Received-SPF: pass (google.com: domain of linux-kernel+bounces-154203-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:40f1:3f00::1 as permitted sender) client-ip=2604:1380:40f1:3f00::1;
Message-ID: <a12ac71c-5621-4014-9b01-e74ce7429120@intel.com>
Date: Mon, 22 Apr 2024 16:41:11 -0700
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH net-next] octeontx2-pf: flower: check for unsupported
 control flags
To: =?UTF-8?Q?Asbj=C3=B8rn_Sloth_T=C3=B8nnesen?= <ast@fiberby.net>,
	<netdev@vger.kernel.org>
CC: <linux-kernel@vger.kernel.org>, "David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>, Jakub Kicinski <kuba@kernel.org>, "Paolo
 Abeni" <pabeni@redhat.com>, Sunil Goutham <sgoutham@marvell.com>, "Geetha
 sowjanya" <gakula@marvell.com>, Subbaraya Sundeep <sbhatta@marvell.com>,
	hariprasad <hkelam@marvell.com>, Suman Ghosh <sumang@marvell.com>
References: <20240422152735.175693-1-ast@fiberby.net>
Content-Language: en-US
From: Jacob Keller <jacob.e.keller@intel.com>
In-Reply-To: <20240422152735.175693-1-ast@fiberby.net>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 8bit
Precedence: bulk
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?NHV1L2ZYdHF6UjVxaDIrQ0tXbi8yWXByc3UxUTJoTW5LMGx6Z0QxM0t6QmhX?=
 =?utf-8?B?ZWczL1FRNUc0Y00rV2FIRHVKSENHeUtoNHp4ZnBUR3JFR1RnK0pjVlJjaWhu?=
 =?utf-8?B?S2YzTEVRU2pnSGhRZHlyZFYybXNZU21pRnJtL0NKeVl6TjJyaklBM0dPb0d2?=
 =?utf-8?B?SEtSWHB2WTJrWTBjSzJuWVRpQ1AyMmRXc1FYQ21NS2FqRTN3TnNxQTArODFV?=
 =?utf-8?B?YXg3L280L0RHbWE5K3BHemt1SWducEgybTA0bEdzdGVkYktxNnlTdENtV2dV?=
 =?utf-8?B?bDFXY2xKUHppNm9Eb0krdnppMVljZE92RUpNSkliZzFZWnMweHZtdXhrQWlz?=
 =?utf-8?B?YUR1UTkzMDBNUVNwcDhETU43b21zc0R2bVpXMVQ2SFRHZTJKYnVIM2ZRK0lx?=
 =?utf-8?B?ZlpoL1VyV2hSYjdzTkVrRE9QcXd3QnV1UXh3ZmExVUZoMGFSMjNWenVSUjI1?=
 =?utf-8?B?MUVQYStMRXlLc0ZnYjRCYzRML21EYmNLa1A1bUdrRzhBTGdvcEp0a253QWln?=
 =?utf-8?B?NTB1VWRnQTZ0Qkp4NVRnMFVTSW5QeEFBVDA1ZHJYMUJ3Ym5aQVBweG0zbW56?=
 =?utf-8?B?U2p3NWJzd3Vqb2JOYU4ySTVnWjFWU2xGVkgwV2FnR2pZdzZFd2FyenBFVkkz?=
 =?utf-8?B?aTJpVkY2VlU2eDlkbGV0c0NnNkZvYVVZMHdpK29hODFrejBOcDdWVVZudkNp?=
 =?utf-8?B?Ri9Zem9pSEo3Qm5BR1p2M3YvUkZUZXpJOVdsVE5FdVgxWlZjdkxtcmQyQ3Yy?=
 =?utf-8?B?NlUxamxPRnF0RE5qdTllSGlOQkdUeVpGdjNIZGplUUYvVlpzZ2MySHAzaEpN?=
 =?utf-8?B?RDBsNlY3N1kyZUtXVGttazhWeUtqRnlLdWNvMHlQd1A3SHhMQkgvQkdjVmxX?=
 =?utf-8?B?NXBFUGhidktNaysrOVpRQjVpamM0NDd6SENqMU1lWDdXbzJQay9HKy9xVGpi?=
 =?utf-8?B?Q3lMWnFWZWhDUVBRVW1BcHpmSEZWL3RZUFhaV2xkOFo2MjYvVFdobVBqZFRI?=
 =?utf-8?B?SlVFMVVKWnpmRkJVWVNNMGFGTFRxbTdSbGg2ek8wQU1Bdi9OVFpHRmpkM0JO?=
 =?utf-8?B?L2xWaEJyeFRoU3BJYkU2QXVEVDFlK1pWN01vLzk0V3cybXFzNmVzRFB1K3ZG?=
 =?utf-8?B?SXN5MzhNbkkycWp5Nm5BalRLSGE5UUsvdEtweE40Ty9ic0luUW5OZHhQUkUw?=
 =?utf-8?B?dS9JVkJCSFpCdG13UlBWQ0xYcTlzL1BYNW5GSG9RUVV6em5jUlJsQkFtdlNM?=
 =?utf-8?B?SG1JbWFhZnM4WEVNbjZBTFU2bHp6THc3ZzFXN2QxZ0lTeU1mMjNmODJkaVdv?=
 =?utf-8?B?SWFSeU1kNzZzTXNsZVlRZlhiOHkzdnlTaTlkc0JyV2QzOWNMeTJKNzcyaXRN?=
 =?utf-8?B?MTY3bEFGOXBrS2lWeUk2bTFFQU50RmRvcG9GTU1JK3hZVUduNHJxVzJGeWFw?=
 =?utf-8?B?elJXS25QRnc3RVRjaTlCNlF2VnozVlM5MUw3Q0ZQNmJ4Vlc5SjNGcDIweFh1?=
 =?utf-8?B?Q3FTSFE0SS9SYTZpTThxMkVSUWZaUzBiYnQvQS9WdGFsa25lWFdoNFlpMUE1?=
 =?utf-8?B?SVpsZ2RzeVpGNlA4MXNVZnNSRU5XVS9FYm1EekdhZWZ1cTlBMFB5aTk2cFU2?=
 =?utf-8?B?Tk10bDNlNDZEN0g4a0FrUzV0bXFzNEZGaklpT1FBT05uMFlrb2p6czkzMm91?=
 =?utf-8?B?WllIdy9rKzBqd2lVYlI4bHczYXhmOEFSRzlqdUIwazMySm5RU3ZNZWE3WTZh?=
 =?utf-8?B?UnQrNUhscm4yQXoyN0c5NjRxazh3SEozMFlUSXpDWkZlU0dSVHY4cTNIbDRP?=
 =?utf-8?B?SWhadmZVcnNhZXR5ZWJ0MWZlYVE5OU1TSjJMdGxXR0wvVFNmelhLa3hUNVBR?=
 =?utf-8?B?L0xEWnFjN1BCYmtscElaSy9hRExpcmN3eGNXanRIYlhoS2RQQUxZeFdoMGo4?=
 =?utf-8?B?aGE5SVB4QjBvc3VkQmFOR2NmSjJEWi9IOFZjcFUrTW5pbjd5Uk81UUo3NXo2?=
 =?utf-8?B?eklLTkE4WjMxT1BLNWwxT2pocGNENjhlVW5VanorQ0k0Qm1PZzBhV3M4NHFB?=
 =?utf-8?B?L2NLUVNSQk9maitlczJyVUxwM1FWdTRwYkNmSFovRzZKemJoMmw2Zm8vNkMr?=
 =?utf-8?B?Ykt0cHE3S1kvdEQ5T2ovd2VFeVlvODNyZDQ0SC9MVU9hUWFEK0M5NHhtcUxj?=
 =?utf-8?B?d1E9PQ==?=
X-MS-Exchange-CrossTenant-Network-Message-Id: 907a0416-7170-4de1-dc63-08dc6325b26e
X-MS-Exchange-CrossTenant-AuthSource: CO1PR11MB5089.namprd11.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Apr 2024 23:41:13.9271
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: h0B9DlVHYuXEXWd09zjS/HYERtgdEvyVp90/jsA2dv6Rd2mqBmR0JvSxsGXBhaCnvnEHtMWZzBuIt1qVxiecHLOOyLVRE71OsncW3Rk2eUM=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH8PR11MB8258
X-OriginatorOrg: intel.com


