With cpu hotplug is implemented on LoongArch virt machine, reset
interface with hot-added CPU should be registered. Otherwise there
will be problem if system reboots after cpu is hot-added.

Now register reset interface with CPU plug callback, so that all
cold/hot added CPUs let their reset interface registered. And remove
reset interface with CPU unplug callback.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
---
 hw/loongarch/boot.c | 13 -------------
 hw/loongarch/virt.c |  2 ++
 2 files changed, 2 insertions(+), 13 deletions(-)

diff --git a/hw/loongarch/boot.c b/hw/loongarch/boot.c
index 5799b4c75c..a516415822 100644
--- a/hw/loongarch/boot.c
+++ b/hw/loongarch/boot.c
@@ -350,13 +350,6 @@ static int64_t load_kernel_info(struct loongarch_boot_info *info)
     return kernel_entry;
 }
 
-static void reset_load_elf(void *opaque)
-{
-    LoongArchCPU *cpu = opaque;
-
-    cpu_reset(CPU(cpu));
-}
-
 static void fw_cfg_add_kernel_info(struct loongarch_boot_info *info,
                                    FWCfgState *fw_cfg)
 {
@@ -439,12 +432,6 @@ static void loongarch_direct_kernel_boot(MachineState *ms,
 void loongarch_load_kernel(MachineState *ms, struct loongarch_boot_info *info)
 {
     LoongArchVirtMachineState *lvms = LOONGARCH_VIRT_MACHINE(ms);
-    int i;
-
-    /* register reset function */
-    for (i = 0; i < ms->smp.cpus; i++) {
-        qemu_register_reset(reset_load_elf, LOONGARCH_CPU(qemu_get_cpu(i)));
-    }
 
     info->kernel_filename = ms->kernel_filename;
     info->kernel_cmdline = ms->kernel_cmdline;
diff --git a/hw/loongarch/virt.c b/hw/loongarch/virt.c
index 31215b7785..bd5cff1f1e 100644
--- a/hw/loongarch/virt.c
+++ b/hw/loongarch/virt.c
@@ -1014,6 +1014,7 @@ static void virt_cpu_unplug(HotplugHandler *hotplug_dev,
     /* Notify acpi ged CPU removed */
     hotplug_handler_unplug(HOTPLUG_HANDLER(lvms->acpi_ged), dev, &error_abort);
 
+    qemu_unregister_resettable(OBJECT(dev));
     cpu_slot = virt_find_cpu_slot(MACHINE(lvms), cpu->phy_id);
     cpu_slot->cpu = NULL;
 }
@@ -1038,6 +1039,7 @@ static void virt_cpu_plug(HotplugHandler *hotplug_dev,
                              &error_abort);
     }
 
+    qemu_register_resettable(OBJECT(dev));
     cpu_slot = virt_find_cpu_slot(MACHINE(lvms), cpu->phy_id);
     cpu_slot->cpu = CPU(dev);
 }
-- 
2.39.3

在 2025/9/6 下午3:02, Bibo Mao 写道:
> With cpu hotplug is implemented on LoongArch virt machine, reset
> interface with hot-added CPU should be registered. Otherwise there
> will be problem if system reboots after cpu is hot-added.
>
> Now register reset interface with CPU plug callback, so that all
> cold/hot added CPUs let their reset interface registered. And remove
> reset interface with CPU unplug callback.
>
> Signed-off-by: Bibo Mao <maobibo@loongson.cn>
> Reviewed-by: Igor Mammedov <imammedo@redhat.com>
> ---
>   hw/loongarch/boot.c | 13 -------------
>   hw/loongarch/virt.c |  2 ++
>   2 files changed, 2 insertions(+), 13 deletions(-)
Tested-by: Song Gao <gaosong@loongson.cn>

Thanks.
Song Gao
> diff --git a/hw/loongarch/boot.c b/hw/loongarch/boot.c
> index 5799b4c75c..a516415822 100644
> --- a/hw/loongarch/boot.c
> +++ b/hw/loongarch/boot.c
> @@ -350,13 +350,6 @@ static int64_t load_kernel_info(struct loongarch_boot_info *info)
>       return kernel_entry;
>   }
>   
> -static void reset_load_elf(void *opaque)
> -{
> -    LoongArchCPU *cpu = opaque;
> -
> -    cpu_reset(CPU(cpu));
> -}
> -
>   static void fw_cfg_add_kernel_info(struct loongarch_boot_info *info,
>                                      FWCfgState *fw_cfg)
>   {
> @@ -439,12 +432,6 @@ static void loongarch_direct_kernel_boot(MachineState *ms,
>   void loongarch_load_kernel(MachineState *ms, struct loongarch_boot_info *info)
>   {
>       LoongArchVirtMachineState *lvms = LOONGARCH_VIRT_MACHINE(ms);
> -    int i;
> -
> -    /* register reset function */
> -    for (i = 0; i < ms->smp.cpus; i++) {
> -        qemu_register_reset(reset_load_elf, LOONGARCH_CPU(qemu_get_cpu(i)));
> -    }
>   
>       info->kernel_filename = ms->kernel_filename;
>       info->kernel_cmdline = ms->kernel_cmdline;
> diff --git a/hw/loongarch/virt.c b/hw/loongarch/virt.c
> index 31215b7785..bd5cff1f1e 100644
> --- a/hw/loongarch/virt.c
> +++ b/hw/loongarch/virt.c
> @@ -1014,6 +1014,7 @@ static void virt_cpu_unplug(HotplugHandler *hotplug_dev,
>       /* Notify acpi ged CPU removed */
>       hotplug_handler_unplug(HOTPLUG_HANDLER(lvms->acpi_ged), dev, &error_abort);
>   
> +    qemu_unregister_resettable(OBJECT(dev));
>       cpu_slot = virt_find_cpu_slot(MACHINE(lvms), cpu->phy_id);
>       cpu_slot->cpu = NULL;
>   }
> @@ -1038,6 +1039,7 @@ static void virt_cpu_plug(HotplugHandler *hotplug_dev,
>                                &error_abort);
>       }
>   
> +    qemu_register_resettable(OBJECT(dev));
>       cpu_slot = virt_find_cpu_slot(MACHINE(lvms), cpu->phy_id);
>       cpu_slot->cpu = CPU(dev);
>   }