Vishnu Dasa
2023-Mar-29 21:44 UTC
[RFC PATCH v1 1/2] vsock: return errors other than -ENOMEM to socket
> On Mar 28, 2023, at 4:20 AM, Arseniy Krasnov <AVKrasnov at sberdevices.ru> wrote: > > !! External Email > > On 28.03.2023 14:19, Stefano Garzarella wrote: >> On Tue, Mar 28, 2023 at 01:42:19PM +0300, Arseniy Krasnov wrote: >>> >>> >>> On 28.03.2023 12:42, Stefano Garzarella wrote: >>>> I pressed send too early... >>>> >>>> CCing Bryan, Vishnu, and pv-drivers at vmware.com >>>> >>>> On Tue, Mar 28, 2023 at 11:39?AM Stefano Garzarella <sgarzare at redhat.com> wrote: >>>>> >>>>> On Sun, Mar 26, 2023 at 01:13:11AM +0300, Arseniy Krasnov wrote: >>>>>> This removes behaviour, where error code returned from any transport >>>>>> was always switched to ENOMEM. This works in the same way as: >>>>>> commit >>>>>> c43170b7e157 ("vsock: return errors other than -ENOMEM to socket"), >>>>>> but for receive calls. >>>>>> >>>>>> Signed-off-by: Arseniy Krasnov <AVKrasnov at sberdevices.ru> >>>>>> --- >>>>>> net/vmw_vsock/af_vsock.c | 4 ++-- >>>>>> 1 file changed, 2 insertions(+), 2 deletions(-) >>>>>> >>>>>> diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c >>>>>> index 19aea7cba26e..9262e0b77d47 100644 >>>>>> --- a/net/vmw_vsock/af_vsock.c >>>>>> +++ b/net/vmw_vsock/af_vsock.c >>>>>> @@ -2007,7 +2007,7 @@ static int __vsock_stream_recvmsg(struct sock *sk, struct msghdr *msg, >>>>>> >>>>>> read = transport->stream_dequeue(vsk, msg, len - copied, flags); >>>>> >>>>> In vmci_transport_stream_dequeue() vmci_qpair_peekv() and >>>>> vmci_qpair_dequev() return VMCI_ERROR_* in case of errors. >>>>> >>>>> Maybe we should return -ENOMEM in vmci_transport_stream_dequeue() if >>>>> those functions fail to keep the same behavior. >>> >>> Yes, seems i missed it, because several months ago we had similar question for send >>> logic: >>> https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.spinics.net%2Flists%2Fkernel%2Fmsg4611091.html&data=05%7C01%7Cvdasa%40vmware.com%7C3b17793425384debe75708db2f7eec8c%7Cb39138ca3cee4b4aa4d6cd83d9dd62f0%7C0%7C0%7C638155994413494900%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=MMfFcKuFFvMcJrbToKvWvIB%2FZmzp%2BdGGVWFVWztuSzg%3D&reserved=0 >>> And it was ok to not handle VMCI send path in this way. So i think current implementation >>> for tx is a little bit buggy, because VMCI specific error from 'vmci_qpair_enquev()' is >>> returned to af_vsock.c. I think error conversion must be added to VMCI transport for tx >>> also. >> >> Good point! >> >> These are negative values, so there are no big problems, but I don't >> know what the user expects in this case. >> >> @Vishnu Do we want to return an errno to the user or a VMCI_ERROR_*? > > Small remark, as i can see, VMCI_ERROR_ is not exported to user in include/uapi, > so IIUC user won't be able to interpret such values correctly. > > Thanks, ArseniyLet's just return -ENOMEM from vmci transport in case of error in vmci_transport_stream_enqueue and vmci_transport_stream_dequeue. @Arseniy, Could you please add a separate patch in this set to handle the above? Thanks, Vishnu> >> >> In both cases I think we should do the same for both enqueue and >> dequeue. >> >>> >>> Good thing is that Hyper-V uses general error codes. >> >> Yeah! >> >> Thanks, >> Stefano >> >>> >>> Thanks, Arseniy >>>>> >>>>> CCing Bryan, Vishnu, and pv-drivers at vmware.com >>>>> >>>>> The other transports seem okay to me. >>>>> >>>>> Thanks, >>>>> Stefano >>>>> >>>>>> if (read < 0) { >>>>>> - err = -ENOMEM; >>>>>> + err = read; >>>>>> break; >>>>>> } >>>>>> >>>>>> @@ -2058,7 +2058,7 @@ static int __vsock_seqpacket_recvmsg(struct sock *sk, struct msghdr *msg, >>>>>> msg_len = transport->seqpacket_dequeue(vsk, msg, flags); >>>>>> >>>>>> if (msg_len < 0) { >>>>>> - err = -ENOMEM; >>>>>> + err = msg_len; >>>>>> goto out; >>>>>> } >>>>>> >>>>>> -- >>>>>> 2.25.1 >>>>>> >>>> >>> >> > > !! External Email: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender.