Deadlock on remote -- rcu_read_lock_sched held

[bxatnarf]

Arch: x86<->x86,

Config:

CONFIG_ARCH_SUPPORTS_POPCORN=y
CONFIG_POPCORN=y
CONFIG_POPCORN_DEBUG=y
# CONFIG_POPCORN_DEBUG_PROCESS_SERVER is not set
# CONFIG_POPCORN_DEBUG_PAGE_SERVER is nohttps://github.com/ssrg-vt/popcorn-kernel/issues/newt set
# CONFIG_POPCORN_DEBUG_VMA_SERVER is not set
# CONFIG_POPCORN_DEBUG_VERBOSE is not set
CONFIG_POPCORN_CHECK_SANITY=y
CONFIG_POPCORN_REMOTE_INFO=y
# CONFIG_POPCORN_STAT is not set
CONFIG_POPCORN_KMSG=y
CONFIG_POPCORN_KMSG_SOCKET=m
# CONFIG_POPCORN_KMSG_TEST is not set
# CONFIG_POPCORN_DEBUG_MSG_LAYER is not set

(will finish writing this up later)