Palacios Public Git Repository

To checkout Palacios execute

  git clone http://v3vee.org/palacios/palacios.web/palacios.git
This will give you the master branch. You probably want the devel branch or one of the release branches. To switch to the devel branch, simply execute
  cd palacios
  git checkout --track -b devel origin/devel
The other branches are similar.


Added correct physical delivery check for apic
[palacios.git] / palacios / src / devices / apic.c
index d439e25..427ec79 100644 (file)
@@ -11,7 +11,8 @@
  * Copyright (c) 2008, The V3VEE Project <http://www.v3vee.org> 
  * All rights reserved.
  *
- * Author: Jack Lange <jarusl@cs.northwestern.edu>
+ * Authors: Jack Lange <jarusl@cs.northwestern.edu>
+ *          Peter Dinda <pdinda@northwestern.edu> (SMP)
  *
  * This is free software.  You are permitted to use,
  * redistribute, and modify it as specified in the file "V3VEE_LICENSE".
 #include <palacios/vmm_types.h>
 
 
+
+
 #ifndef CONFIG_DEBUG_APIC
 #undef PrintDebug
 #define PrintDebug(fmt, args...)
 #endif
 
 
+#ifdef CONFIG_DEBUG_APIC
+static char * shorthand_str[] = { 
+    "(no shorthand)",
+    "(self)",
+    "(all)",
+    "(all-but-me)",
+};
+
+static char * deliverymode_str[] = { 
+    "(fixed)",
+    "(lowest priority)",
+    "(SMI)",
+    "(reserved)",
+    "(NMI)",
+    "(INIT)",
+    "(Start Up)",
+    "(ExtInt)",
+};
+#endif
+
+// Temporary removal of locking
+#define v3_lock(p) p=p
+#define v3_unlock(p) p=p
+
+
 typedef enum { APIC_TMR_INT, APIC_THERM_INT, APIC_PERF_INT, 
               APIC_LINT0_INT, APIC_LINT1_INT, APIC_ERR_INT } apic_irq_type_t;
 
 #define APIC_FIXED_DELIVERY  0x0
+#define APIC_LOWEST_DELIVERY 0x1
 #define APIC_SMI_DELIVERY    0x2
+#define APIC_RES1_DELIVERY   0x3
 #define APIC_NMI_DELIVERY    0x4
 #define APIC_INIT_DELIVERY   0x5
+#define APIC_SIPI_DELIVERY   0x6
 #define APIC_EXTINT_DELIVERY 0x7
 
+#define APIC_SHORTHAND_NONE        0x0
+#define APIC_SHORTHAND_SELF        0x1
+#define APIC_SHORTHAND_ALL         0x2
+#define APIC_SHORTHAND_ALL_BUT_ME  0x3
+
+#define APIC_DEST_PHYSICAL    0x0
+#define APIC_DEST_LOGICAL     0x1
+
 
 #define BASE_ADDR_MSR     0x0000001B
 #define DEFAULT_BASE_ADDR 0xfee00000
@@ -116,10 +155,6 @@ typedef enum { APIC_TMR_INT, APIC_THERM_INT, APIC_PERF_INT,
 #define EXT_INT_LOC_VEC_TBL_OFFSET2       0x520   // 0x500 - 0x530
 #define EXT_INT_LOC_VEC_TBL_OFFSET3       0x530   // 0x500 - 0x530
 
-
-
-
-
 struct apic_msr {
     union {
        uint64_t value;
@@ -128,15 +163,17 @@ struct apic_msr {
            uint8_t bootstrap_cpu : 1;
            uint8_t rsvd2         : 2;
            uint8_t apic_enable   : 1;
-           uint64_t base_addr   : 40;
-           uint32_t rsvd3         : 12;
+           uint64_t base_addr    : 40;
+           uint32_t rsvd3        : 12;
        } __attribute__((packed));
     } __attribute__((packed));
 } __attribute__((packed));
 
 
 
-typedef enum {INIT, SIPI, STARTED} ipi_state_t; 
+typedef enum {INIT_ST, 
+             SIPI, 
+             STARTED} ipi_state_t; 
 
 struct apic_dev_state;
 
@@ -190,9 +227,16 @@ struct apic_state {
 
     struct guest_info * core;
 
+    void * controller_handle;
+
+    struct v3_timer * timer;
+
     uint32_t eoi;
 
     v3_lock_t  lock;
+
+    // debug
+    uint8_t in_icr;   
 };
 
 
@@ -200,15 +244,19 @@ struct apic_state {
 
 struct apic_dev_state {
     int num_apics;
+    //    v3_lock_t ipi_lock;   // acquired by route_ipi - only one IPI active at a time
 
     struct apic_state apics[0];
 } __attribute__((packed));
 
 
 
+
+
 static int apic_read(struct guest_info * core, addr_t guest_addr, void * dst, uint_t length, void * priv_data);
 static int apic_write(struct guest_info * core, addr_t guest_addr, void * src, uint_t length, void * priv_data);
 
+// No lcoking done
 static void init_apic_state(struct apic_state * apic, uint32_t id) {
     apic->base_addr = DEFAULT_BASE_ADDR;
 
@@ -240,7 +288,7 @@ static void init_apic_state(struct apic_state * apic, uint32_t id) {
 
     apic->lapic_id.val = id;
     
-    apic->ipi_state = INIT;
+    apic->ipi_state = INIT_ST;
 
     // The P6 has 6 LVT entries, so we set the value to (6-1)...
     apic->apic_ver.val = 0x80050010;
@@ -266,11 +314,15 @@ static void init_apic_state(struct apic_state * apic, uint32_t id) {
     apic->spec_eoi.val = 0x00000000;
 
     v3_lock_init(&(apic->lock));
+
+    //debug
+    apic->in_icr=0;
 }
 
 
 
 
+// MSR handler - locks apic itself
 static int read_apic_msr(struct guest_info * core, uint_t msr, v3_msr_t * dst, void * priv_data) {
     struct apic_dev_state * apic_dev = (struct apic_dev_state *)priv_data;
     struct apic_state * apic = &(apic_dev->apics[core->cpu_id]);
@@ -282,7 +334,7 @@ static int read_apic_msr(struct guest_info * core, uint_t msr, v3_msr_t * dst, v
     return 0;
 }
 
-
+// MSR handler - locks apic itself
 static int write_apic_msr(struct guest_info * core, uint_t msr, v3_msr_t src, void * priv_data) {
     struct apic_dev_state * apic_dev = (struct apic_dev_state *)priv_data;
     struct apic_state * apic = &(apic_dev->apics[core->cpu_id]);
@@ -304,7 +356,9 @@ static int write_apic_msr(struct guest_info * core, uint_t msr, v3_msr_t src, vo
 
     apic->base_addr = src.value;
 
