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[PATCH v4 1/3] LongArch: KVM: Add DMSINTC device support

Song Gao posted 3 patches 1 month, 3 weeks ago
There is a newer version of this series
[PATCH v4 1/3] LongArch: KVM: Add DMSINTC device support
Posted by Song Gao 1 month, 3 weeks ago 
Add device model for DMSINTC interrupt controller, implement basic
create/destroy/set_attr interfaces, and register device model to kvm
device table.

Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
---
 arch/loongarch/include/asm/kvm_dmsintc.h |  21 +++++
 arch/loongarch/include/asm/kvm_host.h    |   3 +
 arch/loongarch/include/uapi/asm/kvm.h    |   4 +
 arch/loongarch/kvm/Makefile              |   1 +
 arch/loongarch/kvm/intc/dmsintc.c        | 110 +++++++++++++++++++++++
 arch/loongarch/kvm/main.c                |   5 ++
 include/uapi/linux/kvm.h                 |   2 +
 7 files changed, 146 insertions(+)
 create mode 100644 arch/loongarch/include/asm/kvm_dmsintc.h
 create mode 100644 arch/loongarch/kvm/intc/dmsintc.c

diff --git a/arch/loongarch/include/asm/kvm_dmsintc.h b/arch/loongarch/include/asm/kvm_dmsintc.h
new file mode 100644
index 000000000000..1d4f66996f3c
--- /dev/null
+++ b/arch/loongarch/include/asm/kvm_dmsintc.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2025 Loongson Technology Corporation Limited
+ */
+
+#ifndef __ASM_KVM_DMSINTC_H
+#define __ASM_KVM_DMSINTC_H
+
+
+struct loongarch_dmsintc  {
+	struct kvm *kvm;
+	uint64_t msg_addr_base;
+	uint64_t msg_addr_size;
+};
+
+struct dmsintc_state {
+	atomic64_t  vector_map[4];
+};
+
+int kvm_loongarch_register_dmsintc_device(void);
+#endif
diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h
index e4fe5b8e8149..5e9e2af7312f 100644
--- a/arch/loongarch/include/asm/kvm_host.h
+++ b/arch/loongarch/include/asm/kvm_host.h
@@ -22,6 +22,7 @@
 #include <asm/kvm_ipi.h>
 #include <asm/kvm_eiointc.h>
 #include <asm/kvm_pch_pic.h>
+#include <asm/kvm_dmsintc.h>
 #include <asm/loongarch.h>
 
 #define __KVM_HAVE_ARCH_INTC_INITIALIZED
@@ -134,6 +135,7 @@ struct kvm_arch {
 	struct loongarch_ipi *ipi;
 	struct loongarch_eiointc *eiointc;
 	struct loongarch_pch_pic *pch_pic;
+	struct loongarch_dmsintc *dmsintc;
 };
 
 #define CSR_MAX_NUMS		0x800
@@ -244,6 +246,7 @@ struct kvm_vcpu_arch {
 	struct kvm_mp_state mp_state;
 	/* ipi state */
 	struct ipi_state ipi_state;
+	struct dmsintc_state dmsintc_state;
 	/* cpucfg */
 	u32 cpucfg[KVM_MAX_CPUCFG_REGS];
 
diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h
index de6c3f18e40a..0a370d018b08 100644
--- a/arch/loongarch/include/uapi/asm/kvm.h
+++ b/arch/loongarch/include/uapi/asm/kvm.h
@@ -154,4 +154,8 @@ struct kvm_iocsr_entry {
 #define KVM_DEV_LOONGARCH_PCH_PIC_GRP_CTRL	        0x40000006
 #define KVM_DEV_LOONGARCH_PCH_PIC_CTRL_INIT	        0
 
+#define KVM_DEV_LOONGARCH_DMSINTC_CTRL			0x40000007
+#define KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_BASE		0x0
+#define KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_SIZE		0x1
+
 #endif /* __UAPI_ASM_LOONGARCH_KVM_H */
diff --git a/arch/loongarch/kvm/Makefile b/arch/loongarch/kvm/Makefile
index cb41d9265662..6e184e24443c 100644
--- a/arch/loongarch/kvm/Makefile
+++ b/arch/loongarch/kvm/Makefile
@@ -19,6 +19,7 @@ kvm-y += vm.o
 kvm-y += intc/ipi.o
 kvm-y += intc/eiointc.o
 kvm-y += intc/pch_pic.o
+kvm-y += intc/dmsintc.o
 kvm-y += irqfd.o
 
 CFLAGS_exit.o	+= $(call cc-disable-warning, override-init)
diff --git a/arch/loongarch/kvm/intc/dmsintc.c b/arch/loongarch/kvm/intc/dmsintc.c
new file mode 100644
index 000000000000..3fdea81a08c8
--- /dev/null
+++ b/arch/loongarch/kvm/intc/dmsintc.c
@@ -0,0 +1,110 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2025 Loongson Technology Corporation Limited
+ */
+
+#include <linux/kvm_host.h>
+#include <asm/kvm_dmsintc.h>
+#include <asm/kvm_vcpu.h>
+
+static int kvm_dmsintc_ctrl_access(struct kvm_device *dev,
+				struct kvm_device_attr *attr,
+				bool is_write)
+{
+	int addr = attr->attr;
+	void __user *data;
+	struct loongarch_dmsintc *s = dev->kvm->arch.dmsintc;
+	u64 tmp;
+
+	data = (void __user *)attr->addr;
+	switch (addr) {
+	case KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_BASE:
+		if (is_write) {
+			if (copy_from_user(&tmp, data, sizeof(s->msg_addr_base)))
+				return -EFAULT;
+			if (s->msg_addr_base) {
+				/* Duplicate setting are not allowed. */
+				return -EFAULT;
+			}
+			if ((tmp & (BIT(AVEC_CPU_SHIFT) - 1)) == 0)
+				s->msg_addr_base = tmp;
+			else
+				return  -EFAULT;
+		}
+		break;
+	case KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_SIZE:
+		if (is_write) {
+			if (copy_from_user(&tmp, data, sizeof(s->msg_addr_size)))
+				return -EFAULT;
+			if (s->msg_addr_size) {
+				/*Duplicate setting are not allowed. */
+				return -EFAULT;
+			}
+			s->msg_addr_size = tmp;
+		}
+		break;
+	default:
+		kvm_err("%s: unknown dmsintc register, addr = %d\n", __func__, addr);
+		return -ENXIO;
+	}
+
+	return 0;
+}
+
+static int kvm_dmsintc_set_attr(struct kvm_device *dev,
+			struct kvm_device_attr *attr)
+{
+	switch (attr->group) {
+	case KVM_DEV_LOONGARCH_DMSINTC_CTRL:
+		return kvm_dmsintc_ctrl_access(dev, attr, true);
+	default:
+		kvm_err("%s: unknown group (%d)\n", __func__, attr->group);
+		return -EINVAL;
+	}
+}
+
+static int kvm_dmsintc_create(struct kvm_device *dev, u32 type)
+{
+	struct kvm *kvm;
+	struct loongarch_dmsintc *s;
+
+	if (!dev) {
+		kvm_err("%s: kvm_device ptr is invalid!\n", __func__);
+		return -EINVAL;
+	}
+
+	kvm = dev->kvm;
+	if (kvm->arch.dmsintc) {
+		kvm_err("%s: LoongArch DMSINTC has already been created!\n", __func__);
+		return -EINVAL;
+	}
+
+	s = kzalloc(sizeof(struct loongarch_dmsintc), GFP_KERNEL);
+	if (!s)
+		return -ENOMEM;
+
+	s->kvm = kvm;
+	kvm->arch.dmsintc = s;
+	return 0;
+}
+
+static void kvm_dmsintc_destroy(struct kvm_device *dev)
+{
+
+	if (!dev || !dev->kvm || !dev->kvm->arch.dmsintc)
+		return;
+
+	kfree(dev->kvm->arch.dmsintc);
+}
+
+static struct kvm_device_ops kvm_dmsintc_dev_ops = {
+	.name = "kvm-loongarch-dmsintc",
+	.create = kvm_dmsintc_create,
+	.destroy = kvm_dmsintc_destroy,
+	.set_attr = kvm_dmsintc_set_attr,
+};
+
+int kvm_loongarch_register_dmsintc_device(void)
+{
+	return kvm_register_device_ops(&kvm_dmsintc_dev_ops, KVM_DEV_TYPE_LOONGARCH_DMSINTC);
+}
diff --git a/arch/loongarch/kvm/main.c b/arch/loongarch/kvm/main.c
index 80ea63d465b8..2e26d4fd9000 100644
--- a/arch/loongarch/kvm/main.c
+++ b/arch/loongarch/kvm/main.c
@@ -408,6 +408,11 @@ static int kvm_loongarch_env_init(void)
 
