git: 9front

Download patch

ref: 38fc62546a3e480b296f4538f99d00cbd2dcb3ff
parent: f17dd78b96f5ab3be0ab991542f28ee7b61502f5
author: cinap_lenrek <cinap_lenrek@felloff.net>
date: Sat Jul 8 14:19:20 EDT 2023

devvmx: restore previous initial value for xcr0

as the processor manual states, xcr0 should be 1 on reset
(if extended states are supported).

--- a/sys/src/9/pc/devvmx.c
+++ b/sys/src/9/pc/devvmx.c
@@ -1063,7 +1063,7 @@
 #endif
 	fpinit();
 	fpsave(&vmx->fp);
-	vmx->xcr0 = m->xcr0;
+	vmx->xcr0 = m->xcr0 & 1;	/* x87 only */
 	splx(s);
 
 	memset(vmx->msrbits, -1, 4096);
--