diff --git a/ObsoleteFiles.inc b/ObsoleteFiles.inc
index 5f0067243f1e..872781642672 100644
--- a/ObsoleteFiles.inc
+++ b/ObsoleteFiles.inc
@@ -36,6 +36,9 @@
 #   xargs -n1 | sort | uniq -d;
 # done
 
+# 20200401: Remove procfs-based process debugging
+OLD_FILES+=usr/include/sys/pioctl.h
+
 # 20200330: GDB_LIBEXEC option retired (always true)
 OLD_FILES+=usr/bin/gdb
 OLD_FILES+=usr/bin/gdbserver
diff --git a/lib/libsysdecode/Makefile b/lib/libsysdecode/Makefile
index b13c0f5770d5..d58858086bc9 100644
--- a/lib/libsysdecode/Makefile
+++ b/lib/libsysdecode/Makefile
@@ -119,11 +119,6 @@ CFLAGS+=-DPF
 # Workaround duplicate declarations in <netinet/ip_compat.h>
 CFLAGS.gcc.ioctl.c+= -Wno-redundant-decls
 
-# Ignore deprecation warning in <sys/pioctl.h>
-CFLAGS.clang.ioctl.c+= -Wno-\#warnings
-CFLAGS.gcc.ioctl.c+= -Wno-cpp
-
-CFLAGS.clang+=	${CFLAGS.clang.${.IMPSRC}}
 CFLAGS.gcc+=	${CFLAGS.gcc.${.IMPSRC}}
 
 DEPENDOBJS+=	tables.h
diff --git a/sys/amd64/amd64/trap.c b/sys/amd64/amd64/trap.c
index ecd2edc94a80..216cf15b0bf9 100644
--- a/sys/amd64/amd64/trap.c
+++ b/sys/amd64/amd64/trap.c
@@ -57,7 +57,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/bus.h>
 #include <sys/systm.h>
 #include <sys/proc.h>
-#include <sys/pioctl.h>
 #include <sys/ptrace.h>
 #include <sys/kdb.h>
 #include <sys/kernel.h>
diff --git a/sys/amd64/amd64/vm_machdep.c b/sys/amd64/amd64/vm_machdep.c
index 60a252e0d6c1..37a71c9d58b6 100644
--- a/sys/amd64/amd64/vm_machdep.c
+++ b/sys/amd64/amd64/vm_machdep.c
@@ -58,7 +58,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/malloc.h>
 #include <sys/mbuf.h>
 #include <sys/mutex.h>
-#include <sys/pioctl.h>
 #include <sys/priv.h>
 #include <sys/proc.h>
 #include <sys/procctl.h>
@@ -198,15 +197,11 @@ cpu_fork(struct thread *td1, struct proc *p2, struct thread *td2, int flags)
 	td2->td_frame->tf_rdx = 1;
 
 	/*
-	 * If the parent process has the trap bit set (i.e. a debugger had
-	 * single stepped the process to the system call), we need to clear
-	 * the trap flag from the new frame unless the debugger had set PF_FORK
-	 * on the parent.  Otherwise, the child will receive a (likely
-	 * unexpected) SIGTRAP when it executes the first instruction after
-	 * returning  to userland.
+	 * If the parent process has the trap bit set (i.e. a debugger
+	 * had single stepped the process to the system call), we need
+	 * to clear the trap flag from the new frame.
 	 */
-	if ((p1->p_pfsflags & PF_FORK) == 0)
-		td2->td_frame->tf_rflags &= ~PSL_T;
+	td2->td_frame->tf_rflags &= ~PSL_T;
 