 	/* Register LoongArch PCH-PIC interrupt controller interface. */
 	ret = kvm_loongarch_register_pch_pic_device();
+	if (ret)
+		return ret;
+
+	/* Register LoongArch DMSINTC interrupt contrroller interface */
+	ret = kvm_loongarch_register_dmsintc_device();
 
 	return ret;
 }
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index dddb781b0507..7c56e7e36265 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1209,6 +1209,8 @@ enum kvm_device_type {
 #define KVM_DEV_TYPE_LOONGARCH_EIOINTC	KVM_DEV_TYPE_LOONGARCH_EIOINTC
 	KVM_DEV_TYPE_LOONGARCH_PCHPIC,
 #define KVM_DEV_TYPE_LOONGARCH_PCHPIC	KVM_DEV_TYPE_LOONGARCH_PCHPIC
+	KVM_DEV_TYPE_LOONGARCH_DMSINTC,
+#define KVM_DEV_TYPE_LOONGARCH_DMSINTC   KVM_DEV_TYPE_LOONGARCH_DMSINTC
 
 	KVM_DEV_TYPE_MAX,
 
-- 
2.39.3
Re: [PATCH v4 1/3] LongArch: KVM: Add DMSINTC device support
Posted by Bibo Mao 1 month, 2 weeks ago 