On 4/22/2024 8:27 AM, Asbjørn Sloth Tønnesen wrote:
> Use flow_rule_is_supp_control_flags() to reject filters with
> unsupported control flags.
> 
> In case any unsupported control flags are masked,
> flow_rule_is_supp_control_flags() sets a NL extended
> error message, and we return -EOPNOTSUPP.
> 
> Remove FLOW_DIS_FIRST_FRAG specific error message,
> and treat it as any other unsupported control flag.
> 
> Only compile-tested.
> 
> Signed-off-by: Asbjørn Sloth Tønnesen <ast@fiberby.net>
> ---
>  drivers/net/ethernet/marvell/octeontx2/nic/otx2_tc.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_tc.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_tc.c
> index 6d4ce2ece8d0..e63cc1eb6d89 100644
> --- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_tc.c
> +++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_tc.c
> @@ -700,10 +700,6 @@ static int otx2_tc_prepare_flow(struct otx2_nic *nic, struct otx2_tc_flow *node,
>  		u32 val;
>  
>  		flow_rule_match_control(rule, &match);
> -		if (match.mask->flags & FLOW_DIS_FIRST_FRAG) {
> -			NL_SET_ERR_MSG_MOD(extack, "HW doesn't support frag first/later");
> -			return -EOPNOTSUPP;
> -		}
>  
>  		if (match.mask->flags & FLOW_DIS_IS_FRAGMENT) {
>  			val = match.key->flags & FLOW_DIS_IS_FRAGMENT;
> @@ -721,6 +717,10 @@ static int otx2_tc_prepare_flow(struct otx2_nic *nic, struct otx2_tc_flow *node,
>  				return -EOPNOTSUPP;
>  			}
>  		}
> +
> +		if (!flow_rule_is_supp_control_flags(FLOW_DIS_IS_FRAGMENT,
> +						     match.mask->flags, extack))
> +			return -EOPNOTSUPP;

