2018-03-14 17:27:46

by Sonny Rao

Subject: [PATCH] vhost: add vsock compat ioctl

This will allow usage of vsock from 32-bit binaries on a 64-bit
kernel.

Signed-off-by: Sonny Rao <[email protected]>
---
drivers/vhost/vsock.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
index 0d14e2ff19f16..d0e65e92110e5 100644
--- a/drivers/vhost/vsock.c
+++ b/drivers/vhost/vsock.c
@@ -705,6 +705,7 @@ static const struct file_operations vhost_vsock_fops = {
.release = vhost_vsock_dev_release,
.llseek = noop_llseek,
.unlocked_ioctl = vhost_vsock_dev_ioctl,
+ .compat_ioctl = vhost_vsock_dev_ioctl,
};

static struct miscdevice vhost_vsock_misc = {
--
2.13.5

2018-03-14 19:07:10

by Michael S. Tsirkin

Subject: Re: [PATCH] vhost: add vsock compat ioctl

On Wed, Mar 14, 2018 at 10:26:05AM -0700, Sonny Rao wrote:
> This will allow usage of vsock from 32-bit binaries on a 64-bit
> kernel.
>
> Signed-off-by: Sonny Rao <[email protected]>

I think you need to convert the pointer argument though.
Something along the lines of:

#ifdef CONFIG_COMPAT
static long vhost_vsock_dev_compat_ioctl(struct file *f, unsigned int ioctl,
unsigned long arg)
{
return vhost_vsock_dev_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
}
#endif



> ---
> drivers/vhost/vsock.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
> index 0d14e2ff19f16..d0e65e92110e5 100644
> --- a/drivers/vhost/vsock.c
> +++ b/drivers/vhost/vsock.c
> @@ -705,6 +705,7 @@ static const struct file_operations vhost_vsock_fops = {
> .release = vhost_vsock_dev_release,
> .llseek = noop_llseek,
> .unlocked_ioctl = vhost_vsock_dev_ioctl,
> + .compat_ioctl = vhost_vsock_dev_ioctl,
> };
>
> static struct miscdevice vhost_vsock_misc = {
> --
> 2.13.5

2018-03-14 20:41:34

by Sonny Rao

Subject: Re: [PATCH] vhost: add vsock compat ioctl

On Wed, Mar 14, 2018 at 12:05 PM, Michael S. Tsirkin <[email protected]> wrote:
> On Wed, Mar 14, 2018 at 10:26:05AM -0700, Sonny Rao wrote:
>> This will allow usage of vsock from 32-bit binaries on a 64-bit
>> kernel.
>>
>> Signed-off-by: Sonny Rao <[email protected]>
>
> I think you need to convert the pointer argument though.
> Something along the lines of:
>
> #ifdef CONFIG_COMPAT
> static long vhost_vsock_dev_compat_ioctl(struct file *f, unsigned int ioctl,
> unsigned long arg)
> {
> return vhost_vsock_dev_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
> }
> #endif

Ok, thanks for pointing that out -- it has worked for me so far, but
I'll re-spin as you suggested.

>
>
>
>> ---
>> drivers/vhost/vsock.c | 1 +
>> 1 file changed, 1 insertion(+)
>>
>> diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
>> index 0d14e2ff19f16..d0e65e92110e5 100644
>> --- a/drivers/vhost/vsock.c
>> +++ b/drivers/vhost/vsock.c
>> @@ -705,6 +705,7 @@ static const struct file_operations vhost_vsock_fops = {
>> .release = vhost_vsock_dev_release,
>> .llseek = noop_llseek,
>> .unlocked_ioctl = vhost_vsock_dev_ioctl,
>> + .compat_ioctl = vhost_vsock_dev_ioctl,
>> };
>>
>> static struct miscdevice vhost_vsock_misc = {
>> --
>> 2.13.5