On 2025/12/18 下午7:18, Song Gao wrote:
> Add device model for DMSINTC interrupt controller, implement basic
> create/destroy/set_attr interfaces, and register device model to kvm
> device table.
> 
> Reviewed-by: Bibo Mao <maobibo@loongson.cn>
> Signed-off-by: Song Gao <gaosong@loongson.cn>
> ---
>   arch/loongarch/include/asm/kvm_dmsintc.h |  21 +++++
>   arch/loongarch/include/asm/kvm_host.h    |   3 +
>   arch/loongarch/include/uapi/asm/kvm.h    |   4 +
>   arch/loongarch/kvm/Makefile              |   1 +
>   arch/loongarch/kvm/intc/dmsintc.c        | 110 +++++++++++++++++++++++
>   arch/loongarch/kvm/main.c                |   5 ++
>   include/uapi/linux/kvm.h                 |   2 +
>   7 files changed, 146 insertions(+)
>   create mode 100644 arch/loongarch/include/asm/kvm_dmsintc.h
>   create mode 100644 arch/loongarch/kvm/intc/dmsintc.c
> 
> diff --git a/arch/loongarch/include/asm/kvm_dmsintc.h b/arch/loongarch/include/asm/kvm_dmsintc.h
> new file mode 100644
> index 000000000000..1d4f66996f3c
> --- /dev/null
> +++ b/arch/loongarch/include/asm/kvm_dmsintc.h
> @@ -0,0 +1,21 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2025 Loongson Technology Corporation Limited
> + */
> +
> +#ifndef __ASM_KVM_DMSINTC_H
> +#define __ASM_KVM_DMSINTC_H
> +
> +
> +struct loongarch_dmsintc  {
> +	struct kvm *kvm;
> +	uint64_t msg_addr_base;
> +	uint64_t msg_addr_size;
> +};
> +
> +struct dmsintc_state {
> +	atomic64_t  vector_map[4];
> +};
> +
> +int kvm_loongarch_register_dmsintc_device(void);
> +#endif
> diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h
> index e4fe5b8e8149..5e9e2af7312f 100644
> --- a/arch/loongarch/include/asm/kvm_host.h
> +++ b/arch/loongarch/include/asm/kvm_host.h
> @@ -22,6 +22,7 @@
>   #include <asm/kvm_ipi.h>
>   #include <asm/kvm_eiointc.h>
>   #include <asm/kvm_pch_pic.h>
> +#include <asm/kvm_dmsintc.h>
>   #include <asm/loongarch.h>
>   
>   #define __KVM_HAVE_ARCH_INTC_INITIALIZED
> @@ -134,6 +135,7 @@ struct kvm_arch {
>   	struct loongarch_ipi *ipi;
>   	struct loongarch_eiointc *eiointc;
>   	struct loongarch_pch_pic *pch_pic;
> +	struct loongarch_dmsintc *dmsintc;
>   };
>   
>   #define CSR_MAX_NUMS		0x800
> @@ -244,6 +246,7 @@ struct kvm_vcpu_arch {
>   	struct kvm_mp_state mp_state;
>   	/* ipi state */
>   	struct ipi_state ipi_state;
> +	struct dmsintc_state dmsintc_state;
>   	/* cpucfg */
>   	u32 cpucfg[KVM_MAX_CPUCFG_REGS];
>   
> diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h
> index de6c3f18e40a..0a370d018b08 100644
> --- a/arch/loongarch/include/uapi/asm/kvm.h
> +++ b/arch/loongarch/include/uapi/asm/kvm.h
> @@ -154,4 +154,8 @@ struct kvm_iocsr_entry {
>   #define KVM_DEV_LOONGARCH_PCH_PIC_GRP_CTRL	        0x40000006
>   #define KVM_DEV_LOONGARCH_PCH_PIC_CTRL_INIT	        0
>   
> +#define KVM_DEV_LOONGARCH_DMSINTC_CTRL			0x40000007
> +#define KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_BASE		0x0
> +#define KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_SIZE		0x1
> +
>   #endif /* __UAPI_ASM_LOONGARCH_KVM_H */
> diff --git a/arch/loongarch/kvm/Makefile b/arch/loongarch/kvm/Makefile
> index cb41d9265662..6e184e24443c 100644
> --- a/arch/loongarch/kvm/Makefile
> +++ b/arch/loongarch/kvm/Makefile
> @@ -19,6 +19,7 @@ kvm-y += vm.o
>   kvm-y += intc/ipi.o
>   kvm-y += intc/eiointc.o
>   kvm-y += intc/pch_pic.o
> +kvm-y += intc/dmsintc.o
>   kvm-y += irqfd.o
>   
>   CFLAGS_exit.o	+= $(call cc-disable-warning, override-init)
> diff --git a/arch/loongarch/kvm/intc/dmsintc.c b/arch/loongarch/kvm/intc/dmsintc.c
> new file mode 100644
> index 000000000000..3fdea81a08c8
> --- /dev/null
> +++ b/arch/loongarch/kvm/intc/dmsintc.c
> @@ -0,0 +1,110 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2025 Loongson Technology Corporation Limited
> + */
> +
> +#include <linux/kvm_host.h>
> +#include <asm/kvm_dmsintc.h>
> +#include <asm/kvm_vcpu.h>
> +
> +static int kvm_dmsintc_ctrl_access(struct kvm_device *dev,
> +				struct kvm_device_attr *attr,
> +				bool is_write)
> +{
> +	int addr = attr->attr;
> +	void __user *data;
> +	struct loongarch_dmsintc *s = dev->kvm->arch.dmsintc;
> +	u64 tmp;
> +
> +	data = (void __user *)attr->addr;
> +	switch (addr) {
> +	case KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_BASE:
> +		if (is_write) {
> +			if (copy_from_user(&tmp, data, sizeof(s->msg_addr_base)))
> +				return -EFAULT;
> +			if (s->msg_addr_base) {
> +				/* Duplicate setting are not allowed. */
> +				return -EFAULT;
> +			}
> +			if ((tmp & (BIT(AVEC_CPU_SHIFT) - 1)) == 0)
> +				s->msg_addr_base = tmp;
> +			else
> +				return  -EFAULT;
> +		}
> +		break;
> +	case KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_SIZE:
> +		if (is_write) {
> +			if (copy_from_user(&tmp, data, sizeof(s->msg_addr_size)))
> +				return -EFAULT;
> +			if (s->msg_addr_size) {
> +				/*Duplicate setting are not allowed. */
> +				return -EFAULT;
> +			}
> +			s->msg_addr_size = tmp;
> +		}
> +		break;
> +	default:
> +		kvm_err("%s: unknown dmsintc register, addr = %d\n", __func__, addr);
> +		return -ENXIO;
> +	}
> +
> +	return 0;
> +}
> +
> +static int kvm_dmsintc_set_attr(struct kvm_device *dev,
> +			struct kvm_device_attr *attr)
> +{
> +	switch (attr->group) {
> +	case KVM_DEV_LOONGARCH_DMSINTC_CTRL:
> +		return kvm_dmsintc_ctrl_access(dev, attr, true);
> +	default:
> +		kvm_err("%s: unknown group (%d)\n", __func__, attr->group);
> +		return -EINVAL;
> +	}
> +}
> +
> +static int kvm_dmsintc_create(struct kvm_device *dev, u32 type)
> +{
> +	struct kvm *kvm;
> +	struct loongarch_dmsintc *s;
> +
> +	if (!dev) {
> +		kvm_err("%s: kvm_device ptr is invalid!\n", __func__);
> +		return -EINVAL;
> +	}
> +
> +	kvm = dev->kvm;
> +	if (kvm->arch.dmsintc) {
> +		kvm_err("%s: LoongArch DMSINTC has already been created!\n", __func__);
> +		return -EINVAL;
> +	}
> +
> +	s = kzalloc(sizeof(struct loongarch_dmsintc), GFP_KERNEL);
> +	if (!s)
> +		return -ENOMEM;
> +
> +	s->kvm = kvm;
> +	kvm->arch.dmsintc = s;
> +	return 0;
> +}
> +
> +static void kvm_dmsintc_destroy(struct kvm_device *dev)
> +{
> +
> +	if (!dev || !dev->kvm || !dev->kvm->arch.dmsintc)
> +		return;
> +
> +	kfree(dev->kvm->arch.dmsintc);
> +}
> +
> +static struct kvm_device_ops kvm_dmsintc_dev_ops = {
> +	.name = "kvm-loongarch-dmsintc",
> +	.create = kvm_dmsintc_create,
> +	.destroy = kvm_dmsintc_destroy,
> +	.set_attr = kvm_dmsintc_set_attr,
> +};
> +
> +int kvm_loongarch_register_dmsintc_device(void)
> +{
> +	return kvm_register_device_ops(&kvm_dmsintc_dev_ops, KVM_DEV_TYPE_LOONGARCH_DMSINTC);
> +}
> diff --git a/arch/loongarch/kvm/main.c b/arch/loongarch/kvm/main.c
> index 80ea63d465b8..2e26d4fd9000 100644
> --- a/arch/loongarch/kvm/main.c
> +++ b/arch/loongarch/kvm/main.c
> @@ -408,6 +408,11 @@ static int kvm_loongarch_env_init(void)
>   
>   	/* Register LoongArch PCH-PIC interrupt controller interface. */
>   	ret = kvm_loongarch_register_pch_pic_device();
> +	if (ret)
> +		return ret;
> +
> +	/* Register LoongArch DMSINTC interrupt contrroller interface */
> +	ret = kvm_loongarch_register_dmsintc_device();
I think it will be better if cpu_has_msgint() is added, in theory 
dmsintc cannot be added on 3C5000 host machine, and KVM cannot prevent 
VMM executing FUZZ ioctl commands.