-    if (v3_hook_full_mem(core->vm_info, core->cpu_id, apic->base_addr, apic->base_addr + PAGE_SIZE_4KB, apic_read, apic_write, apic_dev) == -1) {
+    if (v3_hook_full_mem(core->vm_info, core->cpu_id, apic->base_addr, 
+                        apic->base_addr + PAGE_SIZE_4KB, 
+                        apic_read, apic_write, apic_dev) == -1) {
        PrintError("apic %u: core %u: Could not hook new APIC Base address\n",
                   apic->lapic_id.val, core->cpu_id);
        v3_unlock(apic->lock);
@@ -317,7 +371,12 @@ static int write_apic_msr(struct guest_info * core, uint_t msr, v3_msr_t src, vo
 
 
 // irq_num is the bit offset into a 256 bit buffer...
-static int activate_apic_irq(struct apic_state * apic, uint32_t irq_num) {
+// return values
+//    -1 = error
+//     0 = OK, no interrupt needed now
+//     1 = OK, interrupt needed now
+// the caller is expeced to have locked the apic
+static int activate_apic_irq_nolock(struct apic_state * apic, uint32_t irq_num) {
     int major_offset = (irq_num & ~0x00000007) >> 3;
     int minor_offset = irq_num & 0x00000007;
     uint8_t * req_location = apic->int_req_reg + major_offset;
@@ -325,32 +384,39 @@ static int activate_apic_irq(struct apic_state * apic, uint32_t irq_num) {
     uint8_t flag = 0x1 << minor_offset;
 
 
-
-    if (irq_num <= 15) {
-//     PrintError("apic %u: core ?: Attempting to raise an invalid interrupt: %d\n", apic->lapic_id.val,irq_num);
+    if (irq_num <= 15 || irq_num>255) {
+       PrintError("apic %u: core %d: Attempting to raise an invalid interrupt: %d\n", 
+                  apic->lapic_id.val, apic->core->cpu_id, irq_num);
        return -1;
     }
 
 
-    PrintDebug("apic %u: core ?: Raising APIC IRQ %d\n", apic->lapic_id.val, irq_num);
+    PrintDebug("apic %u: core %d: Raising APIC IRQ %d\n", apic->lapic_id.val, apic->core->cpu_id, irq_num);
 
     if (*req_location & flag) {
-       //V3_Print("Interrupts coallescing\n");
+       PrintDebug("Interrupt %d  coallescing\n", irq_num);
+       return 0;
     }
 
     if (*en_location & flag) {
        *req_location |= flag;
+
+       if (apic->in_icr) { 
+           PrintError("apic %u: core %d: activate_apic_irq_nolock to deliver irq 0x%x when in_icr=1\n",  apic->lapic_id.val, apic->core->cpu_id, irq_num);
+           //      return 0;
+       }
+
+       return 1;
     } else {
-       PrintDebug("apic %u: core ?: Interrupt  not enabled... %.2x\n", 
-                  apic->lapic_id.val, *en_location);
+       PrintDebug("apic %u: core %d: Interrupt  not enabled... %.2x\n", 
+                  apic->lapic_id.val, apic->core->cpu_id,*en_location);
        return 0;
     }
 
-    return 0;
 }
 
 
-
+// Caller is expected to have locked the apic
 static int get_highest_isr(struct apic_state * apic) {
     int i = 0, j = 0;
 
@@ -372,7 +438,7 @@ static int get_highest_isr(struct apic_state * apic) {
 }
  
 
-
+// Caller is expected to have locked the apic
 static int get_highest_irr(struct apic_state * apic) {
     int i = 0, j = 0;
 
@@ -395,7 +461,7 @@ static int get_highest_irr(struct apic_state * apic) {
  
 
 
-
+// Caller is expected to have locked the apic
 static int apic_do_eoi(struct apic_state * apic) {
     int isr_irq = get_highest_isr(apic);
 
@@ -427,8 +493,8 @@ static int apic_do_eoi(struct apic_state * apic) {
     return 0;
 }
  
-
-static int activate_internal_irq(struct apic_state * apic, apic_irq_type_t int_type) {
+// Caller is expected to have locked the apic
+static int activate_internal_irq_nolock(struct apic_state * apic, apic_irq_type_t int_type) {
     uint32_t vec_num = 0;
     uint32_t del_mode = 0;
     int masked = 0;
@@ -478,7 +544,7 @@ static int activate_internal_irq(struct apic_state * apic, apic_irq_type_t int_t
 
     if (del_mode == APIC_FIXED_DELIVERY) {
        //PrintDebug("Activating internal APIC IRQ %d\n", vec_num);
-       return activate_apic_irq(apic, vec_num);
+       return activate_apic_irq_nolock(apic, vec_num);
     } else {
        PrintError("apic %u: core ?: Unhandled Delivery Mode\n", apic->lapic_id.val);
        return -1;
@@ -486,12 +552,12 @@ static int activate_internal_irq(struct apic_state * apic, apic_irq_type_t int_t
 }
 
 
-
+// Caller is expected to have locked the destination apic
 static inline int should_deliver_cluster_ipi(struct guest_info * dst_core, 
                                             struct apic_state * dst_apic, uint8_t mda) {
 
-    if         ( ((mda & 0xf0) == (dst_apic->log_dst.dst_log_id & 0xf0)) &&     // (I am in the cluster and
-         ((mda & 0x0f) & (dst_apic->log_dst.dst_log_id & 0x0f)) ) {  //  I am in the set)
+    if         ( ((mda & 0xf0) == (dst_apic->log_dst.dst_log_id & 0xf0)) &&  /* (I am in the cluster and */
+         ((mda & 0x0f) & (dst_apic->log_dst.dst_log_id & 0x0f)) ) {  /*  I am in the set)        */
 
        PrintDebug("apic %u core %u: accepting clustered IRQ (mda 0x%x == log_dst 0x%x)\n",
                   dst_apic->lapic_id.val, dst_core->cpu_id, mda, 
@@ -500,12 +566,13 @@ static inline int should_deliver_cluster_ipi(struct guest_info * dst_core,
        return 1;
     } else {
        PrintDebug("apic %u core %u: rejecting clustered IRQ (mda 0x%x != log_dst 0x%x)\n",
-                  dst_apic->lapic_id.val, dst_core->cpu_id, mda, dst_
+                  dst_apic->lapic_id.val, dst_core->cpu_id, mda, 
                   dst_apic->log_dst.dst_log_id);
        return 0;
     }
 }
 
+// Caller is expected to have locked the destiation apic
 static inline int should_deliver_flat_ipi(struct guest_info * dst_core,
                                          struct apic_state * dst_apic, uint8_t mda) {
 
@@ -514,29 +581,42 @@ static inline int should_deliver_flat_ipi(struct guest_info * dst_core,
        PrintDebug("apic %u core %u: accepting flat IRQ (mda 0x%x == log_dst 0x%x)\n",
                   dst_apic->lapic_id.val, dst_core->cpu_id, mda, 
                   dst_apic->log_dst.dst_log_id);
-      return 1;
+
+       return 1;
+
   } else {
+
        PrintDebug("apic %u core %u: rejecting flat IRQ (mda 0x%x != log_dst 0x%x)\n",
                   dst_apic->lapic_id.val, dst_core->cpu_id, mda, 
                   dst_apic->log_dst.dst_log_id);
-      return 0;
+       return 0;
   }
 }
 
 
-
+// Caller is expected to have locked the destiation apic
 static int should_deliver_ipi(struct guest_info * dst_core, 
                              struct apic_state * dst_apic, uint8_t mda) {
 
-    if (mda == 0xff) {
-       // always deliver broadcast
-       return 1;
-    }
 
     if (dst_apic->dst_fmt.model == 0xf) {
-       return should_deliver_cluster_ipi(dst_core, dst_apic, mda);
-    } else if (dst_apic->dst_fmt.model == 0x0) {
+
+       if (mda == 0xff) {
+           /* always deliver broadcast */
+           return 1;
+       }
+
        return should_deliver_flat_ipi(dst_core, dst_apic, mda);
+
+    } else if (dst_apic->dst_fmt.model == 0x0) {
+
+       if (mda == 0xff) {
+           /*  always deliver broadcast */
+           return 1;
+       }
+
+       return should_deliver_cluster_ipi(dst_core, dst_apic, mda);
+
     } else {
        PrintError("apic %u core %u: invalid destination format register value 0x%x for logical mode delivery.\n", 
                   dst_apic->lapic_id.val, dst_core->cpu_id, dst_apic->dst_fmt.model);
@@ -544,44 +624,59 @@ static int should_deliver_ipi(struct guest_info * dst_core,
     }
 }
 
-
-static int deliver_ipi(struct guest_info * core, 
-                      struct apic_state * src_apic, 
+// Caller is expected to have locked the destination apic
+// Only the src_apic pointer is used
+static int deliver_ipi(struct apic_state * src_apic, 
                       struct apic_state * dst_apic, 
                       uint32_t vector, uint8_t del_mode) {
 
+
     struct guest_info * dst_core = dst_apic->core;
+    int do_xcall;
 
     switch (del_mode) {
 
-       case 0:  //fixed
-       case 1: // lowest priority
-           PrintDebug("icc_bus: delivering IRQ to core %u\n", dst_core->cpu_id); 
+       case APIC_FIXED_DELIVERY:  
+       case APIC_LOWEST_DELIVERY:
+           // lowest priority - 
+           // caller needs to have decided which apic to deliver to!
+
+           PrintDebug("delivering IRQ %d to core %u\n", vector, dst_core->cpu_id); 
 
-           activate_apic_irq(dst_apic, vector);
+           do_xcall=activate_apic_irq_nolock(dst_apic, vector);
+           
+           if (do_xcall<0) { 
+               PrintError("Failed to activate apic irq!\n");
+               return -1;
+           }
 
-           if (dst_apic != src_apic) { 
+           if (do_xcall && (dst_apic != src_apic)) { 
                // Assume core # is same as logical processor for now
                // TODO FIX THIS FIX THIS
                // THERE SHOULD BE:  guestapicid->virtualapicid map,
                //                   cpu_id->logical processor map
                //     host maitains logical proc->phsysical proc
-               PrintDebug("icc_bus: non-local core, forcing it to exit\n"); 
+               PrintDebug(" non-local core with new interrupt, forcing it to exit now\n"); 
 
-               v3_interrupt_cpu(core->vm_info, dst_core->cpu_id, 0);
+#ifdef CONFIG_MULTITHREAD_OS
+               v3_interrupt_cpu(dst_core->vm_info, dst_core->cpu_id, 0);
+#else
+               V3_ASSERT(0);
+#endif
            }
 
            break;
-       case 5: { //INIT
 
-           PrintDebug("icc_bus: INIT delivery to core %u\n", dst_core->cpu_id);
+       case APIC_INIT_DELIVERY: { 
+
+           PrintDebug(" INIT delivery to core %u\n", dst_core->cpu_id);
 
            // TODO: any APIC reset on dest core (shouldn't be needed, but not sure...)
 
            // Sanity check
-           if (dst_apic->ipi_state != INIT) { 
-               PrintError("icc_bus: Warning: core %u is not in INIT state (mode = %d), ignored\n",
-                          dst_core->cpu_id, dst_core->cpu_mode);
+           if (dst_apic->ipi_state != INIT_ST) { 
+               PrintError(" Warning: core %u is not in INIT state (mode = %d), ignored (assuming this is the deassert)\n",
+                          dst_core->cpu_id, dst_apic->ipi_state);
                // Only a warning, since INIT INIT SIPI is common
                break;
            }
@@ -595,16 +690,16 @@ static int deliver_ipi(struct guest_info * core,
            // in both cases, it will quickly notice this transition 
            // in particular, we should not need to force an exit here
 
-           PrintDebug("icc_bus: INIT delivery done\n");
+           PrintDebug(" INIT delivery done\n");
 
            break;                                                      
        }
-       case 6: { //SIPI
+       case APIC_SIPI_DELIVERY: { 
 
            // Sanity check
            if (dst_apic->ipi_state != SIPI) { 
-               PrintError("icc_bus: core %u is not in SIPI state (mode = %d), ignored!\n",
-                          dst_core->cpu_id, dst_core->cpu_mode);
+               PrintError(" core %u is not in SIPI state (mode = %d), ignored!\n",
+                          dst_core->cpu_id, dst_apic->ipi_state);
                break;
            }
 
@@ -623,151 +718,301 @@ static int deliver_ipi(struct guest_info * core,
            dst_core->segments.cs.limit = 0xffff;
            dst_core->segments.cs.base = vector << 12;
 
-           PrintDebug("icc_bus: SIPI delivery (0x%x -> 0x%x:0x0) to core %u\n",
-                      vec, dst_core->segments.cs.selector, dst_core->cpu_id);
+           PrintDebug(" SIPI delivery (0x%x -> 0x%x:0x0) to core %u\n",
+                      vector, dst_core->segments.cs.selector, dst_core->cpu_id);
            // Maybe need to adjust the APIC?
            
