在 2021/12/25 2:19, Leon Romanovsky 写道:

On Fri, Dec 24, 2021 at 03:12:35PM +0800, Cheng Xu wrote:

quoted

On 12/24/21 6:55 AM, Yanjun Zhu wrote:

quoted

在 2021/12/24 2:45, Leon Romanovsky 写道:

quoted

On Thu, Dec 23, 2021 at 11:46:03PM +0800, Yanjun Zhu wrote:

quoted

在 2021/12/21 10:48, Cheng Xu 写道:

quoted

Signed-off-by: Cheng Xu <chengyou@linux.alibaba.com>
---
    include/uapi/rdma/erdma-abi.h | 49
+++++++++++++++++++++++++++++++++++
    1 file changed, 49 insertions(+)
    create mode 100644 include/uapi/rdma/erdma-abi.h

diff --git a/include/uapi/rdma/erdma-abi.h

b/include/uapi/rdma/erdma-abi.h
new file mode 100644
index 000000000000..6bcba10c1e41

--- /dev/null
+++ b/include/uapi/rdma/erdma-abi.h

@@ -0,0 +1,49 @@
+/* SPDX-License-Identifier: ((GPL-2.0 WITH

Linux-syscall-note) OR Linux-OpenIB) */
+/*
+ * Copyright (c) 2020-2021, Alibaba Group.
+ */
+
+#ifndef __ERDMA_USER_H__
+#define __ERDMA_USER_H__
+
+#include <linux/types.h>
+
+#define ERDMA_ABI_VERSION       1

ERDMA_ABI_VERSION should be 2？

Why?

This field is for rdma-core and we don't have erdma provider in that
library yet. It always starts from 1 for new drivers.

Please check this link:
http://mail.spinics.net/lists/linux-rdma/msg63012.html

Jason mentioned in this link:

"
/*
   * For 64 bit machines ABI version 1 and 2 are the same. Otherwise 32
   * bit machines require ABI version 2 which guarentees the user and
   * kernel use the same ABI.
   */
"

Zhu Yanjun

Even though I do not understand the reason, but as mentioned above, I think
ERDMA_ABI_VERSION = 1 is fine, because ERDMA can only work in 64bit
machines.

Jason's comment came after we discovered that many of our API structures had
problematic layout and weren't aligned to 64bits. This caused to issues when
the 32bits software tried to use 64bit kernel.

Got it. Thanks

Zhu Yanjun

So we didn't have many choices but bump ABI versions for broken drivers
and RXE was one of them.

You are proposing new driver, it should start from 1.

Thanks