driver/svm: used tgid when get phys

ascend inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I4EUVI


CVE: NA

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The user needs the process pid, that is, task tgid.

Signed-off-by: Zhou Guanghui <zhouguanghui1@huawei.com>
Reviewed-by: Weilong Chen <chenweilong@huawei.com>
Reviewed-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>

drivers/char/svm.c

@@ -348,7 +348,7 @@ static void svm_set_slot_valid(unsigned long index, unsigned long phys)
 
 	*((unsigned long *)slot->data) = phys;
 	slot->image_word = SVM_IMAGE_WORD_VALID;
-	slot->pid = current->pid;
+	slot->pid = current->tgid;
 	slot->data_type = SVM_VA2PA_TYPE_DMA;
 	__bitmap_set(va2pa_trunk.bitmap, index, 1);
 	va2pa_trunk.slot_used++;