Get rid of sa->narg. It serves no purpose; use sa->callp->sy_narg instead.

Reviewed by:	kib
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D26458

29 files changed, 50 insertions, 73 deletions

diff --git a/sys/amd64/amd64/trap.c b/sys/amd64/amd64/trap.c
index 01656a48c105..01519d9a7c16 100644
--- a/sys/amd64/amd64/trap.c
+++ b/sys/amd64/amd64/trap.c
@@ -999,15 +999,15 @@ cpu_fetch_syscall_args_fallback(struct thread *td, struct syscall_args *sa)
   	else
  		sa->callp = &p->p_sysent->sv_table[sa->code];
 
-	sa->narg = sa->callp->sy_narg;
-	KASSERT(sa->narg <= nitems(sa->args), ("Too many syscall arguments!"));
+	KASSERT(sa->callp->sy_narg <= nitems(sa->args),
+	    ("Too many syscall arguments!"));
 	argp = &frame->tf_rdi;
 	argp += reg;
 	memcpy(sa->args, argp, sizeof(sa->args[0]) * NARGREGS);
-	if (sa->narg > regcnt) {
+	if (sa->callp->sy_narg > regcnt) {
 		params = (caddr_t)frame->tf_rsp + sizeof(register_t);
 		error = copyin(params, &sa->args[regcnt],
-	    	    (sa->narg - regcnt) * sizeof(sa->args[0]));
+	    	    (sa->callp->sy_narg - regcnt) * sizeof(sa->args[0]));
 		if (__predict_false(error != 0))
 			return (error);
 	}
@@ -1037,10 +1037,10 @@ cpu_fetch_syscall_args(struct thread *td)
 		return (cpu_fetch_syscall_args_fallback(td, sa));
 
 	sa->callp = &p->p_sysent->sv_table[sa->code];
-	sa->narg = sa->callp->sy_narg;
-	KASSERT(sa->narg <= nitems(sa->args), ("Too many syscall arguments!"));
+	KASSERT(sa->callp->sy_narg <= nitems(sa->args),
+	    ("Too many syscall arguments!"));
 
-	if (__predict_false(sa->narg > NARGREGS))
+	if (__predict_false(sa->callp->sy_narg > NARGREGS))
 		return (cpu_fetch_syscall_args_fallback(td, sa));
 
 	memcpy(sa->args, &frame->tf_rdi, sizeof(sa->args[0]) * NARGREGS);
diff --git a/sys/amd64/cloudabi32/cloudabi32_sysvec.c b/sys/amd64/cloudabi32/cloudabi32_sysvec.c
index 5d21426e3ee9..5f04c35a5c72 100644
--- a/sys/amd64/cloudabi32/cloudabi32_sysvec.c
+++ b/sys/amd64/cloudabi32/cloudabi32_sysvec.c
@@ -104,7 +104,6 @@ cloudabi32_fetch_syscall_args(struct thread *td)
 	if (sa->code >= CLOUDABI32_SYS_MAXSYSCALL)
 		return (ENOSYS);
 	sa->callp = &cloudabi32_sysent[sa->code];
-	sa->narg = sa->callp->sy_narg;
 
 	/*
 	 * Fetch system call arguments.
@@ -117,7 +116,7 @@ cloudabi32_fetch_syscall_args(struct thread *td)
 	 * implementation used by 64-bit processes.
 	 */
 	error = copyin((void *)frame->tf_rcx, sa->args,
-	    sa->narg * sizeof(sa->args[0]));
+	    sa->callp->sy_narg * sizeof(sa->args[0]));
 	if (error != 0)
 		return (error);
 
diff --git a/sys/amd64/cloudabi64/cloudabi64_sysvec.c b/sys/amd64/cloudabi64/cloudabi64_sysvec.c
index c3455edb55bb..34ad0aedfe8b 100644
--- a/sys/amd64/cloudabi64/cloudabi64_sysvec.c
+++ b/sys/amd64/cloudabi64/cloudabi64_sysvec.c
@@ -101,7 +101,6 @@ cloudabi64_fetch_syscall_args(struct thread *td)
 	if (sa->code >= CLOUDABI64_SYS_MAXSYSCALL)
 		return (ENOSYS);
 	sa->callp = &cloudabi64_sysent[sa->code];
-	sa->narg = sa->callp->sy_narg;
 
