[PATCH v5 1/1] virt: acrn: Mark the uuid field as unused

From: Andy Shevchenko
Date: Wed Nov 16 2022 - 11:37:20 EST


After the commits for userspace (see Link tags below) the uuid field
is not being used in the ACRN code. Update kernel to reflect these
changes, i.e. do the following:
- adding a comment explaining that it's not used anymore
- replacing the specific type by a raw buffer
- updating the example code accordingly

The advertised field confused users and actually never been used.
So the wrong part here is that kernel puts something which userspace
never used and hence this may confuse a reader of this code.

Note, that there is only a single tool that had been prepared a year
ago for these forthcoming changes in the kernel.

Link: https://github.com/projectacrn/acrn-hypervisor/commit/da0d24326ed6
Link: https://github.com/projectacrn/acrn-hypervisor/commit/bb0327e70097
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Acked-by: Rafael J. Wysocki <rafael@xxxxxxxxxx>
---
v5: removed Fixes tags (Greg), updated field description (Greg),
update commit message to show that no tool will be broken (Greg)
v4: added tag (Rafael), Cc'ed to Greg (missing in the previous version
by some reason)
v3: converted to Link tags (Rafael), explained what was wrong (Rafael)
v2: added tag (Fei)

include/uapi/linux/acrn.h | 5 ++---
samples/acrn/vm-sample.c | 3 ---
2 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/include/uapi/linux/acrn.h b/include/uapi/linux/acrn.h
index ccf47ed92500..7b714c1902eb 100644
--- a/include/uapi/linux/acrn.h
+++ b/include/uapi/linux/acrn.h
@@ -12,7 +12,6 @@
#define _UAPI_ACRN_H

#include <linux/types.h>
-#include <linux/uuid.h>

#define ACRN_IO_REQUEST_MAX 16

@@ -186,7 +185,7 @@ struct acrn_ioreq_notify {
* @reserved0: Reserved and must be 0
* @vcpu_num: Number of vCPU in the VM. Return from hypervisor.
* @reserved1: Reserved and must be 0
- * @uuid: UUID of the VM. Pass to hypervisor directly.
+ * @uuid: Empty space never to be used again (used to be UUID of the VM)
* @vm_flag: Flag of the VM creating. Pass to hypervisor directly.
* @ioreq_buf: Service VM GPA of I/O request buffer. Pass to
* hypervisor directly.
@@ -198,7 +197,7 @@ struct acrn_vm_creation {
__u16 reserved0;
__u16 vcpu_num;
__u16 reserved1;
- guid_t uuid;
+ __u8 uuid[16];
__u64 vm_flag;
__u64 ioreq_buf;
__u64 cpu_affinity;
diff --git a/samples/acrn/vm-sample.c b/samples/acrn/vm-sample.c
index b2dad47a77a0..7abd68b20153 100644
--- a/samples/acrn/vm-sample.c
+++ b/samples/acrn/vm-sample.c
@@ -29,8 +29,6 @@ static struct acrn_io_request *io_req_buf = (struct acrn_io_request *)io_request

__u16 vcpu_num;
__u16 vmid;
-/* POST_STANDARD_VM_UUID1, refer to https://github.com/projectacrn/acrn-hypervisor/blob/master/hypervisor/include/common/vm_uuids.h */
-guid_t vm_uuid = GUID_INIT(0x385479d2, 0xd625, 0xe811, 0x86, 0x4e, 0xcb, 0x7a, 0x18, 0xb3, 0x46, 0x43);

int hsm_fd;
int is_running = 1;
@@ -63,7 +61,6 @@ int main(int argc, char **argv)
}
hsm_fd = open("/dev/acrn_hsm", O_RDWR|O_CLOEXEC);

- memcpy(&create_vm.uuid, &vm_uuid, 16);
create_vm.ioreq_buf = (__u64)io_req_buf;
ret = ioctl(hsm_fd, ACRN_IOCTL_CREATE_VM, &create_vm);
printf("Created VM! [%d]\n", ret);
--
2.35.1