---

yaml
---
r: 336151
b: refs/heads/master
c: 6662c34
h: refs/heads/master
i:
  336149: b4e8380
  336147: 195a993
  336143: 17e05d9
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: cb7cb2864e758a1b040040bc55e404c677c911cb
+refs/heads/master: 6662c34fa9c60a48aaa5879cb229cd9a84de9c22

trunk/arch/x86/kernel/head_32.S

@@ -292,8 +292,8 @@ default_entry:
  *	be using the global pages. 
  *
  *	NOTE! If we are on a 486 we may have no cr4 at all!
- *	Specifically, cr4 exists if and only if CPUID exists,
- *	which in turn exists if and only if EFLAGS.ID exists.
+ *	Specifically, cr4 exists if and only if CPUID exists
+ *	and has flags other than the FPU flag set.
  */
 	movl $X86_EFLAGS_ID,%ecx
 	pushl %ecx
@@ -308,6 +308,11 @@ default_entry:
 	testl %ecx,%eax
 	jz 6f			# No ID flag = no CPUID = no CR4
 
+	movl $1,%eax
+	cpuid
+	andl $~1,%edx		# Ignore CPUID.FPU
+	jz 6f			# No flags or only CPUID.FPU = no CR4
+
 	movl pa(mmu_cr4_features),%eax
 	movl %eax,%cr4