 	/* Fetch system call arguments. */
 	sa->args[0] = frame->tf_rdi;
diff --git a/sys/amd64/ia32/ia32_syscall.c b/sys/amd64/ia32/ia32_syscall.c
index 4d08cfb43b63..6c9399d1a52f 100644
--- a/sys/amd64/ia32/ia32_syscall.c
+++ b/sys/amd64/ia32/ia32_syscall.c
@@ -180,15 +180,14 @@ ia32_fetch_syscall_args(struct thread *td)
  		sa->callp = &p->p_sysent->sv_table[0];
   	else
  		sa->callp = &p->p_sysent->sv_table[sa->code];
-	sa->narg = sa->callp->sy_narg;
 
-	if (params != NULL && sa->narg != 0)
+	if (params != NULL && sa->callp->sy_narg != 0)
 		error = copyin(params, (caddr_t)args,
-		    (u_int)(sa->narg * sizeof(int)));
+		    (u_int)(sa->callp->sy_narg * sizeof(int)));
 	else
 		error = 0;
 
-	for (i = 0; i < sa->narg; i++)
+	for (i = 0; i < sa->callp->sy_narg; i++)
 		sa->args[i] = args[i];
 
 	if (error == 0) {
diff --git a/sys/amd64/include/proc.h b/sys/amd64/include/proc.h
index e74f1626a56a..59796e729ac4 100644
--- a/sys/amd64/include/proc.h
+++ b/sys/amd64/include/proc.h
@@ -94,7 +94,6 @@ struct syscall_args {
 	u_int code;
 	struct sysent *callp;
 	register_t args[8];
-	int narg;
 };
 
 #ifdef	_KERNEL
diff --git a/sys/amd64/linux/linux_sysvec.c b/sys/amd64/linux/linux_sysvec.c
index 927d423e38ae..3c578b36eac7 100644
--- a/sys/amd64/linux/linux_sysvec.c
+++ b/sys/amd64/linux/linux_sysvec.c
@@ -198,7 +198,6 @@ linux_fetch_syscall_args(struct thread *td)
 		sa->callp = &p->p_sysent->sv_table[p->p_sysent->sv_size - 1];
 	else
 		sa->callp = &p->p_sysent->sv_table[sa->code];
-	sa->narg = sa->callp->sy_narg;
 
 	td->td_retval[0] = 0;
 	return (0);
diff --git a/sys/amd64/linux32/linux32_sysvec.c b/sys/amd64/linux32/linux32_sysvec.c
index 7bb0aeb59209..2109f551a557 100644
--- a/sys/amd64/linux32/linux32_sysvec.c
+++ b/sys/amd64/linux32/linux32_sysvec.c
@@ -662,7 +662,6 @@ linux32_fetch_syscall_args(struct thread *td)
 		sa->callp = &p->p_sysent->sv_table[p->p_sysent->sv_size - 1];
 	else
 		sa->callp = &p->p_sysent->sv_table[sa->code];
-	sa->narg = sa->callp->sy_narg;
 
 	td->td_retval[0] = 0;
 	td->td_retval[1] = frame->tf_rdx;
diff --git a/sys/arm/arm/syscall.c b/sys/arm/arm/syscall.c
index 16a78868faaa..3d39e3ef59d9 100644
--- a/sys/arm/arm/syscall.c
+++ b/sys/arm/arm/syscall.c
@@ -120,12 +120,12 @@ cpu_fetch_syscall_args(struct thread *td)
 		sa->callp = &p->p_sysent->sv_table[0];
 	else
 		sa->callp = &p->p_sysent->sv_table[sa->code];
-	sa->narg = sa->callp->sy_narg;
 	error = 0;
 	memcpy(sa->args, ap, sa->nap * sizeof(register_t));
-	if (sa->narg > sa->nap) {
+	if (sa->callp->sy_narg > sa->nap) {
 		error = copyin((void *)td->td_frame->tf_usr_sp, sa->args +
-		    sa->nap, (sa->narg - sa->nap) * sizeof(register_t));
+		    sa->nap, (sa->callp->sy_narg - sa->nap) *
+		    sizeof(register_t));
 	}
 	if (error == 0) {
 		td->td_retval[0] = 0;
diff --git a/sys/arm/cloudabi32/cloudabi32_sysvec.c b/sys/arm/cloudabi32/cloudabi32_sysvec.c
index 26845fdbde46..c6dfe0661b7c 100644
--- a/sys/arm/cloudabi32/cloudabi32_sysvec.c
+++ b/sys/arm/cloudabi32/cloudabi32_sysvec.c
@@ -81,16 +81,15 @@ cloudabi32_fetch_syscall_args(struct thread *td)
 	if (sa->code >= CLOUDABI32_SYS_MAXSYSCALL)
 		return (ENOSYS);
 	sa->callp = &cloudabi32_sysent[sa->code];
-	sa->narg = sa->callp->sy_narg;
 
