pc, pc64: park application processors in rebootcode with mmu off

instead of having application processors spin in mpshutdown()
with mmu on, and be subject to reboot() overriding kernel text
and modifying page tables, park the application processors in
rebootcode idle loop with the mmu off.

1 files changed, 31 insertions, 18 deletions

diff --git a/sys/src/9/pc64/main.c b/sys/src/9/pc64/main.c
index fc1bfeb92..dd9e2d8f2 100644
--- a/sys/src/9/pc64/main.c
+++ b/sys/src/9/pc64/main.c
@@ -336,18 +336,45 @@ main()
 	schedinit();
 }
 
+static void
+rebootjump(uintptr entry, uintptr code, ulong size)
+{
+	void (*f)(uintptr, uintptr, ulong);
+
+	splhi();
+	arch->introff();
+
+	/*
+	 * This allows the reboot code to turn off the page mapping
+	 */
+	*mmuwalk(m->pml4, 0, 3, 0) = *mmuwalk(m->pml4, KZERO, 3, 0);
+	*mmuwalk(m->pml4, 0, 2, 0) = *mmuwalk(m->pml4, KZERO, 2, 0);
+	mmuflushtlb();
+
+	/* setup reboot trampoline function */
+	f = (void*)REBOOTADDR;
+	memmove(f, rebootcode, sizeof(rebootcode));
+
+	/* off we go - never to return */
+	coherence();
+	(*f)(entry, code, size);
+
+	for(;;);
+}
+
+
 void
 exit(int)
 {
 	cpushutdown();
+	if(m->machno)
+		rebootjump(0, 0, 0);
 	arch->reset();
 }
 
 void
 reboot(void *entry, void *code, ulong size)
 {
-	void (*f)(uintptr, uintptr, ulong);
-
 	writeconf();
 	vmxshutdown();
 
@@ -362,7 +389,7 @@ reboot(void *entry, void *code, ulong size)
 		sched();
 	}
 	cpushutdown();
-
+	delay(1000);
 	splhi();
 
 	/* turn off buffered serial console */
@@ -370,22 +397,8 @@ reboot(void *entry, void *code, ulong size)
 
 	/* shutdown devices */
 	chandevshutdown();
-	arch->introff();
-
-	/*
-	 * This allows the reboot code to turn off the page mapping
-	 */
-	*mmuwalk(m->pml4, 0, 3, 0) = *mmuwalk(m->pml4, KZERO, 3, 0);
-	*mmuwalk(m->pml4, 0, 2, 0) = *mmuwalk(m->pml4, KZERO, 2, 0);
-	mmuflushtlb();
-
-	/* setup reboot trampoline function */
-	f = (void*)REBOOTADDR;
-	memmove(f, rebootcode, sizeof(rebootcode));
 
-	/* off we go - never to return */
-	coherence();
-	(*f)((uintptr)entry & ~0xF0000000UL, (uintptr)PADDR(code), size);
+	rebootjump((uintptr)entry & ~0xF0000000UL, PADDR(code), size);
 }
 
 /*