Regards
Bibo Mao
>   
>   	return ret;
>   }
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index dddb781b0507..7c56e7e36265 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -1209,6 +1209,8 @@ enum kvm_device_type {
>   #define KVM_DEV_TYPE_LOONGARCH_EIOINTC	KVM_DEV_TYPE_LOONGARCH_EIOINTC
>   	KVM_DEV_TYPE_LOONGARCH_PCHPIC,
>   #define KVM_DEV_TYPE_LOONGARCH_PCHPIC	KVM_DEV_TYPE_LOONGARCH_PCHPIC
> +	KVM_DEV_TYPE_LOONGARCH_DMSINTC,
> +#define KVM_DEV_TYPE_LOONGARCH_DMSINTC   KVM_DEV_TYPE_LOONGARCH_DMSINTC
>   
>   	KVM_DEV_TYPE_MAX,
>   
>
Re: [PATCH v4 1/3] LongArch: KVM: Add DMSINTC device support
Posted by gaosong 1 month, 2 weeks ago 
在 2025/12/25 下午2:48, Bibo Mao 写道:
>
>
> On 2025/12/18 下午7:18, Song Gao wrote:
>> Add device model for DMSINTC interrupt controller, implement basic
>> create/destroy/set_attr interfaces, and register device model to kvm
>> device table.
>>
>> Reviewed-by: Bibo Mao <maobibo@loongson.cn>
>> Signed-off-by: Song Gao <gaosong@loongson.cn>
>> ---
>>   arch/loongarch/include/asm/kvm_dmsintc.h |  21 +++++
>>   arch/loongarch/include/asm/kvm_host.h    |   3 +
>>   arch/loongarch/include/uapi/asm/kvm.h    |   4 +
>>   arch/loongarch/kvm/Makefile              |   1 +
>>   arch/loongarch/kvm/intc/dmsintc.c        | 110 +++++++++++++++++++++++
>>   arch/loongarch/kvm/main.c                |   5 ++
>>   include/uapi/linux/kvm.h                 |   2 +
>>   7 files changed, 146 insertions(+)
>>   create mode 100644 arch/loongarch/include/asm/kvm_dmsintc.h
>>   create mode 100644 arch/loongarch/kvm/intc/dmsintc.c
>>
>> diff --git a/arch/loongarch/include/asm/kvm_dmsintc.h 
>> b/arch/loongarch/include/asm/kvm_dmsintc.h
>> new file mode 100644
>> index 000000000000..1d4f66996f3c
>> --- /dev/null
>> +++ b/arch/loongarch/include/asm/kvm_dmsintc.h
>> @@ -0,0 +1,21 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * Copyright (C) 2025 Loongson Technology Corporation Limited
>> + */
>> +
>> +#ifndef __ASM_KVM_DMSINTC_H
>> +#define __ASM_KVM_DMSINTC_H
>> +
>> +
>> +struct loongarch_dmsintc  {
>> +    struct kvm *kvm;
>> +    uint64_t msg_addr_base;
>> +    uint64_t msg_addr_size;
>> +};
>> +
>> +struct dmsintc_state {
>> +    atomic64_t  vector_map[4];
>> +};
>> +
>> +int kvm_loongarch_register_dmsintc_device(void);
>> +#endif
>> diff --git a/arch/loongarch/include/asm/kvm_host.h 
>> b/arch/loongarch/include/asm/kvm_host.h
>> index e4fe5b8e8149..5e9e2af7312f 100644
>> --- a/arch/loongarch/include/asm/kvm_host.h
>> +++ b/arch/loongarch/include/asm/kvm_host.h
>> @@ -22,6 +22,7 @@
>>   #include <asm/kvm_ipi.h>
>>   #include <asm/kvm_eiointc.h>
>>   #include <asm/kvm_pch_pic.h>
>> +#include <asm/kvm_dmsintc.h>
>>   #include <asm/loongarch.h>
>>     #define __KVM_HAVE_ARCH_INTC_INITIALIZED
>> @@ -134,6 +135,7 @@ struct kvm_arch {
>>       struct loongarch_ipi *ipi;
>>       struct loongarch_eiointc *eiointc;
>>       struct loongarch_pch_pic *pch_pic;
>> +    struct loongarch_dmsintc *dmsintc;
>>   };
>>     #define CSR_MAX_NUMS        0x800
>> @@ -244,6 +246,7 @@ struct kvm_vcpu_arch {
>>       struct kvm_mp_state mp_state;
>>       /* ipi state */
>>       struct ipi_state ipi_state;
>> +    struct dmsintc_state dmsintc_state;
>>       /* cpucfg */
>>       u32 cpucfg[KVM_MAX_CPUCFG_REGS];
>>   diff --git a/arch/loongarch/include/uapi/asm/kvm.h 
>> b/arch/loongarch/include/uapi/asm/kvm.h
>> index de6c3f18e40a..0a370d018b08 100644
>> --- a/arch/loongarch/include/uapi/asm/kvm.h
>> +++ b/arch/loongarch/include/uapi/asm/kvm.h
>> @@ -154,4 +154,8 @@ struct kvm_iocsr_entry {
>>   #define KVM_DEV_LOONGARCH_PCH_PIC_GRP_CTRL 0x40000006
>>   #define KVM_DEV_LOONGARCH_PCH_PIC_CTRL_INIT            0
>>   +#define KVM_DEV_LOONGARCH_DMSINTC_CTRL            0x40000007
>> +#define KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_BASE        0x0
>> +#define KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_SIZE        0x1
>> +
>>   #endif /* __UAPI_ASM_LOONGARCH_KVM_H */
>> diff --git a/arch/loongarch/kvm/Makefile b/arch/loongarch/kvm/Makefile
>> index cb41d9265662..6e184e24443c 100644
>> --- a/arch/loongarch/kvm/Makefile
>> +++ b/arch/loongarch/kvm/Makefile
>> @@ -19,6 +19,7 @@ kvm-y += vm.o
>>   kvm-y += intc/ipi.o
>>   kvm-y += intc/eiointc.o
>>   kvm-y += intc/pch_pic.o
>> +kvm-y += intc/dmsintc.o
>>   kvm-y += irqfd.o
>>     CFLAGS_exit.o    += $(call cc-disable-warning, override-init)
