Noticed this over on Master the other day after rpcd 2.40 was updated...
Haven't had much of a chance to dig into it yet - happens on luci login
Sat Jan 21 14:25:22 2023 daemon.err uhttpd[2243]: [info] luci: accepted login on / for root from 192.168.1.147
Sat Jan 21 14:25:26 2023 kern.info kernel: [ 411.731549] do_page_fault(): sending SIGSEGV to rpcd for invalid read access from 0000000c
Sat Jan 21 14:25:26 2023 kern.info kernel: [ 411.738686] epc = 77e01483 in libubox.so.20220927[77dfe000+1f000]
Sat Jan 21 14:25:26 2023 kern.info kernel: [ 411.744497] ra = 77c9b385 in luci.so[77c9a000+1f000]