Use qemu-cfg to notify the BIOS of the location of the TSS range to
reserve in the e820 table, to avoid relying on hard coded values.

Signed-off-by: Jes Sorensen <address@hidden>

---
 hw/pc.c           |    5 +++++
 kvm.h             |    7 +++++++
 target-i386/kvm.c |    5 +++++
 3 files changed, 17 insertions(+)

Index: qemu/hw/pc.c
===================================================================
--- qemu.orig/hw/pc.c
+++ qemu/hw/pc.c
@@ -45,6 +45,7 @@
 #include "loader.h"
 #include "elf.h"
 #include "multiboot.h"
+#include "kvm.h"
 
 /* output Bochs bios info messages */
 //#define DEBUG_BIOS
@@ -59,6 +60,7 @@
 #define FW_CFG_ACPI_TABLES (FW_CFG_ARCH_LOCAL + 0)
 #define FW_CFG_SMBIOS_ENTRIES (FW_CFG_ARCH_LOCAL + 1)
 #define FW_CFG_IRQ0_OVERRIDE (FW_CFG_ARCH_LOCAL + 2)
+#define FW_CFG_E820_RESERVE (FW_CFG_ARCH_LOCAL + 3)
 
 #define MAX_IDE_BUS 2
 
@@ -66,6 +68,7 @@ static fdctrl_t *floppy_controller;
 static RTCState *rtc_state;
 static PITState *pit;
 static PCII440FXState *i440fx_state;
+struct fw_cfg_e820_reserve e820_reserve;
 
 typedef struct isa_irq_state {
     qemu_irq *i8259;
@@ -466,6 +469,8 @@ static void *bochs_bios_init(void)
     if (smbios_table)
         fw_cfg_add_bytes(fw_cfg, FW_CFG_SMBIOS_ENTRIES,
                          smbios_table, smbios_len);
+    fw_cfg_add_bytes(fw_cfg, FW_CFG_E820_RESERVE, (uint8_t *)&e820_reserve,
+                     sizeof(struct fw_cfg_e820_reserve));
 
     /* allocate memory for the NUMA channel: one (64bit) word for the number
      * of nodes, one word for each VCPU->node and one word for each node to
Index: qemu/kvm.h
===================================================================
--- qemu.orig/kvm.h
+++ qemu/kvm.h
@@ -96,6 +96,13 @@ void kvm_arch_reset_vcpu(CPUState *env);
 struct kvm_guest_debug;
 struct kvm_debug_exit_arch;
 
+struct fw_cfg_e820_reserve {
+    uint32_t addr;
+    uint32_t length;
+};
+
+extern struct fw_cfg_e820_reserve e820_reserve;
+
 struct kvm_sw_breakpoint {
     target_ulong pc;
     target_ulong saved_insn;
Index: qemu/target-i386/kvm.c
===================================================================
--- qemu.orig/target-i386/kvm.c
+++ qemu/target-i386/kvm.c
@@ -356,6 +356,11 @@ int kvm_arch_init(KVMState *s, int smp_c
      * as unavaible memory.  FIXME, need to ensure the e820 map deals with
      * this?
      */
+    /*
+     * Tell fw_cfg to notify the BIOS to reserve the range.
+     */
+    e820_reserve.addr = 0xfffbc000;
+    e820_reserve.length = 0x4000;
     return kvm_vm_ioctl(s, KVM_SET_TSS_ADDR, 0xfffbd000);
 }