 	/* Fetch system call arguments from registers and the stack. */
 	sa->args[0] = frame->tf_r0;
 	sa->args[1] = frame->tf_r1;
 	sa->args[2] = frame->tf_r2;
 	sa->args[3] = frame->tf_r3;
-	if (sa->narg > 4) {
+	if (sa->callp->sy_narg > 4) {
 		error = copyin((void *)td->td_frame->tf_usr_sp, &sa->args[4],
-		    (sa->narg - 4) * sizeof(register_t));
+		    (sa->callp->sy_narg - 4) * sizeof(register_t));
 		if (error != 0)
 			return (error);
 	}
diff --git a/sys/arm/include/proc.h b/sys/arm/include/proc.h
index 94855b6f60e7..6baa6e5ed676 100644
--- a/sys/arm/include/proc.h
+++ b/sys/arm/include/proc.h
@@ -82,7 +82,6 @@ struct syscall_args {
 	u_int code;
 	struct sysent *callp;
 	register_t args[MAXARGS];
-	int narg;
 	u_int nap;
 } __aligned(8);
 
diff --git a/sys/arm64/arm64/elf32_machdep.c b/sys/arm64/arm64/elf32_machdep.c
index 35af2e5e070e..929380348aa8 100644
--- a/sys/arm64/arm64/elf32_machdep.c
+++ b/sys/arm64/arm64/elf32_machdep.c
@@ -156,7 +156,7 @@ freebsd32_fetch_syscall_args(struct thread *td)
 	struct proc *p;
 	register_t *ap;
 	struct syscall_args *sa;
-	int error, i, nap;
+	int error, i, nap, narg;
 	unsigned int args[4];
 
 	nap = 4;
@@ -181,15 +181,15 @@ freebsd32_fetch_syscall_args(struct thread *td)
 	else
 		sa->callp = &p->p_sysent->sv_table[sa->code];
 
-	sa->narg = sa->callp->sy_narg;
+	narg = sa->callp->sy_narg;
 	for (i = 0; i < nap; i++)
 		sa->args[i] = ap[i];
-	if (sa->narg > nap) {
-		if ((sa->narg - nap) > nitems(args))
+	if (narg > nap) {
+		if (narg - nap > nitems(args))
 			panic("Too many system call arguiments");
 		error = copyin((void *)td->td_frame->tf_x[13], args,
-		    (sa->narg - nap) * sizeof(int));
-		for (i = 0; i < (sa->narg - nap); i++)
+		    (narg - nap) * sizeof(int));
+		for (i = 0; i < (narg - nap); i++)
 			sa->args[i + nap] = args[i];
 	}
 
diff --git a/sys/arm64/arm64/trap.c b/sys/arm64/arm64/trap.c
index f3785dd702ed..f125025b0c61 100644
--- a/sys/arm64/arm64/trap.c
+++ b/sys/arm64/arm64/trap.c
@@ -127,7 +127,7 @@ cpu_fetch_syscall_args(struct thread *td)
 	struct syscall_args *sa;
 	int nap;
 
-	nap = 8;
+	nap = MAXARGS;
 	p = td->td_proc;
 	ap = td->td_frame->tf_x;
 	sa = &td->td_sa;
@@ -144,10 +144,9 @@ cpu_fetch_syscall_args(struct thread *td)
 	else
 		sa->callp = &p->p_sysent->sv_table[sa->code];
 
