qom: move CPUClass.tcg_initialize to a global

55c3cee ("qom: Introduce CPUClass.tcg_initialize", 2017-10-24)
introduces a per-CPUClass bool that we check so that the target CPU
is initialized for TCG only once. This works well except when
we end up creating more than one CPUClass, in which case we end
up incorrectly initializing TCG more than once, i.e. once for
each CPUClass.

This can be replicated with:
  $ aarch64-softmmu/qemu-system-aarch64 -machine xlnx-zcu102 -smp 6 \
      -global driver=xlnx,,zynqmp,property=has_rpu,value=on
In this case the class name of the "RPUs" is prefixed by "cortex-r5-",
whereas the "regular" CPUs are prefixed by "cortex-a53-". This
results in two CPUClass instances being created.

Fix it by introducing a static variable, so that only the first
target CPU being initialized will initialize the target-dependent
part of TCG, regardless of CPUClass instances.

Fixes: 55c3ceef61fcf06fc98ddc752b7cce788ce7680b
Signed-off-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Alistair Francis <alistair.francis@xilinx.com>
Message-id: 1510343626-25861-2-git-send-email-cota@braap.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/exec.c b/exec.c
index 97a24a875e7ecf86a2d9ada02f99288bf59755ad..8b579c0cd9c740a86d7fc4b04f08467bebc092a4 100644 (file)
--- a/exec.c
+++ b/exec.c
@@ -792,11 +792,12 @@ void cpu_exec_initfn(CPUState *cpu)
 void cpu_exec_realizefn(CPUState *cpu, Error **errp)
 {
     CPUClass *cc = CPU_GET_CLASS(cpu);
+    static bool tcg_target_initialized;
 
     cpu_list_add(cpu);
 
-    if (tcg_enabled() && !cc->tcg_initialized) {
-        cc->tcg_initialized = true;
+    if (tcg_enabled() && !tcg_target_initialized) {
+        tcg_target_initialized = true;
         cc->tcg_initialize();
     }
 

diff --git a/include/qom/cpu.h b/include/qom/cpu.h
index fa4b0c9dba728e30ffe70d53db156383ca423792..c2fa15122811e844a9b4bddf1038762d7ef0788b 100644 (file)
--- a/include/qom/cpu.h
+++ b/include/qom/cpu.h
@@ -209,7 +209,6 @@ typedef struct CPUClass {
     /* Keep non-pointer data at the end to minimize holes.  */
     int gdb_num_core_regs;
     bool gdb_stop_before_watchpoint;
-    bool tcg_initialized;
 } CPUClass;
 
 #ifdef HOST_WORDS_BIGENDIAN