ioctl(FIONREAD) failed to return correct length in SRIOV environment for IPv6

Solution In Progress - Updated 2024-06-14T18:45:42+00:00 -

Issue

ioctl(FIONREAD) failed to return correct length in SRIOV environment for IPv6
An application runs in a VM with Intel 82599 SR-IOV VF (ixgbevf). This application opens a socket(AF_INET6, SOCK_RAW, IPPROTO_SCTP); and enters that socket into a select() read set, then when FD_ISSET() fires, checks the data to be received with ioctl(FIONREAD) then receives the data with recvfrom(). However, with RHEL 6.8 or 6.9, the ioctl() returns zero bytes ready forever.

Red Hat Enterprise Linux 6.8 (2.6.32-642.3.1) and 6.9 (2.6.32-696)
KVM guest
SR-IOV Virtual Function using Intel ixgbevf driver
IPv6 raw socket
Socket polling with select() or poll() or epoll()
ioctl(FIONREAD) or ioctl(SIOCINQ) to check bytes available on notified socket

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