            // We transition the target core to SIPI state
            dst_core->core_run_state = CORE_RUNNING;  // note: locking should not be needed here
-
+           dst_apic->ipi_state = STARTED;
+           
            // As with INIT, we should not need to do anything else
-
-           PrintDebug("icc_bus: SIPI delivery done\n");
-
+           
+           PrintDebug(" SIPI delivery done\n");
+           
            break;                                                      
        }
-       case 2: // SMI                  
-       case 3: // reserved                                             
-       case 4: // NMI                                  
-       case 7: // ExtInt
+       case APIC_SMI_DELIVERY: 
+       case APIC_RES1_DELIVERY: // reserved                                            
+       case APIC_NMI_DELIVERY:
+       case APIC_EXTINT_DELIVERY: // ExtInt
        default:
            PrintError("IPI %d delivery is unsupported\n", del_mode); 
            return -1;
     }
-
+    
     return 0;
-
+    
 }
 
+static struct apic_state * find_physical_apic(struct apic_dev_state *apic_dev, struct int_cmd_reg *icr)
+{
+    int i;
+    
+    if (icr->dst >0 && icr->dst < apic_dev->num_apics) { 
+       // see if it simply is the core id
+       if (apic_dev->apics[icr->dst].lapic_id.val == icr->dst) { 
+           return &(apic_dev->apics[icr->dst]);
+       }
+    }
 
-static int route_ipi(struct guest_info * core, struct apic_dev_state * apic_dev,
-                    struct apic_state * src_apic,  uint32_t icr_val) {
-    struct int_cmd_reg * icr = (struct int_cmd_reg *)&icr_val;
-    struct apic_state * dest_apic = NULL;
-
-    PrintDebug("icc_bus: icc_bus=%p, src_apic=%u, icr_data=%llx, extirq=%u\n", 
-              icc_bus, src_apic, icr_data, extirq);
-
-
-    // initial sanity checks
-    if (src_apic == NULL) { 
-       PrintError("icc_bus: Apparently sending from unregistered apic id=%d\n", 
-                  src_apic->core->cpu_id);
-       return -1;
+    for (i=0;i<apic_dev->num_apics;i++) { 
+       if (apic_dev->apics[i].lapic_id.val == icr->dst) { 
+           return &(apic_dev->apics[i]);
+       }
     }
+    
+    return NULL;
 
+}
+
+// route_ipi is responsible for all locking
+// the assumption is that you enter with no locks
+// there is a global lock for the icc bus, so only
+// one route_ipi progresses at any time
+// destination apics are locked as needed
+// if multiple apic locks are acquired at any point,
+// this is done in the order of the array, so no
+// deadlock should be possible
+static int route_ipi(struct apic_dev_state * apic_dev,
+                    struct apic_state * src_apic, 
+                    struct int_cmd_reg * icr) {
+    struct apic_state * dest_apic = NULL;
 
-    if ((icr->dst_mode == 0) && (icr->dst >= apic_dev->num_apics)) { 
-       PrintError("icc_bus: Attempted send to unregistered apic id=%u\n", 
-                  icr->dst);
-       return -1;
-    }
 
-    dest_apic =  &(apic_dev->apics[icr->dst]);
+    //v3_lock(apic_dev->ipi_lock);  // this may not be needed
+    // now I know only one IPI is being routed, this one
+    // also, I do not have any apic locks
+    // I need to acquire locks on pairs of src/dest apics
+    // and I will do that using the total order
+    // given by their cores
 
 
-    PrintDebug("icc_bus: IPI %s %u from %s %u to %s %s %u (icr=0x%llx, extirq=%u)\n",
+    PrintDebug("apic: IPI %s %u from apic %p to %s %s %u (icr=0x%llx)\n",
               deliverymode_str[icr->del_mode], 
               icr->vec, 
-              (src_apic == state->ioapic_id) ? "ioapic" : "apic",
               src_apic,               
               (icr->dst_mode == 0) ? "(physical)" : "(logical)", 
               shorthand_str[icr->dst_shorthand], 
               icr->dst,
-              icr->val,
-              extirq);
+              icr->val);
+
+#if 0
+        if (icr->vec!=48) { 
+           V3_Print("apic: IPI %s %u from apic %p to %s %s %u (icr=0x%llx)\n",
+                   deliverymode_str[icr->del_mode], 
+                   icr->vec, 
+                   src_apic,          
+                   (icr->dst_mode == 0) ? "(physical)" : "(logical)", 
+                   shorthand_str[icr->dst_shorthand], 
+                   icr->dst,
+                   icr->val);
+       }
+
+#endif
 
 
     switch (icr->dst_shorthand) {
 
-       case 0:  // no shorthand
-           if (icr->dst_mode == 0) { 
-               // physical delivery
+       case APIC_SHORTHAND_NONE:  // no shorthand
+           if (icr->dst_mode == APIC_DEST_PHYSICAL) { 
+
+               dest_apic=find_physical_apic(apic_dev,icr);
+               
+               if (dest_apic==NULL) { 
+                   PrintError("apic: Attempted send to unregistered apic id=%u\n", icr->dst);
+                   goto route_ipi_out_bad;
+               }
+
+
+       
+               //V3_Print("apic: phsyical destination of %u (apic %u at 0x%p)\n", icr->dst,dest_apic->lapic_id.val,dest_apic);
+
+               v3_lock(dest_apic->lock);
 
-               if (deliver_ipi(core, src_apic, dest_apic, 
+               if (deliver_ipi(src_apic, dest_apic, 
                                icr->vec, icr->del_mode) == -1) {
-                   PrintError("Error: Could not deliver IPI\n");
-                   return -1;
+                   PrintError("apic: Could not deliver IPI\n");
+                   v3_unlock(dest_apic->lock);
+                   goto route_ipi_out_bad;
                }
 