 	/*
 	 * Set registers for trampoline to user mode.  Leave space for the
diff --git a/sys/amd64/ia32/ia32_reg.c b/sys/amd64/ia32/ia32_reg.c
index 4a068b7f61e2..b4ad5833abc5 100644
--- a/sys/amd64/ia32/ia32_reg.c
+++ b/sys/amd64/ia32/ia32_reg.c
@@ -41,7 +41,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/mutex.h>
 #include <sys/mman.h>
 #include <sys/namei.h>
-#include <sys/pioctl.h>
 #include <sys/proc.h>
 #include <sys/procfs.h>
 #include <sys/resourcevar.h>
diff --git a/sys/amd64/ia32/ia32_signal.c b/sys/amd64/ia32/ia32_signal.c
index 4e32434797a1..0f2d874d142e 100644
--- a/sys/amd64/ia32/ia32_signal.c
+++ b/sys/amd64/ia32/ia32_signal.c
@@ -46,7 +46,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/mutex.h>
 #include <sys/mman.h>
 #include <sys/namei.h>
-#include <sys/pioctl.h>
 #include <sys/proc.h>
 #include <sys/procfs.h>
 #include <sys/resourcevar.h>
diff --git a/sys/amd64/ia32/ia32_syscall.c b/sys/amd64/ia32/ia32_syscall.c
index 1bce6ad26513..4d08cfb43b63 100644
--- a/sys/amd64/ia32/ia32_syscall.c
+++ b/sys/amd64/ia32/ia32_syscall.c
@@ -52,7 +52,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/bus.h>
 #include <sys/systm.h>
 #include <sys/proc.h>
-#include <sys/pioctl.h>
 #include <sys/kernel.h>
 #include <sys/ktr.h>
 #include <sys/lock.h>
diff --git a/sys/arm/arm/syscall.c b/sys/arm/arm/syscall.c
index 2500404d01f5..37824b7e1742 100644
--- a/sys/arm/arm/syscall.c
+++ b/sys/arm/arm/syscall.c
@@ -92,7 +92,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/sysent.h>
 #include <sys/signalvar.h>
 #include <sys/ptrace.h>
-#include <sys/pioctl.h>
 
 #include <machine/frame.h>
 
diff --git a/sys/arm64/arm64/trap.c b/sys/arm64/arm64/trap.c
index 629f9114cc04..9391e8ee0698 100644
--- a/sys/arm64/arm64/trap.c
+++ b/sys/arm64/arm64/trap.c
@@ -34,7 +34,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/ktr.h>
 #include <sys/lock.h>
 #include <sys/mutex.h>
-#include <sys/pioctl.h>
 #include <sys/proc.h>
 #include <sys/ptrace.h>
 #include <sys/syscall.h>
diff --git a/sys/compat/ia32/ia32_sysvec.c b/sys/compat/ia32/ia32_sysvec.c
index d78f6b45ba80..cceb2b38b84c 100644
--- a/sys/compat/ia32/ia32_sysvec.c
+++ b/sys/compat/ia32/ia32_sysvec.c
@@ -42,7 +42,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/mutex.h>
 #include <sys/mman.h>
 #include <sys/namei.h>
-#include <sys/pioctl.h>
 #include <sys/proc.h>
 #include <sys/procfs.h>
 #include <sys/resourcevar.h>
diff --git a/sys/conf/files b/sys/conf/files
index dd7e40c06edb..5dc45250a6f5 100644
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -3517,7 +3517,6 @@ fs/nullfs/null_vnops.c		optional nullfs
 fs/procfs/procfs.c		optional procfs
 fs/procfs/procfs_dbregs.c	optional procfs
 fs/procfs/procfs_fpregs.c	optional procfs
-fs/procfs/procfs_ioctl.c	optional procfs
 fs/procfs/procfs_map.c		optional procfs
 fs/procfs/procfs_mem.c		optional procfs
 fs/procfs/procfs_note.c		optional procfs
diff --git a/sys/fs/procfs/procfs.c b/sys/fs/procfs/procfs.c
index cfc4f5e8eb24..92208497231e 100644
--- a/sys/fs/procfs/procfs.c
+++ b/sys/fs/procfs/procfs.c
@@ -163,7 +163,6 @@ procfs_init(PFS_INIT_ARGS)
 {
 	struct pfs_node *root;
 	struct pfs_node *dir;
-	struct pfs_node *node;
 
 	root = pi->pi_root;
 
