vmx: update openbsd kernel heuristics

in OpenBSD 6.9 and up, the kernel (bsd, bsd.mp) still has
the ostype symbols, but bsd.rd appears to have lost them,
even when decompressed.

so, as a result, we should use what we have, which isn't
much.

1 files changed, 6 insertions, 1 deletions

diff --git a/sys/src/cmd/vmx/ksetup.c b/sys/src/cmd/vmx/ksetup.c
index 4af05ef80..34f9d96a8 100644
--- a/sys/src/cmd/vmx/ksetup.c
+++ b/sys/src/cmd/vmx/ksetup.c
@@ -728,7 +728,7 @@ obsdload(void)
 static int
 tryelf(void)
 {
-	char *s;
+	char *s, *t;
 
 	if(!elfheaders()) return 0;
 	elfdata();
@@ -736,6 +736,11 @@ tryelf(void)
 	s = symaddr(elfsym("ostype"));
 	if(s != nil && strcmp(s, "OpenBSD") == 0)
 		return obsdload();
+	/* from 6.9 up, bsd.rd has just these syms */
+	s = symaddr(elfsym("rd_root_image"));
+	t = symaddr(elfsym("rd_root_size"));
+	if(s != nil && t != nil)
+		return obsdload();
 	return 0;
 }