docs + nvkmstrace: the GL/Vulkan wall fully bisected (SESSION 65) - ALLOC_DEVICE reply status 5 (CORE_CHANNEL_ALLOC_FAILED) decoded by the LD_PRELOAD nvKms logger with a widened reply scan; the empty display capability notifier is the first missing piece (a live-gdb fill of SYS_CAP/SYS_CAPB flips the driver to the window path, proving numWindows>0 unblocks it); the residual wall is the vGPU-guest display-class rejection: nvRmApiAlloc(0xc57e) returns NV_ERR_NOT_SUPPORTED inside the guest kernel and never reaches the emulated GSP - the guest runs in vGPU mode where display/modeset classes are host-service-provided by design

1 files changed, 15 insertions, 0 deletions

diff --git a/tools/guest-diag/nvkmstrace.c b/tools/guest-diag/nvkmstrace.c
index 411de6b..ca72e46 100644
--- a/tools/guest-diag/nvkmstrace.c
+++ b/tools/guest-diag/nvkmstrace.c
@@ -3,6 +3,7 @@
 #include <stdio.h>
 #include <stdarg.h>
 #include <stdint.h>
+#include <string.h>
 #include <dlfcn.h>
 #include <sys/ioctl.h>
 
@@ -36,10 +37,24 @@ int ioctl(int fd, unsigned long req, ...)
 		if (p->address && p->size) {
 			unsigned char *q = (unsigned char *)(uintptr_t)p->address;
 			unsigned n = p->size < 64 ? p->size : 64, i;
+
 			fprintf(stderr, "  data:");
 			for (i = 0; i < n; i++)
 				fprintf(stderr, " %02x", q[i]);
 			fprintf(stderr, "\n");
+			if (p->size >= 700) {
+				/* reply.status candidates: request = 32 + 4 +
+				 * 4*1 (NvBool=NvU8) + 16*(32+4) = 616 bytes */
+				unsigned o;
+
+				for (o = 600; o <= 700; o += 4) {
+					unsigned v;
+					memcpy(&v, q + o, 4);
+					if (v <= 16)
+						fprintf(stderr, "  small@%u=%u\n",
+							o, v);
+				}
+			}
 		}
 		return rc;
 	}