@@ -182,10 +181,8 @@ procfs_init(PFS_INIT_ARGS)
 	    procfs_attr_rw, procfs_candebug, NULL, PFS_RDWR | PFS_RAW);
 	pfs_create_file(dir, "map", procfs_doprocmap,
 	    NULL, procfs_notsystem, NULL, PFS_RD);
-	node = pfs_create_file(dir, "mem", procfs_doprocmem,
+	pfs_create_file(dir, "mem", procfs_doprocmem,
 	    procfs_attr_rw, procfs_candebug, NULL, PFS_RDWR | PFS_RAW);
-	node->pn_ioctl = procfs_ioctl;
-	node->pn_close = procfs_close;
 	pfs_create_file(dir, "note", procfs_doprocnote,
 	    procfs_attr_w, procfs_candebug, NULL, PFS_WR);
 	pfs_create_file(dir, "notepg", procfs_doprocnote,
diff --git a/sys/fs/procfs/procfs.h b/sys/fs/procfs/procfs.h
index bafcfab41aa0..6e6d3b0df079 100644
--- a/sys/fs/procfs/procfs.h
+++ b/sys/fs/procfs/procfs.h
@@ -53,8 +53,6 @@ int	 procfs_doprocregs(PFS_FILL_ARGS);
 int	 procfs_doprocrlimit(PFS_FILL_ARGS);
 int	 procfs_doprocstatus(PFS_FILL_ARGS);
 int	 procfs_doproctype(PFS_FILL_ARGS);
-int	 procfs_ioctl(PFS_IOCTL_ARGS);
-int	 procfs_close(PFS_CLOSE_ARGS);
 