This confuses me since you pass FLOW_DIS_IS_FRAGMENT here, but you
removed the check for FLOW_DIS_FIRST_FRAG??

Am I misunderstanding how flow_rule_is_supp_control_flags works?

The code just above this appears to support FLOW_DIS_IS_FRAGMENT.

Here is the implementation of flow_rule_is_supp_control_flags for reference:

> /**
>  * flow_rule_is_supp_control_flags() - check for supported control flags
>  * @supp_flags: control flags supported by driver
>  * @ctrl_flags: control flags present in rule
>  * @extack: The netlink extended ACK for reporting errors.
>  *
>  * Return: true if only supported control flags are set, false otherwise.
>  */
> static inline bool flow_rule_is_supp_control_flags(const u32 supp_flags,
>                                                    const u32 ctrl_flags,
>                                                    struct netlink_ext_ack *extack)
> {
>         if (likely((ctrl_flags & ~supp_flags) == 0))
>                 return true;
> 
>         NL_SET_ERR_MSG_FMT_MOD(extack,
>                                "Unsupported match on control.flags %#x",
>                                ctrl_flags);
> 
>         return false;
> }
> 

This seems to me that it you accidentally passed FLOW_DIS_IS_FRAGMENT
when you meant FLOW_DIS_FIRST_FRAG??

I also think its a bit strange that you moved the placement of the check
instead of replacing in the same location as where the previous check was.


>  	}
>  
>  	if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_ETH_ADDRS)) {