Linux Virtualization - Sep 2018 - [PATCH] vhost: fix VHOST_GET_BACKEND_FEATURES ioctl request definition

On 2018?09?04? 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 at
altlinux.org>
> 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 at redhat.com>
>
>> ---
>>   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

On Tue, Sep 04, 2018 at 11:08:40AM +0800, Jason Wang
wrote:
> 
> 
> On 2018?09?04? 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 at
altlinux.org>
> > 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 at redhat.com>

OK then

Acked-by: Michael S. Tsirkin <mst at redhat.com>
> > 
> > > ---
> > >   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

From: "Michael S. Tsirkin" <mst at redhat.com>
Date: Mon, 3 Sep 2018 23:11:11 -0400
> On Tue, Sep 04, 2018 at 11:08:40AM +0800, Jason Wang wrote:
>> 
>> 
>> On 2018?09?04? 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 at
altlinux.org>
>> > 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 at redhat.com>
> 
> 
> OK then
> 
> Acked-by: Michael S. Tsirkin <mst at redhat.com>
Applied, thanks everyone.