 /* Attributes */
 int	 procfs_attr_w(PFS_ATTR_ARGS);
diff --git a/sys/fs/procfs/procfs_ioctl.c b/sys/fs/procfs/procfs_ioctl.c
deleted file mode 100644
index 1c35906c7292..000000000000
--- a/sys/fs/procfs/procfs_ioctl.c
+++ /dev/null
@@ -1,263 +0,0 @@
-/*-
- * SPDX-License-Identifier: BSD-3-Clause
- *
- * Copyright (c) 2001 Dag-Erling Coïdan Smørgrav
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer
- *    in this position and unchanged.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. The name of the author may not be used to endorse or promote products
- *    derived from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
- * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
- * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- *      $FreeBSD$
- */
-
-#include <sys/param.h>
-#include <sys/lock.h>
-#include <sys/mutex.h>
-#include <sys/pioctl.h>
-#include <sys/priv.h>
-#include <sys/proc.h>
-#include <sys/signalvar.h>
-#include <sys/systm.h>
-
-#include <fs/pseudofs/pseudofs.h>
-#include <fs/procfs/procfs.h>
-
-#ifdef COMPAT_FREEBSD32
-struct procfs_status32 {
-	int	state;	/* Running, stopped, something else? */
-	int	flags;	/* Any flags */
-	unsigned int	events;	/* Events to stop on */
-	int	why;	/* What event, if any, proc stopped on */
-	unsigned int	val;	/* Any extra data */
-};
-
-#define	PIOCWAIT32	_IOR('p', 4, struct procfs_status32)
-#define	PIOCSTATUS32	_IOR('p', 6, struct procfs_status32)
-#endif
-
-/*
- * Process ioctls
- */
-int
-procfs_ioctl(PFS_IOCTL_ARGS)
-{
-	struct procfs_status *ps;
-#ifdef COMPAT_FREEBSD32
-	struct procfs_status32 *ps32;
-#endif
-	int error, flags, sig;
-#ifdef COMPAT_FREEBSD6
-	int ival;
-#endif
-	static struct timeval lasttime;
-	static struct timeval interval = { .tv_sec = 1, .tv_usec = 0 };
-
-	KASSERT(p != NULL,
-	    ("%s() called without a process", __func__));
-	PROC_LOCK_ASSERT(p, MA_OWNED);
-
-	switch (cmd) {
-#if defined(COMPAT_FREEBSD5) || defined(COMPAT_FREEBSD4) || defined(COMPAT_43)
-	case _IOC(IOC_IN, 'p', 1, 0):
-#endif
-#ifdef COMPAT_FREEBSD6
-	case _IO('p', 1):
-#endif
-	case PIOCBIS:
-#if defined(COMPAT_FREEBSD5) || defined(COMPAT_FREEBSD4) || defined(COMPAT_43)
-	case _IOC(IOC_IN, 'p', 2, 0):
-#endif
-#ifdef COMPAT_FREEBSD6
-	case _IO('p', 2):
-#endif
-	case PIOCBIC:
-#if defined(COMPAT_FREEBSD5) || defined(COMPAT_FREEBSD4) || defined(COMPAT_43)
-	case _IOC(IOC_IN, 'p', 3, 0):
-#endif
-#ifdef COMPAT_FREEBSD6
-	case _IO('p', 3):
-#endif
-	case PIOCSFL:
-	case PIOCGFL:
-	case PIOCWAIT:
-	case PIOCSTATUS:
-#ifdef COMPAT_FREEBSD32
-	case PIOCWAIT32:
-	case PIOCSTATUS32:
-#endif
-#if defined(COMPAT_FREEBSD5) || defined(COMPAT_FREEBSD4) || defined(COMPAT_43)
-	case _IOC(IOC_IN, 'p', 5, 0):
-#endif
-#ifdef COMPAT_FREEBSD6
-	case _IO('p', 5):
-#endif
-	case PIOCCONT:
-		if (ratecheck(&lasttime, &interval) != 0)
-			gone_in(13, "procfs-based process debugging");
-		break;
-	}
-
-	error = 0;
-	switch (cmd) {
-#if defined(COMPAT_FREEBSD5) || defined(COMPAT_FREEBSD4) || defined(COMPAT_43)
-	case _IOC(IOC_IN, 'p', 1, 0):
-#endif
-#ifdef COMPAT_FREEBSD6
-	case _IO('p', 1):
-		ival = IOCPARM_IVAL(data);
-		data = &ival;
-#endif
-	case PIOCBIS:
-		p->p_stops |= *(unsigned int *)data;
-		break;
-#if defined(COMPAT_FREEBSD5) || defined(COMPAT_FREEBSD4) || defined(COMPAT_43)
-	case _IOC(IOC_IN, 'p', 2, 0):
-#endif
-#ifdef COMPAT_FREEBSD6
-	case _IO('p', 2):
-		ival = IOCPARM_IVAL(data);
-		data = &ival;
-#endif
-	case PIOCBIC:
-		p->p_stops &= ~*(unsigned int *)data;
-		break;
-#if defined(COMPAT_FREEBSD5) || defined(COMPAT_FREEBSD4) || defined(COMPAT_43)
