[Qemu-devel] [PATCH] Fix vmmouse with -smp

[Qemu-devel] [PATCH] Fix vmmouse with -smp

[Anthony Liguori]

The vmport code is very broken for SMP guests.  It uses a global CPUState
that's initialized multiple times?  At any rate, since it needs to know CPU
registers for the current CPU in a PIO handler, it needs to use cpu_single_env.

This patch makes vmmouse when using -smp > 1

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

diff --git a/hw/pc.c b/hw/pc.c
index 4fec2d4..e126f92 100644
--- a/hw/pc.c
+++ b/hw/pc.c
@@ -748,9 +748,10 @@ static void pc_init1(int ram_size, int vga_ram_size,
         if (pci_enabled) {
             apic_init(env);
         }
-        vmport_init(env);
     }
 
+    vmport_init();
+
     /* allocate RAM */
     ram_addr = qemu_ram_alloc(ram_size);
     cpu_register_physical_memory(0, ram_size, ram_addr);
diff --git a/hw/pc.h b/hw/pc.h
index 9f83050..8626599 100644
--- a/hw/pc.h
+++ b/hw/pc.h
@@ -59,7 +59,7 @@ int pit_get_mode(PITState *pit, int channel);
 int pit_get_out(PITState *pit, int channel, int64_t current_time);
 
 /* vmport.c */
-void vmport_init(CPUState *env);
+void vmport_init(void);
 void vmport_register(unsigned char command, IOPortReadFunc *func, void *opaque);
 
 /* vmmouse.c */
diff --git a/hw/vmport.c b/hw/vmport.c
index 8044c9f..3655ad1 100644
--- a/hw/vmport.c
+++ b/hw/vmport.c
@@ -34,7 +34,6 @@
 
 typedef struct _VMPortState
 {
-    CPUState *env;
     IOPortReadFunc *func[VMPORT_ENTRIES];
     void *opaque[VMPORT_ENTRIES];
 } VMPortState;
@@ -53,14 +52,15 @@ void vmport_register(unsigned char command, IOPortReadFunc *func, void *opaque)
 static uint32_t vmport_ioport_read(void *opaque, uint32_t addr)
 {
     VMPortState *s = opaque;
+    CPUState *env = cpu_single_env;
     unsigned char command;
     uint32_t eax;
 
-    eax = s->env->regs[R_EAX];
+    eax = env->regs[R_EAX];
     if (eax != VMPORT_MAGIC)
         return eax;
 
-    command = s->env->regs[R_ECX];
+    command = env->regs[R_ECX];
     if (command >= VMPORT_ENTRIES)
         return eax;
     if (!s->func[command])
@@ -74,25 +74,23 @@ static uint32_t vmport_ioport_read(void *opaque, uint32_t addr)
 
 static uint32_t vmport_cmd_get_version(void *opaque, uint32_t addr)
 {
-    CPUState *env = opaque;
+    CPUState *env = cpu_single_env;
     env->regs[R_EBX] = VMPORT_MAGIC;
     return 6;
 }
 
 static uint32_t vmport_cmd_ram_size(void *opaque, uint32_t addr)
 {
-    CPUState *env = opaque;
+    CPUState *env = cpu_single_env;
     env->regs[R_EBX] = 0x1177;
     return ram_size;
 }
 
-void vmport_init(CPUState *env)
+void vmport_init(void)
 {
-    port_state.env = env;
-
     register_ioport_read(0x5658, 1, 4, vmport_ioport_read, &port_state);
 
     /* Register some generic port commands */
-    vmport_register(VMPORT_CMD_GETVERSION, vmport_cmd_get_version, env);
-    vmport_register(VMPORT_CMD_GETRAMSIZE, vmport_cmd_ram_size, env);
+    vmport_register(VMPORT_CMD_GETVERSION, vmport_cmd_get_version, NULL);
+    vmport_register(VMPORT_CMD_GETRAMSIZE, vmport_cmd_ram_size, NULL);
 }

[Qemu-devel] Re: [kvm-devel] [PATCH] Fix vmmouse with -smp

[Avi Kivity]

Anthony Liguori wrote:
> The vmport code is very broken for SMP guests.  It uses a global CPUState
> that's initialized multiple times?  At any rate, since it needs to know CPU
> registers for the current CPU in a PIO handler, it needs to use cpu_single_env.
>
> This patch makes vmmouse when using -smp > 1
>
>   

Applied to kvm's qemu, thanks.

-- 
Any sufficiently difficult bug is indistinguishable from a feature.