-           } else {
-               // logical delivery
-               int i;
-               uint8_t mda = icr->dst;
-
-               for (i = 0; i < apic_dev->num_apics; i++) { 
-                    dest_apic = &(apic_dev->apics[i]);
-                    int del_flag = should_deliver_ipi(dest_apic->core, dest_apic, mda);
-                    
-                    if (del_flag == -1) {
-                        PrintError("Error checking delivery mode\n");
-                        return -1;
-                    } else if (del_flag == 1) {
-                       if (deliver_ipi(core, src_apic, dest_apic, 
+               v3_unlock(dest_apic->lock);
+
+               //V3_Print("apic: done\n");
+
+           } else if (icr->dst_mode == APIC_DEST_LOGICAL) {
+               
+               if (icr->del_mode!=APIC_LOWEST_DELIVERY ) { 
+                   // logical, but not lowest priority
+                   // we immediately trigger
+                   // fixed, smi, reserved, nmi, init, sipi, etc
+                   int i;
+                   
+                   uint8_t mda = icr->dst;
+                   
+                   for (i = 0; i < apic_dev->num_apics; i++) { 
+                       
+                       dest_apic = &(apic_dev->apics[i]);
+                       
+                       v3_lock(dest_apic->lock);
+                       
+                       int del_flag = should_deliver_ipi(dest_apic->core, dest_apic, mda);
+                       
+                       if (del_flag == -1) {
+                           PrintError("apic: Error checking delivery mode\n");
+                           v3_unlock(dest_apic->lock);
+                           goto route_ipi_out_bad;
+                       } else if (del_flag == 1) {
+                           if (deliver_ipi(src_apic, dest_apic, 
+                                           icr->vec, icr->del_mode) == -1) {
+                               PrintError("apic: Error: Could not deliver IPI\n");
+                               v3_unlock(dest_apic->lock);
+                               goto route_ipi_out_bad;
+                           }
+                       }
+                       
+                       v3_unlock(dest_apic->lock);
+                   }
+               } else {  //APIC_LOWEST_DELIVERY
+                   // logical, lowest priority
+                   // scan, keeping a lock on the current best, then trigger
+                   int i;
+                   int have_cur_lock;
+                   struct apic_state * cur_best_apic = NULL;
+                   
+                   uint8_t mda = icr->dst;
+                   
+                   have_cur_lock=0;
+
+
+                   // Note that even if there are multiple concurrent 
+                   // copies of this loop executing, they are all 
+                   // locking in the same order
+
+                   for (i = 0; i < apic_dev->num_apics; i++) { 
+                       
+                       dest_apic = &(apic_dev->apics[i]);
+                       
+                       v3_lock(dest_apic->lock);
+                       have_cur_lock=1;
+                       
+                       int del_flag = should_deliver_ipi(dest_apic->core, dest_apic, mda);
+                       
+                       if (del_flag == -1) {
+                           PrintError("apic: Error checking delivery mode\n");
+                           v3_unlock(dest_apic->lock);
+                           if (cur_best_apic && cur_best_apic!=dest_apic) { 
+                               v3_unlock(cur_best_apic->lock);
+                           }
+                           goto route_ipi_out_bad;
+                       } else if (del_flag == 1) {
+                           // update priority for lowest priority scan
+                           if (!cur_best_apic) {
+                               cur_best_apic=dest_apic;  // note we leave it locked
+                               have_cur_lock=0;          // we will unlock as cur_best_apic
+                           } else if (dest_apic->task_prio.val < cur_best_apic->task_prio.val) {
+                               // we now unlock the current best one and then switch
+                               // so in the end we have a lock on the new cur_best_apic
+                               v3_unlock(cur_best_apic->lock);
+                               cur_best_apic=dest_apic;
+                               have_cur_lock=0; // will unlock as cur_best_apic
+                           } 
+                       }
+                       if (have_cur_lock) {
+                           v3_unlock(dest_apic->lock);
+                       }
+                       
+                   }
+                   // now we will deliver to the best one if it exists
+                   // and it is locked
+                   if (!cur_best_apic) { 
+                       PrintDebug("apic: lowest priority deliver, but no destinations!\n");
+                   } else {
+                       if (deliver_ipi(src_apic, cur_best_apic, 
                                        icr->vec, icr->del_mode) == -1) {
-                           PrintError("Error: Could not deliver IPI\n");
-                           return -1;
+                           PrintError("apic: Error: Could not deliver IPI\n");
+                           v3_unlock(cur_best_apic->lock);
+                           goto route_ipi_out_bad;
+                       } else {
+                           v3_unlock(cur_best_apic->lock);
                        }
+                           //V3_Print("apic: logical, lowest priority delivery to apic %u\n",cur_best_apic->lapic_id.val);
                    }
                }
            }
-           
+
            break;
            
-       case 1:  // self
+       case APIC_SHORTHAND_SELF:  // self
 
-           if (icr->dst_mode == 0) { 
-               if (deliver_ipi(core, src_apic, src_apic, icr->vec, icr->del_mode) == -1) {
-                   PrintError("Could not deliver IPI\n");
-                   return -1;
+           /* I assume I am already locked! */
+
+           if (src_apic == NULL) {    /* this is not an apic, but it's trying to send to itself??? */
+               PrintError("apic: Sending IPI to self from generic IPI sender\n");
+               break;
+           }
+
+           v3_lock(src_apic->lock);
+
+           if (icr->dst_mode == APIC_DEST_PHYSICAL)  {  /* physical delivery */
+               if (deliver_ipi(src_apic, src_apic, icr->vec, icr->del_mode) == -1) {
+                   PrintError("apic: Could not deliver IPI to self (physical)\n");
+                   v3_unlock(src_apic->lock);
+                   goto route_ipi_out_bad;
+               }
+           } else if (icr->dst_mode == APIC_DEST_LOGICAL) {  /* logical delivery */
+               PrintError("apic: use of logical delivery in self (untested)\n");
+               if (deliver_ipi(src_apic, src_apic, icr->vec, icr->del_mode) == -1) {
+                   PrintError("apic: Could not deliver IPI to self (logical)\n");
+                   v3_unlock(src_apic->lock);
+                   goto route_ipi_out_bad;
                }
-           } else {
-               // logical delivery
-               PrintError("icc_bus: use of logical delivery in self is not yet supported.\n");
-               return -1;
            }
+           v3_unlock(src_apic->lock);
            break;
            
-       case 2: 
-       case 3: { // all and all-but-me
-           // assuming that logical verus physical doesn't matter
-           // although it is odd that both are used
+       case APIC_SHORTHAND_ALL: 
+       case APIC_SHORTHAND_ALL_BUT_ME: { /* all and all-but-me */
+           /* assuming that logical verus physical doesn't matter
+              although it is odd that both are used */
+
            int i;
 
            for (i = 0; i < apic_dev->num_apics; i++) { 
                dest_apic = &(apic_dev->apics[i]);
-
-               if ((dest_apic != src_apic) || (icr->dst_shorthand == 2)) { 
-                   if (deliver_ipi(core, src_apic, dest_apic, icr->vec, icr->del_mode) == -1) {
-                       PrintError("Error: Could not deliver IPI\n");
-                       return -1;
+               
+               
+               if ((dest_apic != src_apic) || (icr->dst_shorthand == APIC_SHORTHAND_ALL)) { 
+                   v3_lock(dest_apic->lock);
+                   if (deliver_ipi(src_apic, dest_apic, icr->vec, icr->del_mode) == -1) {
+                       PrintError("apic: Error: Could not deliver IPI\n");
+                       v3_unlock(dest_apic->lock);
+                       goto route_ipi_out_bad;
                    }
+                   v3_unlock(dest_apic->lock);
                }
-           }   
-
-           break;
+               
+           }
        }
+           break;
        default:
-           PrintError("Error routing IPI, invalid Mode (%d)\n", icr->dst_shorthand);
-           return -1;
+           PrintError("apic: Error routing IPI, invalid Mode (%d)\n", icr->dst_shorthand);
+           goto route_ipi_out_bad;
     }
-    
 
+
+    // route_ipi_out_good:
+    //v3_unlock(apic_dev->ipi_lock);  
     return 0;
-}
 
