remove support for syscall(2) -- the "indirection system call" because

it is a dangerous alternative entry point for all system calls, and thus
incompatible with the precision system call entry point scheme we are
heading towards.  This has been a 3-year mission:
First perl needed a code-generated wrapper to fake syscall(2) as a giant
switch table, then all the ports were cleaned with relatively minor fixes,
except for "go".  "go" required two fixes -- 1) a framework issue with
old library versions, and 2) like perl, a fake syscall(2) wrapper to
handle ioctl(2) and sysctl(2) because "syscall(SYS_ioctl" occurs all over
the place in the "go" ecosystem because the "go developers" are plan9-loving
unix-hating folk who tried to build an ecosystem without allowing "ioctl".
ok kettenis, jsing, afresh1, sthen

1 files changed, 9 insertions, 24 deletions

diff --git a/sys/arch/alpha/alpha/trap.c b/sys/arch/alpha/alpha/trap.c
index abe69405852..fc697aadf41 100644
--- a/sys/arch/alpha/alpha/trap.c
+++ b/sys/arch/alpha/alpha/trap.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: trap.c,v 1.108 2023/03/08 04:43:07 guenther Exp $ */
+/* $OpenBSD: trap.c,v 1.109 2023/12/12 15:30:55 deraadt Exp $ */
 /* $NetBSD: trap.c,v 1.52 2000/05/24 16:48:33 thorpej Exp $ */
 
 /*-
@@ -497,17 +497,15 @@ dopanic:
  * a3, and v0 from the frame before returning to the user process.
  */
 void
-syscall(code, framep)
-	u_int64_t code;
-	struct trapframe *framep;
+syscall(u_int64_t code, struct trapframe *framep)
 {
-	const struct sysent *callp;
+	const struct sysent *callp = sysent;
 	struct proc *p;
-	int error, indirect = -1;
+	int error;
 	u_int64_t opc;
 	u_long rval[2];
 	u_long args[10];					/* XXX */
-	u_int hidden, nargs;
+	u_int nargs;
 
 	atomic_add_int(&uvmexp.syscalls, 1);
 	p = curproc;
@@ -515,24 +513,11 @@ syscall(code, framep)
 	framep->tf_regs[FRAME_SP] = alpha_pal_rdusp();
 	opc = framep->tf_regs[FRAME_PC] - 4;
 
-	switch(code) {
-	case SYS_syscall:
-		indirect = code;
-		code = framep->tf_regs[FRAME_A0];
-		hidden = 1;
-		break;
-	default:
-		hidden = 0;
-	}
-
-	error = 0;
-	callp = sysent;
-	if (code >= SYS_MAXSYSCALL)
-		callp += SYS_syscall;
-	else
+	// XXX out of range stays on syscall0, which we assume is enosys
+	if (code >= 0 || code <= SYS_MAXSYSCALL)
 		callp += code;
 
-	nargs = callp->sy_narg + hidden;
+	nargs = callp->sy_narg;
 	switch (nargs) {
 	default:
 		if (nargs > 10)		/* XXX */
@@ -559,7 +544,7 @@ syscall(code, framep)
 	rval[0] = 0;
 	rval[1] = 0;
 
-	error = mi_syscall(p, code, indirect, callp, args + hidden, rval);
+	error = mi_syscall(p, code, callp, args, rval);
 
 	switch (error) {
 	case 0: