Add two no op instructions following swi for Go on openbsd/arm.

arm processors have the same speculative execution flaw that occurs across
a syscall boundary, which was previously addressed in the arm64 port.

lang/go/Makefile

@@ -1,4 +1,4 @@
-# $OpenBSD: Makefile,v 1.84 2020/03/06 15:26:18 espie Exp $
+# $OpenBSD: Makefile,v 1.85 2020/03/20 08:02:29 jsing Exp $
 
 ONLY_FOR_ARCHS =	${GO_ARCHS}
 
@@ -8,7 +8,7 @@ BIN_BOOTSTRAP_VERSION = 1.13.7
 COMMENT =		Go programming language
 
 VERSION =		1.13.7
-REVISION =		0
+REVISION =		1
 DISTNAME =		go${VERSION}.src
 PKGNAME =		go-${VERSION}
 PKGSPEC =		${FULLPKGNAME:S/go-/go-=/}

lang/go/patches/patch-src_runtime_sys_openbsd_arm_s

@@ -0,0 +1,263 @@
+$OpenBSD: patch-src_runtime_sys_openbsd_arm_s,v 1.3 2020/03/20 08:02:29 jsing Exp $
+
+Index: src/runtime/sys_openbsd_arm.s
+--- src/runtime/sys_openbsd_arm.s.orig
++++ src/runtime/sys_openbsd_arm.s
+@@ -13,11 +13,15 @@
+ #define CLOCK_REALTIME	$0
+ #define	CLOCK_MONOTONIC	$3
+ 
++#define NOOP   MOVW R0, R0
++
+ // Exit the entire program (like C exit)
+ TEXT runtime·exit(SB),NOSPLIT|NOFRAME,$0
+ 	MOVW	code+0(FP), R0	// arg 1 - status
+ 	MOVW	$1, R12			// sys_exit
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	MOVW.CS	$0, R8			// crash on syscall failure
+ 	MOVW.CS	R8, (R8)
+ 	RET
+@@ -27,6 +31,8 @@ TEXT runtime·exitThread(SB),NOSPLIT,$0-4
+ 	MOVW	wait+0(FP), R0		// arg 1 - notdead
+ 	MOVW	$302, R12		// sys___threxit
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	MOVW.CS	$1, R8			// crash on syscall failure
+ 	MOVW.CS	R8, (R8)
+ 	JMP	0(PC)
+@@ -37,6 +43,8 @@ TEXT runtime·open(SB),NOSPLIT|NOFRAME,$0
+ 	MOVW	perm+8(FP), R2		// arg 3 - perm
+ 	MOVW	$5, R12			// sys_open
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	MOVW.CS	$-1, R0
+ 	MOVW	R0, ret+12(FP)
+ 	RET
+@@ -45,6 +53,8 @@ TEXT runtime·closefd(SB),NOSPLIT|NOFRAME,$0
+ 	MOVW	fd+0(FP), R0		// arg 1 - fd
+ 	MOVW	$6, R12			// sys_close
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	MOVW.CS	$-1, R0
+ 	MOVW	R0, ret+4(FP)
+ 	RET
+@@ -55,6 +65,8 @@ TEXT runtime·read(SB),NOSPLIT|NOFRAME,$0
+ 	MOVW	n+8(FP), R2		// arg 3 - nbyte
+ 	MOVW	$3, R12			// sys_read
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	MOVW.CS	$-1, R0
+ 	MOVW	R0, ret+12(FP)
+ 	RET
+@@ -65,6 +77,8 @@ TEXT runtime·write(SB),NOSPLIT|NOFRAME,$0
+ 	MOVW	n+8(FP), R2		// arg 3 - nbyte
+ 	MOVW	$4, R12			// sys_write
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	MOVW.CS	$-1, R0
+ 	MOVW	R0, ret+12(FP)
+ 	RET
+@@ -83,25 +97,35 @@ TEXT runtime·usleep(SB),NOSPLIT,$16
+ 	MOVW	$0, R1			// arg 2 - rmtp
+ 	MOVW	$91, R12		// sys_nanosleep
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	RET
+ 
+ TEXT runtime·raise(SB),NOSPLIT,$12
+ 	MOVW	$299, R12		// sys_getthrid
+ 	SWI	$0
++	NOOP
++	NOOP
+ 					// arg 1 - tid, already in R0
+ 	MOVW	sig+0(FP), R1		// arg 2 - signum
+ 	MOVW	$0, R2			// arg 3 - tcb
+ 	MOVW	$119, R12		// sys_thrkill
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	RET
+ 
+ TEXT runtime·raiseproc(SB),NOSPLIT,$12
+ 	MOVW	$20, R12
+ 	SWI	$0			// sys_getpid
++	NOOP
++	NOOP
+ 					// arg 1 - pid, already in R0
+ 	MOVW	sig+0(FP), R1		// arg 2 - signum
+ 	MOVW	$122, R12		// sys_kill
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	RET
+ 
+ TEXT runtime·mmap(SB),NOSPLIT,$16
+@@ -120,6 +144,8 @@ TEXT runtime·mmap(SB),NOSPLIT,$16
+ 	ADD	$4, R13
+ 	MOVW	$197, R12		// sys_mmap
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	SUB	$4, R13
+ 	MOVW	$0, R1
+ 	MOVW.CS	R0, R1			// if error, move to R1
+@@ -133,6 +159,8 @@ TEXT runtime·munmap(SB),NOSPLIT,$0
+ 	MOVW	n+4(FP), R1		// arg 2 - len
+ 	MOVW	$73, R12		// sys_munmap
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	MOVW.CS	$0, R8			// crash on syscall failure
+ 	MOVW.CS	R8, (R8)
