Re: [PATCH v6 06/18] cpu: Assert DeviceClass::vmsd is NULL on user emulation

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Philippe Mathieu-Daudé (f4bug@amsat.org) wrote:
> Migration is specific to system emulation.
> 
> Restrict current DeviceClass::vmsd to sysemu using #ifdef'ry,
> and assert in cpu_exec_realizefn() that dc->vmsd not set under
> user emulation.
> 
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  cpu.c                  | 1 +
>  target/sh4/cpu.c       | 5 +++--
>  target/unicore32/cpu.c | 4 ++++
>  target/xtensa/cpu.c    | 4 +++-
>  4 files changed, 11 insertions(+), 3 deletions(-)
> 
> diff --git a/cpu.c b/cpu.c
> index bfbe5a66f95..4fed04219df 100644
> --- a/cpu.c
> +++ b/cpu.c
> @@ -138,6 +138,7 @@ void cpu_exec_realizefn(CPUState *cpu, Error **errp)
>  #endif /* CONFIG_TCG */
>  
>  #ifdef CONFIG_USER_ONLY
> +    assert(qdev_get_vmsd(DEVICE(cpu)) == NULL);

Why not make that:
   assert(qdev_get_vmsd(DEVICE(cpu)) == NULL ||
          qdev_get_vmsd(DEVICE(cpu)->unmigratable)

then you don't have to worry about the changes below.

Dave

>      assert(cc->vmsd == NULL);
>  #else
>      if (qdev_get_vmsd(DEVICE(cpu)) == NULL) {
> diff --git a/target/sh4/cpu.c b/target/sh4/cpu.c
> index ac65c88f1f8..35d4251aaf3 100644
> --- a/target/sh4/cpu.c
> +++ b/target/sh4/cpu.c
> @@ -218,10 +218,12 @@ static void superh_cpu_initfn(Object *obj)
>      env->movcal_backup_tail = &(env->movcal_backup);
>  }
>  
> +#ifndef CONFIG_USER_ONLY
>  static const VMStateDescription vmstate_sh_cpu = {
>      .name = "cpu",
>      .unmigratable = 1,
>  };
> +#endif
>  
>  #include "hw/core/tcg-cpu-ops.h"
>  
> @@ -257,12 +259,11 @@ static void superh_cpu_class_init(ObjectClass *oc, void *data)
>      cc->gdb_write_register = superh_cpu_gdb_write_register;
>  #ifndef CONFIG_USER_ONLY
>      cc->get_phys_page_debug = superh_cpu_get_phys_page_debug;
> +    dc->vmsd = &vmstate_sh_cpu;
>  #endif
>      cc->disas_set_info = superh_cpu_disas_set_info;
>  
>      cc->gdb_num_core_regs = 59;
> -
> -    dc->vmsd = &vmstate_sh_cpu;
>      cc->tcg_ops = &superh_tcg_ops;
>  }
>  
> diff --git a/target/unicore32/cpu.c b/target/unicore32/cpu.c
> index 0258884f845..a74ac7b6140 100644
> --- a/target/unicore32/cpu.c
> +++ b/target/unicore32/cpu.c
> @@ -115,10 +115,12 @@ static void uc32_cpu_initfn(Object *obj)
>  #endif
>  }
>  
> +#ifndef CONFIG_USER_ONLY
>  static const VMStateDescription vmstate_uc32_cpu = {
>      .name = "cpu",
>      .unmigratable = 1,
>  };
> +#endif
>  
>  #include "hw/core/tcg-cpu-ops.h"
>  
> @@ -146,7 +148,9 @@ static void uc32_cpu_class_init(ObjectClass *oc, void *data)
>      cc->dump_state = uc32_cpu_dump_state;
>      cc->set_pc = uc32_cpu_set_pc;
>      cc->get_phys_page_debug = uc32_cpu_get_phys_page_debug;
> +#ifndef CONFIG_USER_ONLY
>      dc->vmsd = &vmstate_uc32_cpu;
> +#endif
>      cc->tcg_ops = &uc32_tcg_ops;
>  }
>  
> diff --git a/target/xtensa/cpu.c b/target/xtensa/cpu.c
> index e2b2c7a71c1..a66527e2d45 100644
> --- a/target/xtensa/cpu.c
> +++ b/target/xtensa/cpu.c
> @@ -176,10 +176,12 @@ static void xtensa_cpu_initfn(Object *obj)
>  #endif
>  }
>  
> +#ifndef CONFIG_USER_ONLY
>  static const VMStateDescription vmstate_xtensa_cpu = {
>      .name = "cpu",
>      .unmigratable = 1,
>  };
> +#endif
>  
>  #include "hw/core/tcg-cpu-ops.h"
>  
> @@ -216,9 +218,9 @@ static void xtensa_cpu_class_init(ObjectClass *oc, void *data)
>      cc->gdb_stop_before_watchpoint = true;
>  #ifndef CONFIG_USER_ONLY
>      cc->get_phys_page_debug = xtensa_cpu_get_phys_page_debug;
> +    dc->vmsd = &vmstate_xtensa_cpu;
>  #endif
>      cc->disas_set_info = xtensa_cpu_disas_set_info;
> -    dc->vmsd = &vmstate_xtensa_cpu;
>      cc->tcg_ops = &xtensa_tcg_ops;
>  }
>  
> -- 
> 2.26.3
> 
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK