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Tsirkin" Cc: eperezma@redhat.com, sgarzare@redhat.com, mjrosato@linux.ibm.com, qemu-devel@nongnu.org References: <20250211161923.1477960-1-kshk@linux.ibm.com> <20250220105323-mutt-send-email-mst@kernel.org> Content-Language: en-US From: Konstantin Shkolnyy In-Reply-To: <20250220105323-mutt-send-email-mst@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: HShCxkvKOA0i2LgE5_pthQDyBwdqTF3c X-Proofpoint-ORIG-GUID: HShCxkvKOA0i2LgE5_pthQDyBwdqTF3c X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1057,Hydra:6.0.680,FMLib:17.12.68.34 definitions=2025-02-20_09,2025-02-20_02,2024-11-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=999 malwarescore=0 clxscore=1015 lowpriorityscore=0 suspectscore=0 impostorscore=0 priorityscore=1501 phishscore=0 adultscore=0 mlxscore=0 bulkscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2502100000 definitions=main-2502210023 Received-SPF: pass client-ip=148.163.158.5; envelope-from=kshk@linux.ibm.com; helo=mx0b-001b2d01.pphosted.com X-Spam_score_int: -26 X-Spam_score: -2.7 X-Spam_bar: -- X-Spam_report: (-2.7 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 2/20/2025 09:57, Michael S. Tsirkin wrote: > On Tue, Feb 11, 2025 at 10:19:23AM -0600, Konstantin Shkolnyy wrote: >> Add .set_vnet_le() function that always returns success, assuming that >> vDPA h/w always implements LE data format. Otherwise, QEMU disables vDPA and >> outputs the message: >> "backend does not support LE vnet headers; falling back on userspace virtio" >> >> Signed-off-by: Konstantin Shkolnyy > > Thanks for the patch! Yet something to improve: > > >> --- >> net/vhost-vdpa.c | 6 ++++++ >> 1 file changed, 6 insertions(+) >> >> diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c >> index 231b45246c..7219aa2eee 100644 >> --- a/net/vhost-vdpa.c >> +++ b/net/vhost-vdpa.c >> @@ -270,6 +270,11 @@ static bool vhost_vdpa_has_ufo(NetClientState *nc) >> >> } >> >> +static int vhost_vdpa_set_vnet_le(NetClientState *nc, bool is_le) >> +{ >> + return 0; > > How about checking is_le is true then? As I understand, the control comes here from virtio_net_set_vnet_endian(...., bool enable). That "enable" is copied into the "is_le" here. Thus, it doesn't look like "is_le = false" means BE. Rather, it looks like it means "default endianness of the NetClient". If so, the function should probably just return 0 in both cases. I think, that is also why we have .set_vnet_le() and .set_vnet_be() instead of just one function. If the above is correct, maybe I should rename "is_le" into "enable"? (I simply copied the name from another function...) > And add a code comment with an explanation, please. Sure.