; the
     # scanner must never commit to them (a transient nvidia-smi at boot was
     # picked once and its exited pagemap read back EOF forever).
-    non_clients = ("nvidia-smi", "nvidia-persistenced", "Xorg", "X")
+    #
+    # SESSION 146: Xorg/X used to be excluded here too, but the GL/GZDOOM
+    # path needs the X server's pages pinned - Xorg screen init fails with
+    # "Failed to initialize DMA / Failed to allocate push buffer" when the
+    # nvidia-push buffers cannot be resolved (observed r816). Xorg is a
+    # long-lived process (unlike the nvidia-smi transient the exclusion
+    # guarded against), so it is a valid, stable pin target.
+    non_clients = ("nvidia-smi", "nvidia-persistenced")
     cands = []
     for d in os.listdir('/proc'):
         if not d.isdigit():