+ route_ipi_out_bad:
+    //v3_unlock(apic_dev->ipi_lock);  
+    return -1;
+}
 
 
+// External function, expected to acquire lock on apic
 static int apic_read(struct guest_info * core, addr_t guest_addr, void * dst, uint_t length, void * priv_data) {
     struct apic_dev_state * apic_dev = (struct apic_dev_state *)(priv_data);
     struct apic_state * apic = &(apic_dev->apics[core->cpu_id]);
@@ -775,6 +1020,7 @@ static int apic_read(struct guest_info * core, addr_t guest_addr, void * dst, ui
     struct apic_msr * msr = (struct apic_msr *)&(apic->base_addr_msr.value);
     uint32_t val = 0;
 
+    v3_lock(apic->lock);
 
     PrintDebug("apic %u: core %u: at %p: Read apic address space (%p)\n",
               apic->lapic_id.val, core->cpu_id, apic, (void *)guest_addr);
@@ -783,7 +1029,7 @@ static int apic_read(struct guest_info * core, addr_t guest_addr, void * dst, ui
        PrintError("apic %u: core %u: Read from APIC address space with disabled APIC, apic msr=0x%llx\n",
                   apic->lapic_id.val, core->cpu_id, apic->base_addr_msr.value);
 
-       return -1;
+       goto apic_read_out_bad;
     }
 
 
@@ -996,7 +1242,7 @@ static int apic_read(struct guest_info * core, addr_t guest_addr, void * dst, ui
        default:
            PrintError("apic %u: core %u: Read from Unhandled APIC Register: %x (getting zero)\n", 
                       apic->lapic_id.val, core->cpu_id, (uint32_t)reg_addr);
-           return -1;
+           goto apic_read_out_bad;
     }
 
 
@@ -1019,13 +1265,20 @@ static int apic_read(struct guest_info * core, addr_t guest_addr, void * dst, ui
     } else {
        PrintError("apic %u: core %u: Invalid apic read length (%d)\n", 
                   apic->lapic_id.val, core->cpu_id, length);
-       return -1;
+       goto apic_read_out_bad;
     }
 
     PrintDebug("apic %u: core %u: Read finished (val=%x)\n", 
               apic->lapic_id.val, core->cpu_id, *(uint32_t *)dst);
 
+
+    // apic_read_out_good:
+    v3_unlock(apic->lock);
     return length;
+
+ apic_read_out_bad:
+    v3_unlock(apic->lock);
+    return -1;
 }
 
 
@@ -1039,23 +1292,26 @@ static int apic_write(struct guest_info * core, addr_t guest_addr, void * src, u
     struct apic_msr * msr = (struct apic_msr *)&(apic->base_addr_msr.value);
     uint32_t op_val = *(uint32_t *)src;
 
+
+    v3_lock(apic->lock);
+
     PrintDebug("apic %u: core %u: at %p and priv_data is at %p\n",
               apic->lapic_id.val, core->cpu_id, apic, priv_data);
 
-    PrintDebug("Write to address space (%p) (val=%x)\n", 
-              (void *)guest_addr, *(uint32_t *)src);
+    PrintDebug("apic %u: core %u: write to address space (%p) (val=%x)\n", 
+              apic->lapic_id.val, core->cpu_id, (void *)guest_addr, *(uint32_t *)src);
 
     if (msr->apic_enable == 0) {
        PrintError("apic %u: core %u: Write to APIC address space with disabled APIC, apic msr=0x%llx\n",
                   apic->lapic_id.val, core->cpu_id, apic->base_addr_msr.value);
-       return -1;
+       goto apic_write_out_bad;
     }
 
 
     if (length != 4) {
        PrintError("apic %u: core %u: Invalid apic write length (%d)\n", 
                   apic->lapic_id.val, length, core->cpu_id);
-       return -1;
+       goto apic_write_out_bad;
     }
 
     switch (reg_addr) {
@@ -1091,14 +1347,14 @@ static int apic_write(struct guest_info * core, addr_t guest_addr, void * src, u
 
            PrintError("apic %u: core %u: Attempting to write to read only register %p (error)\n", 
                       apic->lapic_id.val, core->cpu_id, (void *)reg_addr);
-           //  return -1;
+           //  goto apic_write_out_bad;
 
            break;
 
            // Data registers
        case APIC_ID_OFFSET:
-           PrintDebug("apic %u: core %u: my id is being changed to %u\n", 
-                      apic->lapic_id.val, core->cpu_id, op_val);
+           //V3_Print("apic %u: core %u: my id is being changed to %u\n", 
+           //       apic->lapic_id.val, core->cpu_id, op_val);
 
            apic->lapic_id.val = op_val;
            break;
@@ -1191,26 +1447,48 @@ static int apic_write(struct guest_info * core, addr_t guest_addr, void * src, u
 
            // Action Registers
        case EOI_OFFSET:
-           // do eoi
+           // do eoi (we already have the lock)
            apic_do_eoi(apic);
            break;
 
-       case INT_CMD_LO_OFFSET:
+       case INT_CMD_LO_OFFSET: {
+           // execute command (we already have the lock)
+
+           struct int_cmd_reg tmp_icr;
+
            apic->int_cmd.lo = op_val;
 
-           PrintDebug("apic %u: core %u: sending cmd 0x%llx to apic %u\n", 
-                      apic->lapic_id.val, core->cpu_id,
-                      apic->int_cmd.val, apic->int_cmd.dst);
+           tmp_icr=apic->int_cmd;
+
+           //      V3_Print("apic %u: core %u: sending cmd 0x%llx to apic %u\n", 
+           //       apic->lapic_id.val, core->cpu_id,
+           //       apic->int_cmd.val, apic->int_cmd.dst);
+
+           apic->in_icr=0;
 
-           if (route_ipi(core, apic_dev, apic, apic->int_cmd.val) == -1) { 
+           v3_unlock(apic->lock);
+
+           // route_ipi is responsible for locking apics, so we go in unlocked)
+           if (route_ipi(apic_dev, apic, &tmp_icr) == -1) { 
                PrintError("IPI Routing failure\n");
-               return -1;
+               goto apic_write_out_bad;
            }
 
+           //      v3_lock(apic->lock);  // expected for leaving this function
+
+       }
            break;
 
-       case INT_CMD_HI_OFFSET:
+       case INT_CMD_HI_OFFSET: {
+           // already have the lock
+           if (apic->in_icr) { 
+               PrintError("apic %u: core %u: writing command high=0x%x while in_icr=1\n", apic->lapic_id.val, core->cpu_id,apic->int_cmd.hi);
+           }
+
            apic->int_cmd.hi = op_val;
+           //V3_Print("apic %u: core %u: writing command high=0x%x\n", apic->lapic_id.val, core->cpu_id,apic->int_cmd.hi);
+           apic->in_icr=1;
+       }
            break;
 
 
@@ -1221,20 +1499,26 @@ static int apic_write(struct guest_info * core, addr_t guest_addr, void * src, u
            PrintError("apic %u: core %u: Write to Unhandled APIC Register: %x (ignored)\n", 
                       apic->lapic_id.val, core->cpu_id, (uint32_t)reg_addr);
 
