Re: [PATCH] vhost: fix VHOST_GET_BACKEND_FEATURES ioctl request definition

From: Jason Wang
Date: Mon Sep 03 2018 - 23:08:53 EST




On 2018å09æ04æ 10:22, Michael S. Tsirkin wrote:
On Mon, Sep 03, 2018 at 08:59:13PM +0300, Gleb Fotengauer-Malinovskiy wrote:
The _IOC_READ flag fits this ioctl request more because this request
actually only writes to, but doesn't read from userspace.
See NOTEs in include/uapi/asm-generic/ioctl.h for more information.

Fixes: 429711aec282 ("vhost: switch to use new message format")
Signed-off-by: Gleb Fotengauer-Malinovskiy <glebfm@xxxxxxxxxxxx>
Hmm it does make sense, and it's not too late to fix this up.
Jason, what's your take on this? Was _IOW intentional?

My bad, not intentional. And I agree that fixing this is not too late.

So

Acked-by: Jason Wang <jasowang@xxxxxxxxxx>


---
include/uapi/linux/vhost.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h
index b1e22c40c4b6..84c3de89696a 100644
--- a/include/uapi/linux/vhost.h
+++ b/include/uapi/linux/vhost.h
@@ -176,7 +176,7 @@ struct vhost_memory {
#define VHOST_BACKEND_F_IOTLB_MSG_V2 0x1
#define VHOST_SET_BACKEND_FEATURES _IOW(VHOST_VIRTIO, 0x25, __u64)
-#define VHOST_GET_BACKEND_FEATURES _IOW(VHOST_VIRTIO, 0x26, __u64)
+#define VHOST_GET_BACKEND_FEATURES _IOR(VHOST_VIRTIO, 0x26, __u64)
/* VHOST_NET specific defines */

--
glebfm