+ 	RET
+@@ -143,6 +171,8 @@ TEXT runtime·madvise(SB),NOSPLIT,$0
+ 	MOVW	flags+8(FP), R2		// arg 2 - flags
+ 	MOVW	$75, R12		// sys_madvise
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	MOVW.CS	$-1, R0
+ 	MOVW	R0, ret+12(FP)
+ 	RET
+@@ -153,6 +183,8 @@ TEXT runtime·setitimer(SB),NOSPLIT,$0
+ 	MOVW	old+8(FP), R2		// arg 3 - old value
+ 	MOVW	$69, R12		// sys_setitimer
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	RET
+ 
+ // func walltime() (sec int64, nsec int32)
+@@ -161,6 +193,8 @@ TEXT runtime·walltime(SB), NOSPLIT, $32
+ 	MOVW	$8(R13), R1		// arg 2 - tp
+ 	MOVW	$87, R12		// sys_clock_gettime
+ 	SWI	$0
++	NOOP
++	NOOP
+ 
+ 	MOVW	8(R13), R0		// sec - l32
+ 	MOVW	12(R13), R1		// sec - h32
+@@ -179,6 +213,8 @@ TEXT runtime·nanotime(SB),NOSPLIT,$32
+ 	MOVW	$8(R13), R1		// arg 2 - tp
+ 	MOVW	$87, R12		// sys_clock_gettime
+ 	SWI	$0
++	NOOP
++	NOOP
+ 
+ 	MOVW	8(R13), R0		// sec - l32
+ 	MOVW	12(R13), R4		// sec - h32
+@@ -200,6 +236,8 @@ TEXT runtime·sigaction(SB),NOSPLIT,$0
+ 	MOVW	old+8(FP), R2		// arg 3 - old sigaction
+ 	MOVW	$46, R12		// sys_sigaction
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	MOVW.CS	$3, R8			// crash on syscall failure
+ 	MOVW.CS	R8, (R8)
+ 	RET
+@@ -209,6 +247,8 @@ TEXT runtime·obsdsigprocmask(SB),NOSPLIT,$0
+ 	MOVW	new+4(FP), R1		// arg 2 - new
+ 	MOVW	$48, R12		// sys_sigprocmask
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	MOVW.CS	$3, R8			// crash on syscall failure
+ 	MOVW.CS	R8, (R8)
+ 	MOVW	R0, ret+8(FP)
+@@ -251,6 +291,8 @@ TEXT runtime·tfork(SB),NOSPLIT,$0
+ 	MOVW	psize+4(FP), R1		// arg 2 - psize
+ 	MOVW	$8, R12			// sys___tfork
+ 	SWI	$0
++	NOOP
++	NOOP
+ 
+ 	// Return if syscall failed.
+ 	B.CC	4(PC)
+@@ -284,6 +326,8 @@ TEXT runtime·sigaltstack(SB),NOSPLIT,$0
+ 	MOVW	old+4(FP), R1		// arg 2 - old sigaltstack
+ 	MOVW	$288, R12		// sys_sigaltstack
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	MOVW.CS	$0, R8			// crash on syscall failure
+ 	MOVW.CS	R8, (R8)
+ 	RET
+@@ -291,6 +335,8 @@ TEXT runtime·sigaltstack(SB),NOSPLIT,$0
+ TEXT runtime·osyield(SB),NOSPLIT,$0
+ 	MOVW	$298, R12		// sys_sched_yield
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	RET
+ 
+ TEXT runtime·thrsleep(SB),NOSPLIT,$4
+@@ -303,6 +349,8 @@ TEXT runtime·thrsleep(SB),NOSPLIT,$4
+ 	ADD	$4, R13
+ 	MOVW	$94, R12		// sys___thrsleep
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	SUB	$4, R13
+ 	MOVW	R0, ret+20(FP)
+ 	RET
+@@ -312,6 +360,8 @@ TEXT runtime·thrwakeup(SB),NOSPLIT,$0
+ 	MOVW	n+4(FP), R1		// arg 2 - n
+ 	MOVW	$301, R12		// sys___thrwakeup
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	MOVW	R0, ret+8(FP)
+ 	RET
+ 
+@@ -327,6 +377,8 @@ TEXT runtime·sysctl(SB),NOSPLIT,$8
+ 	ADD	$4, R13
+ 	MOVW	$202, R12		// sys___sysctl
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	SUB	$4, R13
+ 	MOVW.CC	$0, R0
+ 	RSB.CS	$0, R0
+@@ -337,6 +389,8 @@ TEXT runtime·sysctl(SB),NOSPLIT,$8
+ TEXT runtime·kqueue(SB),NOSPLIT,$0
+ 	MOVW	$269, R12		// sys_kqueue
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	RSB.CS	$0, R0
+ 	MOVW	R0, ret+0(FP)
+ 	RET
+@@ -354,6 +408,8 @@ TEXT runtime·kevent(SB),NOSPLIT,$8
+ 	ADD	$4, R13
+ 	MOVW	$72, R12		// sys_kevent
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	RSB.CS	$0, R0
+ 	SUB	$4, R13
+ 	MOVW	R0, ret+24(FP)
+@@ -366,6 +422,8 @@ TEXT runtime·closeonexec(SB),NOSPLIT,$0
+ 	MOVW	$1, R2			// arg 3 - arg (FD_CLOEXEC)
+ 	MOVW	$92, R12		// sys_fcntl
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	RET
+ 
+ TEXT ·publicationBarrier(SB),NOSPLIT|NOFRAME,$0-0
+@@ -375,5 +433,7 @@ TEXT runtime·read_tls_fallback(SB),NOSPLIT|NOFRAME,$0
+ 	MOVM.WP	[R1, R2, R3, R12], (R13)
+ 	MOVW	$330, R12		// sys___get_tcb
+ 	SWI	$0
++	NOOP
++	NOOP
+ 	MOVM.IAW (R13), [R1, R2, R3, R12]
+ 	RET