-           return -1;
+           goto apic_write_out_bad;
     }
 
     PrintDebug("apic %u: core %u: Write finished\n", apic->lapic_id.val, core->cpu_id);
 
+    // apic_write_out_good:
+    v3_unlock(apic->lock);
     return length;
+
+ apic_write_out_bad:
+    v3_unlock(apic->lock);
+    return -1;
 }
 
 
 
 /* Interrupt Controller Functions */
 
-// returns 1 if an interrupt is pending, 0 otherwise
-static int apic_intr_pending(struct guest_info * core, void * private_data) {
+// internally used, expects caller to lock
+static int apic_intr_pending_nolock(struct guest_info * core, void * private_data) {
     struct apic_dev_state * apic_dev = (struct apic_dev_state *)(private_data);
     struct apic_state * apic = &(apic_dev->apics[core->cpu_id]); 
     int req_irq = get_highest_irr(apic);
@@ -1250,7 +1534,23 @@ static int apic_intr_pending(struct guest_info * core, void * private_data) {
     return 0;
 }
 
-static int apic_get_intr_number(struct guest_info * core, void * private_data) {
+// externally visible, so must lock itself
+static int apic_intr_pending(struct guest_info * core, void * private_data) {
+    struct apic_dev_state * apic_dev = (struct apic_dev_state *)(private_data);
+    struct apic_state * apic = &(apic_dev->apics[core->cpu_id]); 
+    int rc;
+
+    v3_lock(apic->lock);
+    
+    rc=apic_intr_pending_nolock(core,private_data);
+    
+    v3_unlock(apic->lock);
+
+    return rc;
+}
+
+// Internal - no lock
+static int apic_get_intr_number_nolock(struct guest_info * core, void * private_data) {
     struct apic_dev_state * apic_dev = (struct apic_dev_state *)(private_data);
     struct apic_state * apic = &(apic_dev->apics[core->cpu_id]); 
     int req_irq = get_highest_irr(apic);
@@ -1266,29 +1566,84 @@ static int apic_get_intr_number(struct guest_info * core, void * private_data) {
 }
 
 
-int v3_apic_raise_intr(struct v3_vm_info * vm, struct vm_device * dev, 
-                      uint32_t irq, uint32_t dst) {
-    struct apic_dev_state * apic_dev = (struct apic_dev_state *)(dev->private_data);
+// Externally visible, so must lock itself
+static int apic_get_intr_number(struct guest_info * core, void * private_data) {
+    struct apic_dev_state * apic_dev = (struct apic_dev_state *)(private_data);
+    struct apic_state * apic = &(apic_dev->apics[core->cpu_id]); 
+    int rc;
+
+    v3_lock(apic->lock);
+    
+    rc=apic_get_intr_number_nolock(core,private_data);
+
+    v3_unlock(apic->lock);
+
+    return rc;
+}
+
+
+//
+// Here there is no source APIC, so there is no need to lock it
+// Furthermore, the expectation is that route_ipi will lock the destiation apic
+int v3_apic_send_ipi(struct v3_vm_info * vm, struct v3_gen_ipi * ipi, void * dev_data) {
+    struct apic_dev_state * apic_dev = (struct apic_dev_state *)
+       (((struct vm_device *)dev_data)->private_data);
+    struct int_cmd_reg tmp_icr;
+
+    // zero out all the fields
+    tmp_icr.val = 0;
+
+    tmp_icr.vec = ipi->vector;
+    tmp_icr.del_mode = ipi->mode;
+    tmp_icr.dst_mode = ipi->logical;
+    tmp_icr.trig_mode = ipi->trigger_mode;
+    tmp_icr.dst_shorthand = ipi->dst_shorthand;
+    tmp_icr.dst = ipi->dst;
+
+    // route_ipi is responsible for locking the destination apic
+    return route_ipi(apic_dev, NULL, &tmp_icr);
+}
+
+
+int v3_apic_raise_intr(struct v3_vm_info * vm, uint32_t irq, uint32_t dst, void * dev_data) {
+    struct apic_dev_state * apic_dev = (struct apic_dev_state *)
+       (((struct vm_device*)dev_data)->private_data);
     struct apic_state * apic = &(apic_dev->apics[dst]); 
+    int do_xcall;
 
-    activate_apic_irq(apic, irq);
+    PrintDebug("apic %u core ?: raising interrupt IRQ %u (dst = %u).\n", apic->lapic_id.val, irq, dst); 
 
-    if (V3_Get_CPU() != dst) {
-       v3_interrupt_cpu(vm, dst, 0);
+    v3_lock(apic->lock);
+
+    do_xcall=activate_apic_irq_nolock(apic, irq);
+
+    if (do_xcall<0) { 
+       PrintError("Failed to activate apic irq\n");
+       v3_unlock(apic->lock);
+       return -1;
     }
+    
+    if (do_xcall>0 && (V3_Get_CPU() != dst)) {
+#ifdef CONFIG_MULTITHREAD_OS
+       v3_interrupt_cpu(vm, dst, 0);
+#else
+       V3_ASSERT(0);
+#endif
 
+    }
+    v3_unlock(apic->lock);
     return 0;
 }
 
 
-
-static int apic_begin_irq(struct guest_info * core, void * private_data, int irq) {
+// internal - caller must lock
+static int apic_begin_irq_nolock(struct guest_info * core, void * private_data, int irq) {
     struct apic_dev_state * apic_dev = (struct apic_dev_state *)(private_data);
     struct apic_state * apic = &(apic_dev->apics[core->cpu_id]); 
     int major_offset = (irq & ~0x00000007) >> 3;
     int minor_offset = irq & 0x00000007;
-    uint8_t * req_location = apic->int_req_reg + major_offset;
-    uint8_t * svc_location = apic->int_svc_reg + major_offset;
+    uint8_t *req_location = apic->int_req_reg + major_offset;
+    uint8_t *svc_location = apic->int_svc_reg + major_offset;
     uint8_t flag = 0x01 << minor_offset;
 
     if (*req_location & flag) {
@@ -1298,18 +1653,33 @@ static int apic_begin_irq(struct guest_info * core, void * private_data, int irq
        *req_location &= ~flag;
     } else {
        // do nothing... 
-       PrintDebug("apic %u: core %u: begin irq for %d ignored since I don't own it\n",
-                  apic->lapic_id.val, info->cpu_id, irq);
+       //PrintDebug("apic %u: core %u: begin irq for %d ignored since I don't own it\n",
+       //         apic->lapic_id.val, core->cpu_id, irq);
     }
 
     return 0;
 }
 
+// Since this is called, externally, it should lock the apic
+static int apic_begin_irq(struct guest_info * core, void * private_data, int irq) {
+    struct apic_dev_state * apic_dev = (struct apic_dev_state *)(private_data);
+    struct apic_state * apic = &(apic_dev->apics[core->cpu_id]); 
+    int rc;
+
+    v3_lock(apic->lock);
+
+    rc=apic_begin_irq_nolock(core,private_data,irq);
+
+    v3_unlock(apic->lock);
+
+    return rc;
+}
 
