PPC: msgsnd instruction leads to assertion

[Kurban Mallachiev]

I tried to send doorbells (using msgsnd) between cores in guest OS. On QEMU v2.9.0 usage of msgsnd instruction leads to error:
ERROR: <...>/qemu-new/translate-common.c:34:tcg_handle_interrupt: assertion failed: (qemu_mutex_iothread_locked())

QEMU v2.8.0 works fine.

QEMU run options: qemu-system-ppc -serial stdio -M ppce500 -cpu e500mc -smp 2 -m 512M -kernel pok.elf

pok.elf attached

[Thomas Huth (th-huth)]

Could you please check whether this patch fixes the issue for you:

diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c
--- a/target/ppc/excp_helper.c
+++ b/target/ppc/excp_helper.c
@@ -17,6 +17,7 @@
  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  */
 #include "qemu/osdep.h"
+#include "qemu/main-loop.h"
 #include "cpu.h"
 #include "exec/helper-proto.h"
 #include "exec/exec-all.h"
@@ -1132,6 +1133,7 @@ void helper_msgsnd(target_ulong rb)
         return;
     }

+ qemu_mutex_lock_iothread();
     CPU_FOREACH(cs) {
         PowerPCCPU *cpu = POWERPC_CPU(cs);
         CPUPPCState *cenv = &cpu->env;
@@ -1141,5 +1143,6 @@ void helper_msgsnd(target_ulong rb)
             cpu_interrupt(cs, CPU_INTERRUPT_HARD);
         }
     }
+ qemu_mutex_unlock_iothread();
 }
 #endif

[Kurban Mallachiev (mallachiev)]

Yes, Thomas, this patch fixes the issue.

[Thomas Huth (th-huth)]

Fix has now been included:
http://git.qemu.org/?p=qemu.git;a=commitdiff;h=f1c29ebc51be77bd64178c8d