lang/go/patches/patch-src_syscall_asm_openbsd_arm_s

@@ -0,0 +1,59 @@
+$OpenBSD: patch-src_syscall_asm_openbsd_arm_s,v 1.1 2020/03/20 08:02:29 jsing Exp $
+
+Index: src/syscall/asm_openbsd_arm.s
+--- src/syscall/asm_openbsd_arm.s.orig
++++ src/syscall/asm_openbsd_arm.s
+@@ -15,6 +15,8 @@
+ // func RawSyscall(trap int32, a1, a2, a3 int32) (r1, r2, err int32);
+ // func RawSyscall6(trap int32, a1, a2, a3, a4, a5, a6 int32) (r1, r2, err int32);
+ 
++#define NOOP   MOVW R0, R0
++
+ TEXT	·Syscall(SB),NOSPLIT,$0-28
+ 	BL runtime·entersyscall(SB)
+ 	MOVW trap+0(FP), R12		// syscall number
+@@ -22,6 +24,8 @@ TEXT	·Syscall(SB),NOSPLIT,$0-28
+ 	MOVW a2+8(FP), R1		// arg 2
+ 	MOVW a3+12(FP), R2		// arg 3
+ 	SWI $0
++	NOOP
++	NOOP
+ 	MOVW $0, R2
+ 	BCS error
+ 	MOVW R0, r1+16(FP)		// ret 1
+@@ -47,6 +51,8 @@ TEXT	·Syscall6(SB),NOSPLIT,$0-40
+ 	MOVW R13, R4
+ 	MOVW $a5+20(FP), R13		// arg 5 to arg 6 are passed on stack
+ 	SWI $0
++	NOOP
++	NOOP
+ 	MOVW R4, R13
+ 	MOVW $0, R2
+ 	BCS error6
+@@ -73,6 +79,8 @@ TEXT	·Syscall9(SB),NOSPLIT,$0-52
+ 	MOVW R13, R4
+ 	MOVW $a5+20(FP), R13		// arg 5 to arg 9 are passed on stack
+ 	SWI $0
++	NOOP
++	NOOP
+ 	MOVW R4, R13
+ 	MOVW $0, R2
+ 	BCS error9
+@@ -95,6 +103,8 @@ TEXT	·RawSyscall(SB),NOSPLIT,$0-28
+ 	MOVW a2+8(FP), R1		// arg 2
+ 	MOVW a3+12(FP), R2		// arg 3
+ 	SWI $0
++	NOOP
++	NOOP
+ 	MOVW $0, R2
+ 	BCS errorr
+ 	MOVW R0, r1+16(FP)		// ret 1
+@@ -117,6 +127,8 @@ TEXT	·RawSyscall6(SB),NOSPLIT,$0-40
+ 	MOVW R13, R4
+ 	MOVW $a5+20(FP), R13		// arg 5 to arg 6 are passed on stack
+ 	SWI $0
++	NOOP
++	NOOP
+ 	MOVW R4, R13
+ 	MOVW $0, R2
+ 	BCS errorr6