-	sa->narg = sa->callp->sy_narg;
 	memcpy(sa->args, ap, nap * sizeof(register_t));
-	if (sa->narg > nap)
-		panic("ARM64TODO: Could we have more than 8 args?");
+	if (sa->callp->sy_narg > nap)
+		panic("ARM64TODO: Could we have more than %d args?", MAXARGS);
 
 	td->td_retval[0] = 0;
 	td->td_retval[1] = 0;
diff --git a/sys/arm64/cloudabi32/cloudabi32_sysvec.c b/sys/arm64/cloudabi32/cloudabi32_sysvec.c
index 96d9432ff368..eb8c51742dc7 100644
--- a/sys/arm64/cloudabi32/cloudabi32_sysvec.c
+++ b/sys/arm64/cloudabi32/cloudabi32_sysvec.c
@@ -78,7 +78,6 @@ cloudabi32_fetch_syscall_args(struct thread *td)
 	if (sa->code >= CLOUDABI32_SYS_MAXSYSCALL)
 		return (ENOSYS);
 	sa->callp = &cloudabi32_sysent[sa->code];
-	sa->narg = sa->callp->sy_narg;
 
 	/*
 	 * Fetch system call arguments.
@@ -91,7 +90,7 @@ cloudabi32_fetch_syscall_args(struct thread *td)
 	 * implementation used by 64-bit processes.
 	 */
 	error = copyin((void *)frame->tf_x[2], sa->args,
-	    sa->narg * sizeof(sa->args[0]));
+	    sa->callp->sy_narg * sizeof(sa->args[0]));
 	if (error != 0)
 		return (error);
 
diff --git a/sys/arm64/cloudabi64/cloudabi64_sysvec.c b/sys/arm64/cloudabi64/cloudabi64_sysvec.c
index a493774551cf..92deb356a112 100644
--- a/sys/arm64/cloudabi64/cloudabi64_sysvec.c
+++ b/sys/arm64/cloudabi64/cloudabi64_sysvec.c
@@ -81,7 +81,6 @@ cloudabi64_fetch_syscall_args(struct thread *td)
 	if (sa->code >= CLOUDABI64_SYS_MAXSYSCALL)
 		return (ENOSYS);
 	sa->callp = &cloudabi64_sysent[sa->code];
-	sa->narg = sa->callp->sy_narg;
 
 	/* Fetch system call arguments. */
 	for (i = 0; i < MAXARGS; i++)
diff --git a/sys/arm64/include/proc.h b/sys/arm64/include/proc.h
index a844bfc64bcc..bb933dc98241 100644
--- a/sys/arm64/include/proc.h
+++ b/sys/arm64/include/proc.h
@@ -51,7 +51,6 @@ struct syscall_args {
 	u_int code;
 	struct sysent *callp;
 	register_t args[MAXARGS];
-	int narg;
 };
 
 #ifdef _KERNEL
diff --git a/sys/arm64/linux/linux_sysvec.c b/sys/arm64/linux/linux_sysvec.c
index 41652454cfc0..b7a80c7b4333 100644
--- a/sys/arm64/linux/linux_sysvec.c
+++ b/sys/arm64/linux/linux_sysvec.c
@@ -126,10 +126,9 @@ linux_fetch_syscall_args(struct thread *td)
 	else
 		sa->callp = &p->p_sysent->sv_table[sa->code];
 
-	sa->narg = sa->callp->sy_narg;
-	if (sa->narg > 8)
-		panic("ARM64TODO: Could we have more than 8 args?");
-	memcpy(sa->args, ap, 8 * sizeof(register_t));
+	if (sa->callp->sy_narg > MAXARGS)
+		panic("ARM64TODO: Could we have more than %d args?", MAXARGS);
+	memcpy(sa->args, ap, MAXARGS * sizeof(register_t));
 
 	td->td_retval[0] = 0;
 	return (0);
diff --git a/sys/i386/cloudabi32/cloudabi32_sysvec.c b/sys/i386/cloudabi32/cloudabi32_sysvec.c
index 76cab063501d..4f12d2b6cbce 100644
--- a/sys/i386/cloudabi32/cloudabi32_sysvec.c
+++ b/sys/i386/cloudabi32/cloudabi32_sysvec.c
@@ -99,11 +99,10 @@ cloudabi32_fetch_syscall_args(struct thread *td)
 	if (sa->code >= CLOUDABI32_SYS_MAXSYSCALL)
 		return (ENOSYS);
 	sa->callp = &cloudabi32_sysent[sa->code];
-	sa->narg = sa->callp->sy_narg;
 
