The current code simply calls "start_kernel" directly if we're under a
hypervisor and no paravirt_ops backend wants us, because paravirt.c
registers that as a backend and it's linked last.

This was always a vain hope; start_kernel won't get far without setup.
It's also impossible for paravirt_ops backends which don't sit in the
arch/i386/kernel directory: they can't link before paravirt.o anyway.

This implements a real fallthrough if we pass all the registered
paravirt probes.

Signed-off-by: Rusty Russell <[EMAIL PROTECTED]>

===================================================================
--- a/arch/i386/kernel/Makefile
+++ b/arch/i386/kernel/Makefile
@@ -39,8 +39,6 @@ obj-$(CONFIG_EARLY_PRINTK)    += early_prin
 obj-$(CONFIG_EARLY_PRINTK)     += early_printk.o
 obj-$(CONFIG_HPET_TIMER)       += hpet.o
 obj-$(CONFIG_K8_NB)            += k8.o
-
-# Make sure this is linked after any other paravirt_ops structs: see head.S
 obj-$(CONFIG_PARAVIRT)         += paravirt.o
 
 EXTRA_AFLAGS   := -traditional
===================================================================
--- a/arch/i386/kernel/head.S
+++ b/arch/i386/kernel/head.S
@@ -502,10 +502,11 @@ startup_paravirt:
        pushl   %ecx
        pushl   %eax
 
-       /* paravirt.o is last in link, and that probe fn never returns */
        pushl   $__start_paravirtprobe
 1:
        movl    0(%esp), %eax
+       cmpl    $__stop_paravirtprobe, %eax
+       je      unhandled_paravirt
        pushl   (%eax)
        movl    8(%esp), %eax
        call    *(%esp)
@@ -517,6 +518,12 @@ 1:
 
        addl    $4, (%esp)
        jmp     1b
+
+unhandled_paravirt:
+       /* Nothing wanted us: try to die with dignity (impossible trap). */ 
+       movl    $0x1F, %edx
+       pushl   $0
+       jmp     early_fault
 #endif
 
 /*
===================================================================
--- a/arch/i386/kernel/paravirt.c
+++ b/arch/i386/kernel/paravirt.c
@@ -481,9 +481,6 @@ static int __init print_banner(void)
        return 0;
 }
 core_initcall(print_banner);
-
-/* We simply declare start_kernel to be the paravirt probe of last resort. */
-paravirt_probe(start_kernel);
 
 struct paravirt_ops paravirt_ops = {
        .name = "bare hardware",


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