>> diff --git a/arch/loongarch/kvm/intc/dmsintc.c 
>> b/arch/loongarch/kvm/intc/dmsintc.c
>> new file mode 100644
>> index 000000000000..3fdea81a08c8
>> --- /dev/null
>> +++ b/arch/loongarch/kvm/intc/dmsintc.c
>> @@ -0,0 +1,110 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (C) 2025 Loongson Technology Corporation Limited
>> + */
>> +
>> +#include <linux/kvm_host.h>
>> +#include <asm/kvm_dmsintc.h>
>> +#include <asm/kvm_vcpu.h>
>> +
>> +static int kvm_dmsintc_ctrl_access(struct kvm_device *dev,
>> +                struct kvm_device_attr *attr,
>> +                bool is_write)
>> +{
>> +    int addr = attr->attr;
>> +    void __user *data;
>> +    struct loongarch_dmsintc *s = dev->kvm->arch.dmsintc;
>> +    u64 tmp;
>> +
>> +    data = (void __user *)attr->addr;
>> +    switch (addr) {
>> +    case KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_BASE:
>> +        if (is_write) {
>> +            if (copy_from_user(&tmp, data, sizeof(s->msg_addr_base)))
>> +                return -EFAULT;
>> +            if (s->msg_addr_base) {
>> +                /* Duplicate setting are not allowed. */
>> +                return -EFAULT;
>> +            }
>> +            if ((tmp & (BIT(AVEC_CPU_SHIFT) - 1)) == 0)
>> +                s->msg_addr_base = tmp;
>> +            else
>> +                return  -EFAULT;
>> +        }
>> +        break;
>> +    case KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_SIZE:
>> +        if (is_write) {
>> +            if (copy_from_user(&tmp, data, sizeof(s->msg_addr_size)))
>> +                return -EFAULT;
>> +            if (s->msg_addr_size) {
>> +                /*Duplicate setting are not allowed. */
>> +                return -EFAULT;
>> +            }
>> +            s->msg_addr_size = tmp;
>> +        }
>> +        break;
>> +    default:
>> +        kvm_err("%s: unknown dmsintc register, addr = %d\n", 
>> __func__, addr);
>> +        return -ENXIO;
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>> +static int kvm_dmsintc_set_attr(struct kvm_device *dev,
>> +            struct kvm_device_attr *attr)
>> +{
>> +    switch (attr->group) {
>> +    case KVM_DEV_LOONGARCH_DMSINTC_CTRL:
>> +        return kvm_dmsintc_ctrl_access(dev, attr, true);
>> +    default:
>> +        kvm_err("%s: unknown group (%d)\n", __func__, attr->group);
>> +        return -EINVAL;
>> +    }
>> +}
>> +
>> +static int kvm_dmsintc_create(struct kvm_device *dev, u32 type)
>> +{
>> +    struct kvm *kvm;
>> +    struct loongarch_dmsintc *s;
>> +
>> +    if (!dev) {
>> +        kvm_err("%s: kvm_device ptr is invalid!\n", __func__);
>> +        return -EINVAL;
>> +    }
>> +
>> +    kvm = dev->kvm;
>> +    if (kvm->arch.dmsintc) {
>> +        kvm_err("%s: LoongArch DMSINTC has already been created!\n", 
>> __func__);
>> +        return -EINVAL;
>> +    }
>> +
>> +    s = kzalloc(sizeof(struct loongarch_dmsintc), GFP_KERNEL);
>> +    if (!s)
>> +        return -ENOMEM;
>> +
>> +    s->kvm = kvm;
>> +    kvm->arch.dmsintc = s;
>> +    return 0;
>> +}
>> +
>> +static void kvm_dmsintc_destroy(struct kvm_device *dev)
>> +{
>> +
>> +    if (!dev || !dev->kvm || !dev->kvm->arch.dmsintc)
>> +        return;
>> +
>> +    kfree(dev->kvm->arch.dmsintc);
>> +}
>> +
>> +static struct kvm_device_ops kvm_dmsintc_dev_ops = {
>> +    .name = "kvm-loongarch-dmsintc",
>> +    .create = kvm_dmsintc_create,
>> +    .destroy = kvm_dmsintc_destroy,
>> +    .set_attr = kvm_dmsintc_set_attr,
>> +};
>> +
>> +int kvm_loongarch_register_dmsintc_device(void)
>> +{
>> +    return kvm_register_device_ops(&kvm_dmsintc_dev_ops, 
>> KVM_DEV_TYPE_LOONGARCH_DMSINTC);
>> +}
>> diff --git a/arch/loongarch/kvm/main.c b/arch/loongarch/kvm/main.c
>> index 80ea63d465b8..2e26d4fd9000 100644
>> --- a/arch/loongarch/kvm/main.c
>> +++ b/arch/loongarch/kvm/main.c
>> @@ -408,6 +408,11 @@ static int kvm_loongarch_env_init(void)
>>         /* Register LoongArch PCH-PIC interrupt controller interface. */
>>       ret = kvm_loongarch_register_pch_pic_device();
>> +    if (ret)
>> +        return ret;
>> +
>> +    /* Register LoongArch DMSINTC interrupt contrroller interface */
>> +    ret = kvm_loongarch_register_dmsintc_device();
> I think it will be better if cpu_has_msgint() is added, in theory 
> dmsintc cannot be added on 3C5000 host machine, and KVM cannot prevent 
> VMM executing FUZZ ioctl commands.
>
I will add it on next version.

