diff mbox series

[v2,3/7] vdpa: validate provisioned device features against specified attribute

Message ID 1675207345-22328-4-git-send-email-si-wei.liu@oracle.com
State New
Headers
Series features provisioning fixes and mlx5_vdpa support |

Commit Message

Si-Wei Liu Jan. 31, 2023, 11:22 p.m. UTC 
  With device feature provisioning, there's a chance for misconfiguration
that the vdpa feature attribute supplied in 'vdpa dev add' command doesn't
get selected on the device_features to be provisioned. For instance, when
a @mac attribute is specified, the corresponding feature bit _F_MAC in
device_features should be set for consistency. If there's conflict on
provisioned features against the attribute, it should be treated as an
error to fail the ambiguous command. Noted the opposite is not
necessarily true, for e.g. it's okay to have _F_MAC set in device_features
without providing a corresponding @mac attribute, in which case the vdpa
vendor driver could load certain default value for attribute that is not
explicitly specified.

Generalize this check in vdpa core so that there's no duplicate code in
each vendor driver.

Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
---
 drivers/vdpa/vdpa.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

Comments

Parav Pandit Feb. 2, 2023, 5:05 a.m. UTC | #1 
> From: Si-Wei Liu <si-wei.liu@oracle.com>
> Sent: Tuesday, January 31, 2023 6:22 PM
> 
> With device feature provisioning, there's a chance for misconfiguration that the
> vdpa feature attribute supplied in 'vdpa dev add' command doesn't get
> selected on the device_features to be provisioned. For instance, when a @mac
> attribute is specified, the corresponding feature bit _F_MAC in device_features
> should be set for consistency. If there's conflict on provisioned features against
> the attribute, it should be treated as an error to fail the ambiguous command.
> Noted the opposite is not necessarily true, for e.g. it's okay to have _F_MAC set
> in device_features without providing a corresponding @mac attribute, in which
> case the vdpa vendor driver could load certain default value for attribute that is
> not explicitly specified.
> 
> Generalize this check in vdpa core so that there's no duplicate code in each
> vendor driver.
> 
> Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
> ---
>  drivers/vdpa/vdpa.c | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c index 21c8aa3..1eba978
> 100644
> --- a/drivers/vdpa/vdpa.c
> +++ b/drivers/vdpa/vdpa.c
> @@ -601,8 +601,26 @@ static int vdpa_nl_cmd_dev_add_set_doit(struct
> sk_buff *skb, struct genl_info *i
>  		config.mask |=
> BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MAX_VQP);
>  	}
>  	if (nl_attrs[VDPA_ATTR_DEV_FEATURES]) {
> +		u64 missing = 0x0ULL;
> +
>  		config.device_features =
>  			nla_get_u64(nl_attrs[VDPA_ATTR_DEV_FEATURES]);
> +		if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MACADDR] &&
> +		    !(config.device_features & BIT_ULL(VIRTIO_NET_F_MAC)))
> +			missing |= BIT_ULL(VIRTIO_NET_F_MAC);
> +		if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MTU] &&
> +		    !(config.device_features & BIT_ULL(VIRTIO_NET_F_MTU)))
> +			missing |= BIT_ULL(VIRTIO_NET_F_MTU);
> +		if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MAX_VQP] &&
> +		    config.net.max_vq_pairs > 1 &&
> +		    !(config.device_features & BIT_ULL(VIRTIO_NET_F_MQ)))
> +			missing |= BIT_ULL(VIRTIO_NET_F_MQ);
> +		if (missing) {
> +			NL_SET_ERR_MSG_FMT_MOD(info->extack,
> +					       "Missing features 0x%llx for
> provided attributes",
> +					       missing);
> +			return -EINVAL;
> +		}
>  		config.mask |= BIT_ULL(VDPA_ATTR_DEV_FEATURES);
>  	}
> 
> --
> 1.8.3.1
Vdpa this layer can likely derive the feature bits for the supplied config fields so that user doesn't need to keep track of both.
Only those feature bits which are unrelated to any config, is what user should be setting.
Si-Wei Liu Feb. 2, 2023, 9:58 p.m. UTC | #2 
On 2/1/2023 9:05 PM, Parav Pandit wrote:
>
>> From: Si-Wei Liu <si-wei.liu@oracle.com>
>> Sent: Tuesday, January 31, 2023 6:22 PM
>>
>> With device feature provisioning, there's a chance for misconfiguration that the
>> vdpa feature attribute supplied in 'vdpa dev add' command doesn't get
>> selected on the device_features to be provisioned. For instance, when a @mac
>> attribute is specified, the corresponding feature bit _F_MAC in device_features
>> should be set for consistency. If there's conflict on provisioned features against
>> the attribute, it should be treated as an error to fail the ambiguous command.
>> Noted the opposite is not necessarily true, for e.g. it's okay to have _F_MAC set
>> in device_features without providing a corresponding @mac attribute, in which
>> case the vdpa vendor driver could load certain default value for attribute that is
>> not explicitly specified.
>>
>> Generalize this check in vdpa core so that there's no duplicate code in each
>> vendor driver.
>>
>> Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
>> ---
>>   drivers/vdpa/vdpa.c | 18 ++++++++++++++++++
>>   1 file changed, 18 insertions(+)
>>
>> diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c index 21c8aa3..1eba978
>> 100644
>> --- a/drivers/vdpa/vdpa.c
>> +++ b/drivers/vdpa/vdpa.c
>> @@ -601,8 +601,26 @@ static int vdpa_nl_cmd_dev_add_set_doit(struct
>> sk_buff *skb, struct genl_info *i
>>   		config.mask |=
>> BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MAX_VQP);
>>   	}
>>   	if (nl_attrs[VDPA_ATTR_DEV_FEATURES]) {
>> +		u64 missing = 0x0ULL;
>> +
>>   		config.device_features =
>>   			nla_get_u64(nl_attrs[VDPA_ATTR_DEV_FEATURES]);
>> +		if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MACADDR] &&
>> +		    !(config.device_features & BIT_ULL(VIRTIO_NET_F_MAC)))
>> +			missing |= BIT_ULL(VIRTIO_NET_F_MAC);
>> +		if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MTU] &&
>> +		    !(config.device_features & BIT_ULL(VIRTIO_NET_F_MTU)))
>> +			missing |= BIT_ULL(VIRTIO_NET_F_MTU);
>> +		if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MAX_VQP] &&
>> +		    config.net.max_vq_pairs > 1 &&
>> +		    !(config.device_features & BIT_ULL(VIRTIO_NET_F_MQ)))
>> +			missing |= BIT_ULL(VIRTIO_NET_F_MQ);
>> +		if (missing) {
>> +			NL_SET_ERR_MSG_FMT_MOD(info->extack,
>> +					       "Missing features 0x%llx for
>> provided attributes",
>> +					       missing);
>> +			return -EINVAL;
>> +		}
>>   		config.mask |= BIT_ULL(VDPA_ATTR_DEV_FEATURES);
>>   	}
>>
>> --
>> 1.8.3.1
> Vdpa this layer can likely derive the feature bits for the supplied config fields so that user doesn't need to keep track of both.
> Only those feature bits which are unrelated to any config, is what user should be setting.
It's not I can't do this, but Jason wanted to have clear semantics 
around migration compatibility for the driver, and for that users have 
to explicitly provide device_features that we may define new driver 
behavior (rather that inheritance which is implicit and not uniformly 
define across drivers) for compatibility using the new uAPI.