 	/* Fetch system call arguments from the stack. */
 	error = copyin((void *)(frame->tf_esp + 4), sa->args,
-	    sa->narg * sizeof(sa->args[0]));
+	    sa->callp->sy_narg * sizeof(sa->args[0]));
 	if (error != 0)
 		return (error);
 
diff --git a/sys/i386/i386/trap.c b/sys/i386/i386/trap.c
index dd1ea0d1907e..6fd2a1393761 100644
--- a/sys/i386/i386/trap.c
+++ b/sys/i386/i386/trap.c
@@ -1084,11 +1084,10 @@ cpu_fetch_syscall_args(struct thread *td)
  		sa->callp = &p->p_sysent->sv_table[0];
   	else
  		sa->callp = &p->p_sysent->sv_table[sa->code];
-	sa->narg = sa->callp->sy_narg;
 
-	if (params != NULL && sa->narg != 0)
+	if (params != NULL && sa->callp->sy_narg != 0)
 		error = copyin(params, (caddr_t)sa->args,
-		    (u_int)(sa->narg * sizeof(uint32_t)));
+		    (u_int)(sa->callp->sy_narg * sizeof(uint32_t)));
 	else
 		error = 0;
 
diff --git a/sys/i386/include/proc.h b/sys/i386/include/proc.h
index 71b199603f51..2950946ff155 100644
--- a/sys/i386/include/proc.h
+++ b/sys/i386/include/proc.h
@@ -66,7 +66,6 @@ struct syscall_args {
 	u_int code;
 	struct sysent *callp;
 	register_t args[8];
-	int narg;
 };
 
 #ifdef	_KERNEL
diff --git a/sys/i386/linux/linux_sysvec.c b/sys/i386/linux/linux_sysvec.c
index f788a20ec974..bec42ecf9988 100644
--- a/sys/i386/linux/linux_sysvec.c
+++ b/sys/i386/linux/linux_sysvec.c
@@ -784,7 +784,6 @@ linux_fetch_syscall_args(struct thread *td)
 		sa->callp = &p->p_sysent->sv_table[p->p_sysent->sv_size - 1];
 	else
 		sa->callp = &p->p_sysent->sv_table[sa->code];
-	sa->narg = sa->callp->sy_narg;
 
 	td->td_retval[0] = 0;
 	td->td_retval[1] = frame->tf_edx;
diff --git a/sys/kern/kern_thread.c b/sys/kern/kern_thread.c
index 37120a06d1e2..a97631a8242b 100644
--- a/sys/kern/kern_thread.c
+++ b/sys/kern/kern_thread.c
@@ -82,7 +82,7 @@ _Static_assert(offsetof(struct thread, td_flags) == 0xfc,
     "struct thread KBI td_flags");
 _Static_assert(offsetof(struct thread, td_pflags) == 0x104,
     "struct thread KBI td_pflags");
-_Static_assert(offsetof(struct thread, td_frame) == 0x4a8,
+_Static_assert(offsetof(struct thread, td_frame) == 0x4a0,
     "struct thread KBI td_frame");
 _Static_assert(offsetof(struct thread, td_emuldata) == 0x6b0,
     "struct thread KBI td_emuldata");
@@ -102,9 +102,9 @@ _Static_assert(offsetof(struct thread, td_flags) == 0x98,
     "struct thread KBI td_flags");
 _Static_assert(offsetof(struct thread, td_pflags) == 0xa0,
     "struct thread KBI td_pflags");
-_Static_assert(offsetof(struct thread, td_frame) == 0x304,
+_Static_assert(offsetof(struct thread, td_frame) == 0x300,
     "struct thread KBI td_frame");
-_Static_assert(offsetof(struct thread, td_emuldata) == 0x348,
+_Static_assert(offsetof(struct thread, td_emuldata) == 0x344,
     "struct thread KBI td_emuldata");
 _Static_assert(offsetof(struct proc, p_flag) == 0x68,
     "struct proc KBI p_flag");
diff --git a/sys/kern/subr_syscall.c b/sys/kern/subr_syscall.c
index cfd3496e81b2..1fcb038bba07 100644
--- a/sys/kern/subr_syscall.c
+++ b/sys/kern/subr_syscall.c
@@ -79,7 +79,7 @@ syscallenter(struct thread *td)
 	error = (p->p_sysent->sv_fetch_syscall_args)(td);
 #ifdef KTRACE
 	if (KTRPOINT(td, KTR_SYSCALL))
-		ktrsyscall(sa->code, sa->narg, sa->args);
+		ktrsyscall(sa->code, sa->callp->sy_narg, sa->args);
 #endif
 	KTR_START4(KTR_SYSC, "syscall", syscallname(p, sa->code),
 	    (uintptr_t)td, "pid:%d", td->td_proc->p_pid, "arg0:%p", sa->args[0],
@@ -104,7 +104,7 @@ syscallenter(struct thread *td)
 		error = (p->p_sysent->sv_fetch_syscall_args)(td);
 #ifdef KTRACE
 		if (KTRPOINT(td, KTR_SYSCALL))
-			ktrsyscall(sa->code, sa->narg, sa->args);
+			ktrsyscall(sa->code, sa->callp->sy_narg, sa->args);
 #endif
 		if (error != 0) {
 			td->td_errno = error;
diff --git a/sys/kern/sys_process.c b/sys/kern/sys_process.c
index ca3eb046b6f1..3a184f1d678f 100644
--- a/sys/kern/sys_process.c
+++ b/sys/kern/sys_process.c
@@ -925,7 +925,7 @@ kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data)
 			break;
 		}
 		bzero(addr, sizeof(td2->td_sa.args));
-		bcopy(td2->td_sa.args, addr, td2->td_sa.narg *
+		bcopy(td2->td_sa.args, addr, td2->td_sa.callp->sy_narg *
 		    sizeof(register_t));
 		break;
 