Thanks.
Song Gao
> Regards
> Bibo Mao
>>         return ret;
>>   }
>> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
>> index dddb781b0507..7c56e7e36265 100644
>> --- a/include/uapi/linux/kvm.h
>> +++ b/include/uapi/linux/kvm.h
>> @@ -1209,6 +1209,8 @@ enum kvm_device_type {
>>   #define KVM_DEV_TYPE_LOONGARCH_EIOINTC KVM_DEV_TYPE_LOONGARCH_EIOINTC
>>       KVM_DEV_TYPE_LOONGARCH_PCHPIC,
>>   #define KVM_DEV_TYPE_LOONGARCH_PCHPIC KVM_DEV_TYPE_LOONGARCH_PCHPIC
>> +    KVM_DEV_TYPE_LOONGARCH_DMSINTC,
>> +#define KVM_DEV_TYPE_LOONGARCH_DMSINTC KVM_DEV_TYPE_LOONGARCH_DMSINTC
>>         KVM_DEV_TYPE_MAX,
>>
Re: [PATCH v4 1/3] LongArch: KVM: Add DMSINTC device support
Posted by WANG Xuerui 1 month, 3 weeks ago 
On 12/18/25 19:18, Song Gao wrote:
> Add device model for DMSINTC interrupt controller, implement basic
> create/destroy/set_attr interfaces, and register device model to kvm
> device table.
> 
> Reviewed-by: Bibo Mao <maobibo@loongson.cn>
> Signed-off-by: Song Gao <gaosong@loongson.cn>
> ---
>   arch/loongarch/include/asm/kvm_dmsintc.h |  21 +++++
>   arch/loongarch/include/asm/kvm_host.h    |   3 +
>   arch/loongarch/include/uapi/asm/kvm.h    |   4 +
>   arch/loongarch/kvm/Makefile              |   1 +
>   arch/loongarch/kvm/intc/dmsintc.c        | 110 +++++++++++++++++++++++
>   arch/loongarch/kvm/main.c                |   5 ++
>   include/uapi/linux/kvm.h                 |   2 +
>   7 files changed, 146 insertions(+)
>   create mode 100644 arch/loongarch/include/asm/kvm_dmsintc.h
>   create mode 100644 arch/loongarch/kvm/intc/dmsintc.c
> 
> diff --git a/arch/loongarch/include/asm/kvm_dmsintc.h b/arch/loongarch/include/asm/kvm_dmsintc.h
> new file mode 100644
> index 000000000000..1d4f66996f3c
> --- /dev/null
> +++ b/arch/loongarch/include/asm/kvm_dmsintc.h
> @@ -0,0 +1,21 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2025 Loongson Technology Corporation Limited
> + */
> +
> +#ifndef __ASM_KVM_DMSINTC_H
> +#define __ASM_KVM_DMSINTC_H
> +
> +
> +struct loongarch_dmsintc  {
> +	struct kvm *kvm;
> +	uint64_t msg_addr_base;
> +	uint64_t msg_addr_size;
> +};
> +
> +struct dmsintc_state {
> +	atomic64_t  vector_map[4];
> +};
> +
> +int kvm_loongarch_register_dmsintc_device(void);
> +#endif
> diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h
> index e4fe5b8e8149..5e9e2af7312f 100644
> --- a/arch/loongarch/include/asm/kvm_host.h
> +++ b/arch/loongarch/include/asm/kvm_host.h
> @@ -22,6 +22,7 @@
>   #include <asm/kvm_ipi.h>
>   #include <asm/kvm_eiointc.h>
>   #include <asm/kvm_pch_pic.h>
> +#include <asm/kvm_dmsintc.h>
>   #include <asm/loongarch.h>
>   
>   #define __KVM_HAVE_ARCH_INTC_INITIALIZED
> @@ -134,6 +135,7 @@ struct kvm_arch {
>   	struct loongarch_ipi *ipi;
>   	struct loongarch_eiointc *eiointc;
>   	struct loongarch_pch_pic *pch_pic;
> +	struct loongarch_dmsintc *dmsintc;
>   };
>   
>   #define CSR_MAX_NUMS		0x800
> @@ -244,6 +246,7 @@ struct kvm_vcpu_arch {
>   	struct kvm_mp_state mp_state;
>   	/* ipi state */
>   	struct ipi_state ipi_state;
> +	struct dmsintc_state dmsintc_state;
>   	/* cpucfg */
>   	u32 cpucfg[KVM_MAX_CPUCFG_REGS];
>   
> diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h
> index de6c3f18e40a..0a370d018b08 100644
> --- a/arch/loongarch/include/uapi/asm/kvm.h
> +++ b/arch/loongarch/include/uapi/asm/kvm.h
> @@ -154,4 +154,8 @@ struct kvm_iocsr_entry {
>   #define KVM_DEV_LOONGARCH_PCH_PIC_GRP_CTRL	        0x40000006
>   #define KVM_DEV_LOONGARCH_PCH_PIC_CTRL_INIT	        0
>   
> +#define KVM_DEV_LOONGARCH_DMSINTC_CTRL			0x40000007
> +#define KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_BASE		0x0
> +#define KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_SIZE		0x1
> +
>   #endif /* __UAPI_ASM_LOONGARCH_KVM_H */
> diff --git a/arch/loongarch/kvm/Makefile b/arch/loongarch/kvm/Makefile
> index cb41d9265662..6e184e24443c 100644
> --- a/arch/loongarch/kvm/Makefile
> +++ b/arch/loongarch/kvm/Makefile
> @@ -19,6 +19,7 @@ kvm-y += vm.o
>   kvm-y += intc/ipi.o
>   kvm-y += intc/eiointc.o
>   kvm-y += intc/pch_pic.o
> +kvm-y += intc/dmsintc.o
>   kvm-y += irqfd.o
>   
>   CFLAGS_exit.o	+= $(call cc-disable-warning, override-init)
> diff --git a/arch/loongarch/kvm/intc/dmsintc.c b/arch/loongarch/kvm/intc/dmsintc.c
> new file mode 100644
> index 000000000000..3fdea81a08c8
> --- /dev/null
> +++ b/arch/loongarch/kvm/intc/dmsintc.c
> @@ -0,0 +1,110 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2025 Loongson Technology Corporation Limited
> + */
> +
> +#include <linux/kvm_host.h>
> +#include <asm/kvm_dmsintc.h>
> +#include <asm/kvm_vcpu.h>
> +
> +static int kvm_dmsintc_ctrl_access(struct kvm_device *dev,
> +				struct kvm_device_attr *attr,
> +				bool is_write)
> +{
> +	int addr = attr->attr;
> +	void __user *data;
> +	struct loongarch_dmsintc *s = dev->kvm->arch.dmsintc;
> +	u64 tmp;
> +
> +	data = (void __user *)attr->addr;
> +	switch (addr) {
> +	case KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_BASE:
> +		if (is_write) {
> +			if (copy_from_user(&tmp, data, sizeof(s->msg_addr_base)))
> +				return -EFAULT;
> +			if (s->msg_addr_base) {
> +				/* Duplicate setting are not allowed. */
> +				return -EFAULT;
> +			}
> +			if ((tmp & (BIT(AVEC_CPU_SHIFT) - 1)) == 0)
> +				s->msg_addr_base = tmp;
> +			else
> +				return  -EFAULT;
> +		}
> +		break;
> +	case KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_SIZE:
> +		if (is_write) {
> +			if (copy_from_user(&tmp, data, sizeof(s->msg_addr_size)))
> +				return -EFAULT;
> +			if (s->msg_addr_size) {
> +				/*Duplicate setting are not allowed. */
> +				return -EFAULT;
> +			}
> +			s->msg_addr_size = tmp;
> +		}
> +		break;
> +	default:
> +		kvm_err("%s: unknown dmsintc register, addr = %d\n", __func__, addr);
> +		return -ENXIO;
> +	}
> +
> +	return 0;
> +}
> +
> +static int kvm_dmsintc_set_attr(struct kvm_device *dev,
> +			struct kvm_device_attr *attr)
> +{
> +	switch (attr->group) {
> +	case KVM_DEV_LOONGARCH_DMSINTC_CTRL:
> +		return kvm_dmsintc_ctrl_access(dev, attr, true);
> +	default:
> +		kvm_err("%s: unknown group (%d)\n", __func__, attr->group);
> +		return -EINVAL;
> +	}
> +}
> +
> +static int kvm_dmsintc_create(struct kvm_device *dev, u32 type)
> +{
> +	struct kvm *kvm;
> +	struct loongarch_dmsintc *s;
> +
> +	if (!dev) {
> +		kvm_err("%s: kvm_device ptr is invalid!\n", __func__);
> +		return -EINVAL;
> +	}
> +
> +	kvm = dev->kvm;
> +	if (kvm->arch.dmsintc) {
> +		kvm_err("%s: LoongArch DMSINTC has already been created!\n", __func__);
> +		return -EINVAL;
> +	}
> +
> +	s = kzalloc(sizeof(struct loongarch_dmsintc), GFP_KERNEL);
> +	if (!s)
> +		return -ENOMEM;
> +
> +	s->kvm = kvm;
> +	kvm->arch.dmsintc = s;
> +	return 0;
> +}
> +
> +static void kvm_dmsintc_destroy(struct kvm_device *dev)
> +{
> +
> +	if (!dev || !dev->kvm || !dev->kvm->arch.dmsintc)
> +		return;
> +
> +	kfree(dev->kvm->arch.dmsintc);
> +}
> +
> +static struct kvm_device_ops kvm_dmsintc_dev_ops = {
> +	.name = "kvm-loongarch-dmsintc",
> +	.create = kvm_dmsintc_create,
> +	.destroy = kvm_dmsintc_destroy,
> +	.set_attr = kvm_dmsintc_set_attr,
> +};
> +
> +int kvm_loongarch_register_dmsintc_device(void)
> +{
> +	return kvm_register_device_ops(&kvm_dmsintc_dev_ops, KVM_DEV_TYPE_LOONGARCH_DMSINTC);
> +}
> diff --git a/arch/loongarch/kvm/main.c b/arch/loongarch/kvm/main.c
> index 80ea63d465b8..2e26d4fd9000 100644
> --- a/arch/loongarch/kvm/main.c
> +++ b/arch/loongarch/kvm/main.c
> @@ -408,6 +408,11 @@ static int kvm_loongarch_env_init(void)
>   
>   	/* Register LoongArch PCH-PIC interrupt controller interface. */
>   	ret = kvm_loongarch_register_pch_pic_device();
> +	if (ret)
> +		return ret;
> +
> +	/* Register LoongArch DMSINTC interrupt contrroller interface */
> +	ret = kvm_loongarch_register_dmsintc_device();
>   
>   	return ret;
>   }
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index dddb781b0507..7c56e7e36265 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -1209,6 +1209,8 @@ enum kvm_device_type {
>   #define KVM_DEV_TYPE_LOONGARCH_EIOINTC	KVM_DEV_TYPE_LOONGARCH_EIOINTC
>   	KVM_DEV_TYPE_LOONGARCH_PCHPIC,
>   #define KVM_DEV_TYPE_LOONGARCH_PCHPIC	KVM_DEV_TYPE_LOONGARCH_PCHPIC
> +	KVM_DEV_TYPE_LOONGARCH_DMSINTC,
> +#define KVM_DEV_TYPE_LOONGARCH_DMSINTC   KVM_DEV_TYPE_LOONGARCH_DMSINTC
>   
>   	KVM_DEV_TYPE_MAX,
>   

