runtime: stack split at a bad time on mipsle #21431
Description
Recent build failure from the dashboard (linux-mipsle at 816deac
): https://build.golang.org/log/e101d6d552cc5dce1ebf5b5560c0b399dbe86f6e
runtime: newstack sp=0x8861994 stack=[0x8861000, 0x8862000]
morebuf={pc:0x93440 sp:0x8861994 lr:0x0}
sched={pc:0x55e3c sp:0x8861994 lr:0x93440 ctxt:0x0}
syscall.Syscall(0x90010, 0xfa3, 0x5, 0x8861a0c, 0x4, 0x0, 0x0)
/usr/local/go-bootstrap-mipsle/src/syscall/asm_linux_mipsx.s:31 +0x58
syscall.readlen(0x19, 0x0, 0x888e780, 0x8861ac8, 0x234960, 0x6)
/usr/local/go-bootstrap-mipsle/src/syscall/zsyscall_linux_mipsle.go:1050 +0x5c
created by main.cmdbootstrap
/data/mipsle/go/src/cmd/dist/build.go:1071 +0x498
fatal error: runtime: stack split at bad time
[stack traces]