Thanks,
-Siwei
Parav Pandit Feb. 2, 2023, 10:01 p.m. UTC | #3 
> From: Si-Wei Liu <si-wei.liu@oracle.com>
> Sent: Thursday, February 2, 2023 4:59 PM
> 
> On 2/1/2023 9:05 PM, Parav Pandit wrote:
> >
> >> From: Si-Wei Liu <si-wei.liu@oracle.com>
> >> Sent: Tuesday, January 31, 2023 6:22 PM
> >>
> >> With device feature provisioning, there's a chance for
> >> misconfiguration that the vdpa feature attribute supplied in 'vdpa
> >> dev add' command doesn't get selected on the device_features to be
> >> provisioned. For instance, when a @mac attribute is specified, the
> >> corresponding feature bit _F_MAC in device_features should be set for
> >> consistency. If there's conflict on provisioned features against the attribute,
> it should be treated as an error to fail the ambiguous command.
> >> Noted the opposite is not necessarily true, for e.g. it's okay to
> >> have _F_MAC set in device_features without providing a corresponding
> >> @mac attribute, in which case the vdpa vendor driver could load
> >> certain default value for attribute that is not explicitly specified.
> >>
> >> Generalize this check in vdpa core so that there's no duplicate code
> >> in each vendor driver.
> >>
> >> Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
> >> ---
> >>   drivers/vdpa/vdpa.c | 18 ++++++++++++++++++
> >>   1 file changed, 18 insertions(+)
> >>
> >> diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c index
> >> 21c8aa3..1eba978
> >> 100644
> >> --- a/drivers/vdpa/vdpa.c
> >> +++ b/drivers/vdpa/vdpa.c
> >> @@ -601,8 +601,26 @@ static int vdpa_nl_cmd_dev_add_set_doit(struct
> >> sk_buff *skb, struct genl_info *i
> >>   		config.mask |=
> >> BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MAX_VQP);
> >>   	}
> >>   	if (nl_attrs[VDPA_ATTR_DEV_FEATURES]) {
> >> +		u64 missing = 0x0ULL;
> >> +
> >>   		config.device_features =
> >>   			nla_get_u64(nl_attrs[VDPA_ATTR_DEV_FEATURES]);
> >> +		if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MACADDR] &&
> >> +		    !(config.device_features & BIT_ULL(VIRTIO_NET_F_MAC)))
> >> +			missing |= BIT_ULL(VIRTIO_NET_F_MAC);
> >> +		if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MTU] &&
> >> +		    !(config.device_features & BIT_ULL(VIRTIO_NET_F_MTU)))
> >> +			missing |= BIT_ULL(VIRTIO_NET_F_MTU);
> >> +		if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MAX_VQP] &&
> >> +		    config.net.max_vq_pairs > 1 &&
> >> +		    !(config.device_features & BIT_ULL(VIRTIO_NET_F_MQ)))
> >> +			missing |= BIT_ULL(VIRTIO_NET_F_MQ);
> >> +		if (missing) {
> >> +			NL_SET_ERR_MSG_FMT_MOD(info->extack,
> >> +					       "Missing features 0x%llx for
> >> provided attributes",
> >> +					       missing);
> >> +			return -EINVAL;
> >> +		}
> >>   		config.mask |= BIT_ULL(VDPA_ATTR_DEV_FEATURES);
> >>   	}
> >>
> >> --
> >> 1.8.3.1
> > Vdpa this layer can likely derive the feature bits for the supplied config fields
> so that user doesn't need to keep track of both.
> > Only those feature bits which are unrelated to any config, is what user should
> be setting.
> It's not I can't do this, but Jason wanted to have clear semantics around
> migration compatibility for the driver, and for that users have to explicitly
> provide device_features that we may define new driver behavior (rather that
> inheritance which is implicit and not uniformly define across drivers) for
> compatibility using the new uAPI.
Make sense to explicitly tell, just requires more careful plumbing on the user space side.
Eventually it will get orchestrated by non user, so it should be fine to explicitly define it.
diff mbox series