-	case _IOC(IOC_IN, 'p', 3, 0):
-#endif
-#ifdef COMPAT_FREEBSD6
-	case _IO('p', 3):
-		ival = IOCPARM_IVAL(data);
-		data = &ival;
-#endif
-	case PIOCSFL:
-		flags = *(unsigned int *)data;
-		if (flags & PF_ISUGID) {
-			/*
-			 * XXXRW: Is this specific check required here, as
-			 * p_candebug() should implement it, or other checks
-			 * are missing.
-			 */
-			error = priv_check(td, PRIV_DEBUG_SUGID);
-			if (error)
-				break;
-		}
-		p->p_pfsflags = flags;
-		break;
-	case PIOCGFL:
-		*(unsigned int *)data = p->p_pfsflags;
-		break;
-	case PIOCWAIT:
-		while (p->p_step == 0 && (p->p_flag & P_WEXIT) == 0) {
-			/* sleep until p stops */
-			_PHOLD(p);
-			error = msleep(&p->p_stype, &p->p_mtx,
-			    PWAIT|PCATCH, "pioctl", 0);
-			_PRELE(p);
-			if (error != 0)
-				break;
-		}
-		/* fall through to PIOCSTATUS */
-	case PIOCSTATUS:
-		ps = (struct procfs_status *)data;
-		ps->state = (p->p_step == 0);
-		ps->flags = 0; /* nope */
-		ps->events = p->p_stops;
-		ps->why = p->p_step ? p->p_stype : 0;
-		ps->val = p->p_step ? p->p_xsig : 0;
-		break;
-#ifdef COMPAT_FREEBSD32
-	case PIOCWAIT32:
-		while (p->p_step == 0 && (p->p_flag & P_WEXIT) == 0) {
-			/* sleep until p stops */
-			_PHOLD(p);
-			error = msleep(&p->p_stype, &p->p_mtx,
-			    PWAIT|PCATCH, "pioctl", 0);
-			_PRELE(p);
-			if (error != 0)
-				break;
-		}
-		/* fall through to PIOCSTATUS32 */
-	case PIOCSTATUS32:
-		ps32 = (struct procfs_status32 *)data;
-		ps32->state = (p->p_step == 0);
-		ps32->flags = 0; /* nope */
-		ps32->events = p->p_stops;
-		ps32->why = p->p_step ? p->p_stype : 0;
-		ps32->val = p->p_step ? p->p_xsig : 0;
-		break;
-#endif
-#if defined(COMPAT_FREEBSD5) || defined(COMPAT_FREEBSD4) || defined(COMPAT_43)
-	case _IOC(IOC_IN, 'p', 5, 0):
-#endif
-#ifdef COMPAT_FREEBSD6
-	case _IO('p', 5):
-		ival = IOCPARM_IVAL(data);
-		data = &ival;
-#endif
-	case PIOCCONT:
-		if (p->p_step == 0)
-			break;
-		sig = *(unsigned int *)data;
-		if (sig != 0 && !_SIG_VALID(sig)) {
-			error = EINVAL;
-			break;
-		}
-#if 0
-		p->p_step = 0;
-		if (P_SHOULDSTOP(p)) {
-			p->p_xsig = sig;
-			p->p_flag &= ~(P_STOPPED_TRACE|P_STOPPED_SIG);
-			PROC_SLOCK(p);
-			thread_unsuspend(p);
-			PROC_SUNLOCK(p);
-		} else if (sig)
-			kern_psignal(p, sig);
-#else
-		if (sig)
-			kern_psignal(p, sig);
-		p->p_step = 0;
-		wakeup(&p->p_step);
-#endif
-		break;
-	default:
-		error = (ENOTTY);
-	}
-
-	return (error);
-}
-
-/*
- * Clean up on last close
- */
-int
-procfs_close(PFS_CLOSE_ARGS)
-{
-	if (p != NULL && (p->p_pfsflags & PF_LINGER) == 0) {
-		PROC_LOCK_ASSERT(p, MA_OWNED);
-		p->p_pfsflags = 0;
-		p->p_stops = 0;
-		p->p_step = 0;
-		wakeup(&p->p_step);
-	}
-	return (0);
-}
diff --git a/sys/i386/i386/trap.c b/sys/i386/i386/trap.c
index 54b28b80ef7f..ccf16bf009cd 100644
--- a/sys/i386/i386/trap.c
+++ b/sys/i386/i386/trap.c
@@ -58,7 +58,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/bus.h>
 #include <sys/systm.h>
 #include <sys/proc.h>
-#include <sys/pioctl.h>
 #include <sys/ptrace.h>
 #include <sys/kdb.h>
 #include <sys/kernel.h>
diff --git a/sys/i386/i386/vm_machdep.c b/sys/i386/i386/vm_machdep.c
index 62c7a6248641..a25c33b34d34 100644
--- a/sys/i386/i386/vm_machdep.c
+++ b/sys/i386/i386/vm_machdep.c
@@ -60,7 +60,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/malloc.h>
 #include <sys/mbuf.h>
 #include <sys/mutex.h>
-#include <sys/pioctl.h>
 #include <sys/proc.h>
 #include <sys/sysent.h>
 #include <sys/sf_buf.h>
@@ -208,15 +207,11 @@ cpu_fork(struct thread *td1, struct proc *p2, struct thread *td2, int flags)
 	td2->td_frame->tf_edx = 1;
 