@@ -1246,7 +1246,7 @@ kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data)
 		strcpy(pl->pl_tdname, td2->td_name);
 		if ((td2->td_dbgflags & (TDB_SCE | TDB_SCX)) != 0) {
 			pl->pl_syscall_code = td2->td_sa.code;
-			pl->pl_syscall_narg = td2->td_sa.narg;
+			pl->pl_syscall_narg = td2->td_sa.callp->sy_narg;
 		} else {
 			pl->pl_syscall_code = 0;
 			pl->pl_syscall_narg = 0;
diff --git a/sys/mips/include/proc.h b/sys/mips/include/proc.h
index 696854f40992..d0acf5e46c76 100644
--- a/sys/mips/include/proc.h
+++ b/sys/mips/include/proc.h
@@ -85,7 +85,6 @@ struct syscall_args {
 	u_int code;
 	struct sysent *callp;
 	register_t args[8];
-	int narg;
 	struct trapframe *trapframe;
 };
 
diff --git a/sys/mips/mips/trap.c b/sys/mips/mips/trap.c
index fcd0214e0d3e..0fdd8f77c502 100644
--- a/sys/mips/mips/trap.c
+++ b/sys/mips/mips/trap.c
@@ -448,9 +448,7 @@ cpu_fetch_syscall_args(struct thread *td)
 	else
 		sa->callp = &se->sv_table[sa->code];
 
-	sa->narg = sa->callp->sy_narg;
-
-	if (sa->narg > nsaved) {
+	if (sa->callp->sy_narg > nsaved) {
 #if defined(__mips_n32) || defined(__mips_n64)
 		/*
 		 * XXX
@@ -462,7 +460,7 @@ cpu_fetch_syscall_args(struct thread *td)
 		if (!SV_PROC_FLAG(td->td_proc, SV_ILP32))
 #endif
 			printf("SYSCALL #%u pid:%u, narg (%u) > nsaved (%u).\n",
-			    sa->code, td->td_proc->p_pid, sa->narg, nsaved);
+			    sa->code, td->td_proc->p_pid, sa->callp->sy_narg, nsaved);
 #endif
 #if (defined(__mips_n32) || defined(__mips_n64)) && defined(COMPAT_FREEBSD32)
 		if (SV_PROC_FLAG(td->td_proc, SV_ILP32)) {
@@ -470,7 +468,7 @@ cpu_fetch_syscall_args(struct thread *td)
 			int32_t arg;
 
