s390: uv: Fix sysfs max number of VCPUs reporting

The number reported by the query is N-1 and I think people reading the sysfs file would expect N instead. For users creating VMs there's no actual difference because KVM's limit is currently below the UV's limit. Signed-off-by: Janosch Frank <[email protected]> Fixes: a0f60f8 ("s390/protvirt: Add sysfs firmware interface for Ultravisor information") Cc: [email protected] Reviewed-by: Claudio Imbrenda <[email protected]> Acked-by: Cornelia Huck <[email protected]> Signed-off-by: Vasily Gorbik <[email protected]>
kawasaki · Jan 27, 2021 · e82080e · e82080e
1 parent 6c12a63
commit e82080e
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Showing 3 changed files with 4 additions and 4 deletions.
diff --git a/arch/s390/boot/uv.c b/arch/s390/boot/uv.c
@@ -35,7 +35,7 @@ void uv_query_info(void)
 		uv_info.guest_cpu_stor_len = uvcb.cpu_stor_len;
 		uv_info.max_sec_stor_addr = ALIGN(uvcb.max_guest_stor_addr, PAGE_SIZE);
 		uv_info.max_num_sec_conf = uvcb.max_num_sec_conf;
-		uv_info.max_guest_cpus = uvcb.max_guest_cpus;
+		uv_info.max_guest_cpu_id = uvcb.max_guest_cpu_id;
 	}
 
 #ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST

diff --git a/arch/s390/include/asm/uv.h b/arch/s390/include/asm/uv.h
@@ -96,7 +96,7 @@ struct uv_cb_qui {
 	u32 max_num_sec_conf;
 	u64 max_guest_stor_addr;
 	u8  reserved88[158 - 136];
-	u16 max_guest_cpus;
+	u16 max_guest_cpu_id;
 	u8  reserveda0[200 - 160];
 } __packed __aligned(8);
 
@@ -273,7 +273,7 @@ struct uv_info {
 	unsigned long guest_cpu_stor_len;
 	unsigned long max_sec_stor_addr;
 	unsigned int max_num_sec_conf;
-	unsigned short max_guest_cpus;
+	unsigned short max_guest_cpu_id;
 };
 
 extern struct uv_info uv_info;

diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c
@@ -368,7 +368,7 @@ static ssize_t uv_query_max_guest_cpus(struct kobject *kobj,
 				       struct kobj_attribute *attr, char *page)
 {
 	return scnprintf(page, PAGE_SIZE, "%d\n",
-			uv_info.max_guest_cpus);
+			uv_info.max_guest_cpu_id + 1);
 }
 
 static struct kobj_attribute uv_query_max_guest_cpus_attr =