Patch

diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
index 21c8aa3..1eba978 100644
--- a/drivers/vdpa/vdpa.c
+++ b/drivers/vdpa/vdpa.c
@@ -601,8 +601,26 @@  static int vdpa_nl_cmd_dev_add_set_doit(struct sk_buff *skb, struct genl_info *i
 		config.mask |= BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MAX_VQP);
 	}
 	if (nl_attrs[VDPA_ATTR_DEV_FEATURES]) {
+		u64 missing = 0x0ULL;
+
 		config.device_features =
 			nla_get_u64(nl_attrs[VDPA_ATTR_DEV_FEATURES]);
+		if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MACADDR] &&
+		    !(config.device_features & BIT_ULL(VIRTIO_NET_F_MAC)))
+			missing |= BIT_ULL(VIRTIO_NET_F_MAC);
+		if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MTU] &&
+		    !(config.device_features & BIT_ULL(VIRTIO_NET_F_MTU)))
+			missing |= BIT_ULL(VIRTIO_NET_F_MTU);
+		if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MAX_VQP] &&
+		    config.net.max_vq_pairs > 1 &&
+		    !(config.device_features & BIT_ULL(VIRTIO_NET_F_MQ)))
+			missing |= BIT_ULL(VIRTIO_NET_F_MQ);
+		if (missing) {
+			NL_SET_ERR_MSG_FMT_MOD(info->extack,
+					       "Missing features 0x%llx for provided attributes",
+					       missing);
+			return -EINVAL;
+		}
 		config.mask |= BIT_ULL(VDPA_ATTR_DEV_FEATURES);
 	}