Disallow startup with shadow paging + memory region outside 4GB boundary

[palacios.git] / palacios / src / palacios / svm_io.c

diff --git a/palacios/src/palacios/svm_io.c b/palacios/src/palacios/svm_io.c
index e273466..ff85d09 100644 (file)
--- a/palacios/src/palacios/svm_io.c
+++ b/palacios/src/palacios/svm_io.c
@@ -46,9 +46,19 @@ static int update_map(struct v3_vm_info * vm, uint16_t port, int hook_read, int
 
 
 int v3_init_svm_io_map(struct v3_vm_info * vm) {
+    void *temp;
+
     vm->io_map.update_map = update_map;
 
-    vm->io_map.arch_data = V3_VAddr(V3_AllocPages(3));
+    temp = V3_AllocPages(3);
+    
+    if (!temp) { 
+       PrintError("Cannot allocate io bitmap\n");
+       return -1;
+    }
+
+    vm->io_map.arch_data = V3_VAddr(temp);
+
     memset(vm->io_map.arch_data, 0xff, PAGE_SIZE_4KB * 3);
 
 
@@ -80,11 +90,10 @@ int v3_handle_svm_io_in(struct guest_info * core, struct svm_io_info * io_info)
     PrintDebug("IN of %d bytes on port %d (0x%x)\n", read_size, io_info->port, io_info->port);
 
     if (hook == NULL) {
-       PrintDebug("IN operation on unhooked IO port 0x%x\n", io_info->port);
+       PrintDebug("IN operation on unhooked IO port 0x%x - returning zero\n", io_info->port);
+       core->vm_regs.rax >>= 8*read_size;
+       core->vm_regs.rax <<= 8*read_size;
 
-       /* What are the HW semantics for an IN on an invalid port? 
-        *  Do we need to clear the register value or leave it untouched??? 
-        */
     } else {
        if (hook->read(core, io_info->port, &(core->vm_regs.rax), read_size, hook->priv_data) != read_size) {
            // not sure how we handle errors.....
@@ -207,10 +216,9 @@ int v3_handle_svm_io_ins(struct guest_info * core, struct svm_io_info * io_info)
        }
 
        if (hook == NULL) {
-           PrintDebug("INS operation on unhooked IO port 0x%x\n", io_info->port);
-           /* What are the HW semantics for an INS on an invalid port? 
-            *  Do we need to clear the memory region or leave it untouched??? 
-            */     
+           PrintDebug("INS operation on unhooked IO port 0x%x - returning zeros\n", io_info->port);
+           memset((char*)host_addr,0,read_size);
+           
        } else {
            if (hook->read(core, io_info->port, (char *)host_addr, read_size, hook->priv_data) != read_size) {
                // not sure how we handle errors.....
@@ -246,7 +254,7 @@ int v3_handle_svm_io_out(struct guest_info * core, struct svm_io_info * io_info)
     PrintDebug("OUT of %d bytes on  port %d (0x%x)\n", write_size, io_info->port, io_info->port);
 
     if (hook == NULL) {
-       PrintDebug("OUT operation on unhooked IO port 0x%x\n", io_info->port);
+       PrintDebug("OUT operation on unhooked IO port 0x%x - ignored\n", io_info->port);
     } else {
        if (hook->write(core, io_info->port, &(core->vm_regs.rax), write_size, hook->priv_data) != write_size) {
            // not sure how we handle errors.....
@@ -365,7 +373,7 @@ int v3_handle_svm_io_outs(struct guest_info * core, struct svm_io_info * io_info
        }
 
        if (hook == NULL) {
-           PrintDebug("OUTS operation on unhooked IO port 0x%x\n", io_info->port);
+           PrintDebug("OUTS operation on unhooked IO port 0x%x - ignored\n", io_info->port);
        } else {
            if (hook->write(core, io_info->port, (char*)host_addr, write_size, hook->priv_data) != write_size) {
                // not sure how we handle errors.....