Not a single line explaining what "DMSINTC" is? I checked v1, v2, and 
v3, no documentation regarding DINTC or DMSINTC at all. We can see (and 
Huacai explained in v3 review comment) "MSINTC" means "message-signaled 
interrupt controller", but what does "D" mean? You may want to update 
Documentation/arch/loongarch/irq-chip-model.rst for that.

-- 
Regards,
WANG "xen0n" Xuerui

Linux/LoongArch mailing list: https://lore.kernel.org/loongarch/
Re: [PATCH v4 1/3] LongArch: KVM: Add DMSINTC device support
Posted by Huacai Chen 1 month, 3 weeks ago 
On Fri, Dec 19, 2025 at 11:20 AM WANG Xuerui <kernel@xen0n.name> wrote:
>
> On 12/18/25 19:18, Song Gao wrote:
> > Add device model for DMSINTC interrupt controller, implement basic
> > create/destroy/set_attr interfaces, and register device model to kvm
> > device table.
> >
> > Reviewed-by: Bibo Mao <maobibo@loongson.cn>
> > Signed-off-by: Song Gao <gaosong@loongson.cn>
> > ---
> >   arch/loongarch/include/asm/kvm_dmsintc.h |  21 +++++
> >   arch/loongarch/include/asm/kvm_host.h    |   3 +
> >   arch/loongarch/include/uapi/asm/kvm.h    |   4 +
> >   arch/loongarch/kvm/Makefile              |   1 +
> >   arch/loongarch/kvm/intc/dmsintc.c        | 110 +++++++++++++++++++++++
> >   arch/loongarch/kvm/main.c                |   5 ++
> >   include/uapi/linux/kvm.h                 |   2 +
> >   7 files changed, 146 insertions(+)
> >   create mode 100644 arch/loongarch/include/asm/kvm_dmsintc.h
> >   create mode 100644 arch/loongarch/kvm/intc/dmsintc.c
> >
> > diff --git a/arch/loongarch/include/asm/kvm_dmsintc.h b/arch/loongarch/include/asm/kvm_dmsintc.h
> > new file mode 100644
> > index 000000000000..1d4f66996f3c
> > --- /dev/null
> > +++ b/arch/loongarch/include/asm/kvm_dmsintc.h
> > @@ -0,0 +1,21 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * Copyright (C) 2025 Loongson Technology Corporation Limited
> > + */
> > +
> > +#ifndef __ASM_KVM_DMSINTC_H
> > +#define __ASM_KVM_DMSINTC_H
> > +
> > +
> > +struct loongarch_dmsintc  {
> > +     struct kvm *kvm;
> > +     uint64_t msg_addr_base;
> > +     uint64_t msg_addr_size;
> > +};
> > +
> > +struct dmsintc_state {
> > +     atomic64_t  vector_map[4];
> > +};
> > +
> > +int kvm_loongarch_register_dmsintc_device(void);
> > +#endif
> > diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h
> > index e4fe5b8e8149..5e9e2af7312f 100644
> > --- a/arch/loongarch/include/asm/kvm_host.h
> > +++ b/arch/loongarch/include/asm/kvm_host.h
> > @@ -22,6 +22,7 @@
> >   #include <asm/kvm_ipi.h>
> >   #include <asm/kvm_eiointc.h>
> >   #include <asm/kvm_pch_pic.h>
> > +#include <asm/kvm_dmsintc.h>
> >   #include <asm/loongarch.h>
> >
> >   #define __KVM_HAVE_ARCH_INTC_INITIALIZED
> > @@ -134,6 +135,7 @@ struct kvm_arch {
> >       struct loongarch_ipi *ipi;
> >       struct loongarch_eiointc *eiointc;
> >       struct loongarch_pch_pic *pch_pic;
> > +     struct loongarch_dmsintc *dmsintc;
> >   };
> >
> >   #define CSR_MAX_NUMS                0x800
> > @@ -244,6 +246,7 @@ struct kvm_vcpu_arch {
> >       struct kvm_mp_state mp_state;
> >       /* ipi state */
> >       struct ipi_state ipi_state;
> > +     struct dmsintc_state dmsintc_state;
> >       /* cpucfg */
> >       u32 cpucfg[KVM_MAX_CPUCFG_REGS];
> >
> > diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h
> > index de6c3f18e40a..0a370d018b08 100644
> > --- a/arch/loongarch/include/uapi/asm/kvm.h
> > +++ b/arch/loongarch/include/uapi/asm/kvm.h
> > @@ -154,4 +154,8 @@ struct kvm_iocsr_entry {
> >   #define KVM_DEV_LOONGARCH_PCH_PIC_GRP_CTRL          0x40000006
> >   #define KVM_DEV_LOONGARCH_PCH_PIC_CTRL_INIT         0
> >
> > +#define KVM_DEV_LOONGARCH_DMSINTC_CTRL                       0x40000007
> > +#define KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_BASE              0x0
> > +#define KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_SIZE              0x1
> > +
> >   #endif /* __UAPI_ASM_LOONGARCH_KVM_H */
> > diff --git a/arch/loongarch/kvm/Makefile b/arch/loongarch/kvm/Makefile
> > index cb41d9265662..6e184e24443c 100644
> > --- a/arch/loongarch/kvm/Makefile
> > +++ b/arch/loongarch/kvm/Makefile
> > @@ -19,6 +19,7 @@ kvm-y += vm.o
> >   kvm-y += intc/ipi.o
> >   kvm-y += intc/eiointc.o
> >   kvm-y += intc/pch_pic.o
> > +kvm-y += intc/dmsintc.o
> >   kvm-y += irqfd.o
> >
> >   CFLAGS_exit.o       += $(call cc-disable-warning, override-init)
> > diff --git a/arch/loongarch/kvm/intc/dmsintc.c b/arch/loongarch/kvm/intc/dmsintc.c
> > new file mode 100644
> > index 000000000000..3fdea81a08c8
> > --- /dev/null
> > +++ b/arch/loongarch/kvm/intc/dmsintc.c
> > @@ -0,0 +1,110 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright (C) 2025 Loongson Technology Corporation Limited
> > + */
> > +
> > +#include <linux/kvm_host.h>
> > +#include <asm/kvm_dmsintc.h>
> > +#include <asm/kvm_vcpu.h>
> > +
> > +static int kvm_dmsintc_ctrl_access(struct kvm_device *dev,
> > +                             struct kvm_device_attr *attr,
> > +                             bool is_write)
> > +{
> > +     int addr = attr->attr;
> > +     void __user *data;