 
 
 /* Timer Functions */
-static void apic_update_time(struct guest_info * core, 
+// Caller will lock the apic
+static void apic_update_time_nolock(struct guest_info * core, 
                             uint64_t cpu_cycles, uint64_t cpu_freq, 
                             void * priv_data) {
     struct apic_dev_state * apic_dev = (struct apic_dev_state *)(priv_data);
@@ -1379,16 +1749,16 @@ static void apic_update_time(struct guest_info * core,
 
        // raise irq
        PrintDebug("apic %u: core %u: Raising APIC Timer interrupt (periodic=%d) (icnt=%d) (div=%d)\n",
-                  apic->lapic_id.val, info->cpu_id,
+                  apic->lapic_id.val, core->cpu_id,
                   apic->tmr_vec_tbl.tmr_mode, apic->tmr_init_cnt, shift_num);
 
-       if (apic_intr_pending(core, priv_data)) {
+       if (apic_intr_pending_nolock(core, priv_data)) {
            PrintDebug("apic %u: core %u: Overriding pending IRQ %d\n", 
-                      apic->lapic_id.val, info->cpu_id, 
-                      apic_get_intr_number(info, priv_data));
+                      apic->lapic_id.val, core->cpu_id, 
+                      apic_get_intr_number(core, priv_data));
        }
 
-       if (activate_internal_irq(apic, APIC_TMR_INT) == -1) {
+       if (activate_internal_irq_nolock(apic, APIC_TMR_INT) == -1) {
            PrintError("apic %u: core %u: Could not raise Timer interrupt\n",
                       apic->lapic_id.val, core->cpu_id);
        }
@@ -1399,10 +1769,25 @@ static void apic_update_time(struct guest_info * core,
        }
     }
 
-
+    return;
 }
 
 
+static void apic_update_time(struct guest_info * core, 
+                            uint64_t cpu_cycles, uint64_t cpu_freq, 
+                            void * priv_data) {
+    struct apic_dev_state * apic_dev = (struct apic_dev_state *)(priv_data);
+    struct apic_state * apic = &(apic_dev->apics[core->cpu_id]); 
+
+    v3_lock(apic->lock);
+
+    apic_update_time_nolock(core,cpu_cycles,cpu_freq,priv_data);
+
+    v3_unlock(apic->lock);
+    
+    return;
+}
+
 static struct intr_ctrl_ops intr_ops = {
     .intr_pending = apic_intr_pending,
     .get_intr_number = apic_get_intr_number,
@@ -1410,36 +1795,46 @@ static struct intr_ctrl_ops intr_ops = {
 };
 
 
-static struct vm_timer_ops timer_ops = {
+static struct v3_timer_ops timer_ops = {
     .update_timer = apic_update_time,
 };
 
 
 
 
-static int apic_free(struct vm_device * dev) {
+static int apic_free(struct apic_dev_state * apic_dev) {
+    int i = 0;
+    struct v3_vm_info * vm = NULL;
+
+    for (i = 0; i < apic_dev->num_apics; i++) {
+       struct apic_state * apic = &(apic_dev->apics[i]);
+       struct guest_info * core = apic->core;
+       
+       vm = core->vm_info;
+
+       v3_remove_intr_controller(core, apic->controller_handle);
 
-    /* TODO: This should crosscall to force an unhook on each CPU */
+       if (apic->timer) {
+           v3_remove_timer(core, apic->timer);
+       }
 
-    //   struct apic_state * apic = (struct apic_state *)dev->private_data;
+       // unhook memory
 
-    v3_unhook_msr(dev->vm, BASE_ADDR_MSR);
+    }
 
+    v3_unhook_msr(vm, BASE_ADDR_MSR);
+
+    V3_Free(apic_dev);
     return 0;
 }
 
 
 static struct v3_device_ops dev_ops = {
-    .free = apic_free,
-    .reset = NULL,
-    .start = NULL,
-    .stop = NULL,
+    .free = (int (*)(void *))apic_free,
 };
 
 
 
-
-
 static int apic_init(struct v3_vm_info * vm, v3_cfg_tree_t * cfg) {
     char * dev_id = v3_cfg_val(cfg, "ID");
     struct apic_dev_state * apic_dev = NULL;
@@ -1452,10 +1847,13 @@ static int apic_init(struct v3_vm_info * vm, v3_cfg_tree_t * cfg) {
 
     apic_dev->num_apics = vm->num_cores;
 
-    struct vm_device * dev = v3_allocate_device(dev_id, &dev_ops, apic_dev);
+    //v3_lock_init(&(apic_dev->ipi_lock));
+
+    struct vm_device * dev = v3_add_device(vm, dev_id, &dev_ops, apic_dev);
 
-    if (v3_attach_device(vm, dev) == -1) {
+    if (dev == NULL) {
        PrintError("apic: Could not attach device %s\n", dev_id);
+       V3_Free(apic_dev);
        return -1;
     }
 
@@ -1468,9 +1866,15 @@ static int apic_init(struct v3_vm_info * vm, v3_cfg_tree_t * cfg) {
 
        init_apic_state(apic, i);
 
-       v3_register_intr_controller(core, &intr_ops, apic_dev);
+       apic->controller_handle = v3_register_intr_controller(core, &intr_ops, apic_dev);
 
-       v3_add_timer(core, &timer_ops, apic_dev);
+       apic->timer = v3_add_timer(core, &timer_ops, apic_dev);
+
+       if (apic->timer == NULL) {
+           PrintError("APIC: Failed to attach timer to core %d\n", i);
+           v3_remove_device(dev);
+           return -1;
+       }
 
        v3_hook_full_mem(vm, core->cpu_id, apic->base_addr, apic->base_addr + PAGE_SIZE_4KB, apic_read, apic_write, apic_dev);
 
@@ -1480,8 +1884,8 @@ static int apic_init(struct v3_vm_info * vm, v3_cfg_tree_t * cfg) {
 #ifdef CONFIG_DEBUG_APIC
     for (i = 0; i < vm->num_cores; i++) {
        struct apic_state * apic = &(apic_dev->apics[i]);
-       PrintDebug("apic: sanity check: apic %u (at %p) has id %u and msr value %llx\n",
-                  i, apic, apic->lapic_id.val, apic->base_addr_msr.value);
+       PrintDebug("apic: sanity check: apic %u (at %p) has id %u and msr value %llx and core at %p\n",
+                  i, apic, apic->lapic_id.val, apic->base_addr_msr.value,apic->core);
     }
 #endif