 			error = 0; /* XXX GCC is awful.  */
-			for (i = nsaved; i < sa->narg; i++) {
+			for (i = nsaved; i < sa->callp->sy_narg; i++) {
 				error = copyin((caddr_t)(intptr_t)(locr0->sp +
 				    (4 + (i - nsaved)) * sizeof(int32_t)),
 				    (caddr_t)&arg, sizeof arg);
@@ -482,7 +480,7 @@ cpu_fetch_syscall_args(struct thread *td)
 #endif
 		error = copyin((caddr_t)(intptr_t)(locr0->sp +
 		    4 * sizeof(register_t)), (caddr_t)&sa->args[nsaved],
-		   (u_int)(sa->narg - nsaved) * sizeof(register_t));
+		   (u_int)(sa->callp->sy_narg - nsaved) * sizeof(register_t));
 		if (error != 0) {
 			locr0->v0 = error;
 			locr0->a3 = 1;
diff --git a/sys/powerpc/include/proc.h b/sys/powerpc/include/proc.h
index de739cf7d273..47605505b48a 100644
--- a/sys/powerpc/include/proc.h
+++ b/sys/powerpc/include/proc.h
@@ -63,7 +63,6 @@ struct syscall_args {
 	u_int code;
 	struct sysent *callp;
 	register_t args[10];
-	int narg;
 };
 
 #ifdef _KERNEL
diff --git a/sys/powerpc/powerpc/trap.c b/sys/powerpc/powerpc/trap.c
index ceb6e5be9830..1bc3b6a0c550 100644
--- a/sys/powerpc/powerpc/trap.c
+++ b/sys/powerpc/powerpc/trap.c
@@ -639,7 +639,7 @@ cpu_fetch_syscall_args(struct thread *td)
 	struct syscall_args *sa;
 	caddr_t	params;
 	size_t argsz;
-	int error, n, i;
+	int error, n, narg, i;
 
 	p = td->td_proc;
 	frame = td->td_frame;
@@ -680,7 +680,7 @@ cpu_fetch_syscall_args(struct thread *td)
 	else
 		sa->callp = &p->p_sysent->sv_table[sa->code];
 
-	sa->narg = sa->callp->sy_narg;
+	narg = sa->callp->sy_narg;
 
 	if (SV_PROC_FLAG(p, SV_ILP32)) {
 		argsz = sizeof(uint32_t);
@@ -695,17 +695,17 @@ cpu_fetch_syscall_args(struct thread *td)
 			sa->args[i] = ((u_register_t *)(params))[i];
 	}
 
-	if (sa->narg > n)
+	if (narg > n)
 		error = copyin(MOREARGS(frame->fixreg[1]), sa->args + n,
-			       (sa->narg - n) * argsz);
+			       (narg - n) * argsz);
 	else
 		error = 0;
 
 #ifdef __powerpc64__
-	if (SV_PROC_FLAG(p, SV_ILP32) && sa->narg > n) {
+	if (SV_PROC_FLAG(p, SV_ILP32) && narg > n) {
 		/* Expand the size of arguments copied from the stack */
 
-		for (i = sa->narg; i >= n; i--)
+		for (i = narg; i >= n; i--)
 			sa->args[i] = ((uint32_t *)(&sa->args[n]))[i-n];
 	}
 #endif
diff --git a/sys/riscv/include/proc.h b/sys/riscv/include/proc.h
index 644bb91c4ad6..4b5ae9ebe3ed 100644
--- a/sys/riscv/include/proc.h
+++ b/sys/riscv/include/proc.h
@@ -50,7 +50,6 @@ struct syscall_args {
 	u_int code;
 	struct sysent *callp;
 	register_t args[MAXARGS];
-	int narg;
 };
 
 #endif /* !_MACHINE_PROC_H_ */
diff --git a/sys/riscv/riscv/trap.c b/sys/riscv/riscv/trap.c
index 1f59e4c53711..0992d1ca361a 100644
--- a/sys/riscv/riscv/trap.c
+++ b/sys/riscv/riscv/trap.c
@@ -117,9 +117,8 @@ cpu_fetch_syscall_args(struct thread *td)
 	else
 		sa->callp = &p->p_sysent->sv_table[sa->code];
 
-	sa->narg = sa->callp->sy_narg;
 	memcpy(sa->args, ap, nap * sizeof(register_t));
-	if (sa->narg > nap)
+	if (sa->callp->sy_narg > nap)
 		panic("TODO: Could we have more then %d args?", NARGREG);
 
 	td->td_retval[0] = 0;