> > +     struct loongarch_dmsintc *s = dev->kvm->arch.dmsintc;
> > +     u64 tmp;
> > +
> > +     data = (void __user *)attr->addr;
> > +     switch (addr) {
> > +     case KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_BASE:
> > +             if (is_write) {
> > +                     if (copy_from_user(&tmp, data, sizeof(s->msg_addr_base)))
> > +                             return -EFAULT;
> > +                     if (s->msg_addr_base) {
> > +                             /* Duplicate setting are not allowed. */
> > +                             return -EFAULT;
> > +                     }
> > +                     if ((tmp & (BIT(AVEC_CPU_SHIFT) - 1)) == 0)
> > +                             s->msg_addr_base = tmp;
> > +                     else
> > +                             return  -EFAULT;
> > +             }
> > +             break;
> > +     case KVM_DEV_LOONGARCH_DMSINTC_MSG_ADDR_SIZE:
> > +             if (is_write) {
> > +                     if (copy_from_user(&tmp, data, sizeof(s->msg_addr_size)))
> > +                             return -EFAULT;
> > +                     if (s->msg_addr_size) {
> > +                             /*Duplicate setting are not allowed. */
> > +                             return -EFAULT;
> > +                     }
> > +                     s->msg_addr_size = tmp;
> > +             }
> > +             break;
> > +     default:
> > +             kvm_err("%s: unknown dmsintc register, addr = %d\n", __func__, addr);
> > +             return -ENXIO;
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int kvm_dmsintc_set_attr(struct kvm_device *dev,
> > +                     struct kvm_device_attr *attr)
> > +{
> > +     switch (attr->group) {
> > +     case KVM_DEV_LOONGARCH_DMSINTC_CTRL:
> > +             return kvm_dmsintc_ctrl_access(dev, attr, true);
> > +     default:
> > +             kvm_err("%s: unknown group (%d)\n", __func__, attr->group);
> > +             return -EINVAL;
> > +     }
> > +}
> > +
> > +static int kvm_dmsintc_create(struct kvm_device *dev, u32 type)
> > +{
> > +     struct kvm *kvm;
> > +     struct loongarch_dmsintc *s;
> > +
> > +     if (!dev) {
> > +             kvm_err("%s: kvm_device ptr is invalid!\n", __func__);
> > +             return -EINVAL;
> > +     }
> > +
> > +     kvm = dev->kvm;
> > +     if (kvm->arch.dmsintc) {
> > +             kvm_err("%s: LoongArch DMSINTC has already been created!\n", __func__);
> > +             return -EINVAL;
> > +     }
> > +
> > +     s = kzalloc(sizeof(struct loongarch_dmsintc), GFP_KERNEL);
> > +     if (!s)
> > +             return -ENOMEM;
> > +
> > +     s->kvm = kvm;
> > +     kvm->arch.dmsintc = s;
> > +     return 0;
> > +}
> > +
> > +static void kvm_dmsintc_destroy(struct kvm_device *dev)
> > +{
> > +
> > +     if (!dev || !dev->kvm || !dev->kvm->arch.dmsintc)
> > +             return;
> > +
> > +     kfree(dev->kvm->arch.dmsintc);
> > +}
> > +
> > +static struct kvm_device_ops kvm_dmsintc_dev_ops = {
> > +     .name = "kvm-loongarch-dmsintc",
> > +     .create = kvm_dmsintc_create,
> > +     .destroy = kvm_dmsintc_destroy,
> > +     .set_attr = kvm_dmsintc_set_attr,
> > +};
> > +
> > +int kvm_loongarch_register_dmsintc_device(void)
> > +{
> > +     return kvm_register_device_ops(&kvm_dmsintc_dev_ops, KVM_DEV_TYPE_LOONGARCH_DMSINTC);
> > +}
> > diff --git a/arch/loongarch/kvm/main.c b/arch/loongarch/kvm/main.c
> > index 80ea63d465b8..2e26d4fd9000 100644
> > --- a/arch/loongarch/kvm/main.c
> > +++ b/arch/loongarch/kvm/main.c
> > @@ -408,6 +408,11 @@ static int kvm_loongarch_env_init(void)
> >
> >       /* Register LoongArch PCH-PIC interrupt controller interface. */
> >       ret = kvm_loongarch_register_pch_pic_device();
> > +     if (ret)
> > +             return ret;
> > +
> > +     /* Register LoongArch DMSINTC interrupt contrroller interface */
> > +     ret = kvm_loongarch_register_dmsintc_device();
> >
> >       return ret;
> >   }
> > diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> > index dddb781b0507..7c56e7e36265 100644
> > --- a/include/uapi/linux/kvm.h
> > +++ b/include/uapi/linux/kvm.h
> > @@ -1209,6 +1209,8 @@ enum kvm_device_type {
> >   #define KVM_DEV_TYPE_LOONGARCH_EIOINTC      KVM_DEV_TYPE_LOONGARCH_EIOINTC
> >       KVM_DEV_TYPE_LOONGARCH_PCHPIC,
> >   #define KVM_DEV_TYPE_LOONGARCH_PCHPIC       KVM_DEV_TYPE_LOONGARCH_PCHPIC
> > +     KVM_DEV_TYPE_LOONGARCH_DMSINTC,
> > +#define KVM_DEV_TYPE_LOONGARCH_DMSINTC   KVM_DEV_TYPE_LOONGARCH_DMSINTC
> >
> >       KVM_DEV_TYPE_MAX,
> >
>
> Not a single line explaining what "DMSINTC" is? I checked v1, v2, and
> v3, no documentation regarding DINTC or DMSINTC at all. We can see (and
> Huacai explained in v3 review comment) "MSINTC" means "message-signaled
> interrupt controller", but what does "D" mean? You may want to update
> Documentation/arch/loongarch/irq-chip-model.rst for that.
D means Direct, from the Loongson-3C6000 user manual.

Huacai

>
> --
> Regards,
> WANG "xen0n" Xuerui
>
> Linux/LoongArch mailing list: https://lore.kernel.org/loongarch/

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