 	/*
-	 * If the parent process has the trap bit set (i.e. a debugger had
-	 * single stepped the process to the system call), we need to clear
-	 * the trap flag from the new frame unless the debugger had set PF_FORK
-	 * on the parent.  Otherwise, the child will receive a (likely
-	 * unexpected) SIGTRAP when it executes the first instruction after
-	 * returning  to userland.
+	 * If the parent process has the trap bit set (i.e. a debugger
+	 * had single stepped the process to the system call), we need
+	 * to clear the trap flag from the new frame.
 	 */
-	if ((p1->p_pfsflags & PF_FORK) == 0)
-		td2->td_frame->tf_eflags &= ~PSL_T;
+	td2->td_frame->tf_eflags &= ~PSL_T;
 
 	/*
 	 * Set registers for trampoline to user mode.  Leave space for the
diff --git a/sys/kern/imgact_elf.c b/sys/kern/imgact_elf.c
index 5ba9f7e083de..bbd5fcd5249e 100644
--- a/sys/kern/imgact_elf.c
+++ b/sys/kern/imgact_elf.c
@@ -50,7 +50,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/mount.h>
 #include <sys/mman.h>
 #include <sys/namei.h>
-#include <sys/pioctl.h>
 #include <sys/proc.h>
 #include <sys/procfs.h>
 #include <sys/ptrace.h>
diff --git a/sys/kern/kern_exec.c b/sys/kern/kern_exec.c
index 86ad8a8c9bbc..1e8cd39192fc 100644
--- a/sys/kern/kern_exec.c
+++ b/sys/kern/kern_exec.c
@@ -51,7 +51,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/mount.h>
 #include <sys/mutex.h>
 #include <sys/namei.h>
-#include <sys/pioctl.h>
 #include <sys/priv.h>
 #include <sys/proc.h>
 #include <sys/ptrace.h>
@@ -912,12 +911,6 @@ do_execve(struct thread *td, struct image_args *args, struct mac *mac_p)
 				td->td_dbgflags |= TDB_EXEC;
 			PROC_UNLOCK(p);
 		}
-
-		/*
-		 * Stop the process here if its stop event mask has
-		 * the S_EXEC bit set.
-		 */
-		STOPEVENT(p, S_EXEC, 0);
 	} else {
 exec_fail:
 		/* we're done here, clear P_INEXEC */
diff --git a/sys/kern/kern_exit.c b/sys/kern/kern_exit.c
index d3adc9604ab4..244e1a2111ba 100644
--- a/sys/kern/kern_exit.c
+++ b/sys/kern/kern_exit.c
@@ -53,7 +53,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/mutex.h>
 #include <sys/proc.h>
 #include <sys/procdesc.h>
-#include <sys/pioctl.h>
 #include <sys/jail.h>
 #include <sys/tty.h>
 #include <sys/wait.h>
@@ -280,15 +279,6 @@ exit1(struct thread *td, int rval, int signo)
 	p->p_xexit = rval;
 	p->p_xsig = signo;
 
-	/*
-	 * Wakeup anyone in procfs' PIOCWAIT.  They should have a hold
-	 * on our vmspace, so we should block below until they have
-	 * released their reference to us.  Note that if they have
-	 * requested S_EXIT stops we will block here until they ack
-	 * via PIOCCONT.
-	 */
-	_STOPEVENT(p, S_EXIT, 0);
-
 	/*
 	 * Ignore any pending request to stop due to a stop signal.
 	 * Once P_WEXIT is set, future requests will be ignored as
@@ -297,13 +287,8 @@ exit1(struct thread *td, int rval, int signo)
 	p->p_flag &= ~P_STOPPED_SIG;
 	KASSERT(!P_SHOULDSTOP(p), ("exiting process is stopped"));
 
-	/*
-	 * Note that we are exiting and do another wakeup of anyone in
-	 * PIOCWAIT in case they aren't listening for S_EXIT stops or
-	 * decided to wait again after we told them we are exiting.
-	 */
+	/* Note that we are exiting. */
 	p->p_flag |= P_WEXIT;
-	wakeup(&p->p_stype);
 
 	/*
 	 * Wait for any processes that have a hold on our vmspace to
diff --git a/sys/kern/kern_fork.c b/sys/kern/kern_fork.c
index d4c481b8f038..f94b7d31791b 100644
--- a/sys/kern/kern_fork.c
+++ b/sys/kern/kern_fork.c
@@ -59,7 +59,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/priv.h>
 #include <sys/proc.h>
 #include <sys/procdesc.h>
-#include <sys/pioctl.h>
 #include <sys/ptrace.h>
 #include <sys/racct.h>
 #include <sys/resourcevar.h>
@@ -582,15 +581,6 @@ do_fork(struct thread *td, struct fork_req *fr, struct proc *p2, struct thread *
 
 	callout_init_mtx(&p2->p_itcallout, &p2->p_mtx, 0);
 
-	/*
-	 * If PF_FORK is set, the child process inherits the
-	 * procfs ioctl flags from its parent.
-	 */
-	if (p1->p_pfsflags & PF_FORK) {
-		p2->p_stops = p1->p_stops;
-		p2->p_pfsflags = p1->p_pfsflags;
-	}
-
 	/*
 	 * This begins the section where we must prevent the parent
 	 * from being swapped.
@@ -1111,7 +1101,6 @@ fork_return(struct thread *td, struct trapframe *frame)
 		 */
 		PROC_LOCK(p);
 		td->td_dbgflags |= TDB_SCX;
-		_STOPEVENT(p, S_SCX, td->td_sa.code);
 		if ((p->p_ptevents & PTRACE_SCX) != 0 ||
 		    (td->td_dbgflags & TDB_BORN) != 0)
 			ptracestop(td, SIGTRAP, NULL);
diff --git a/sys/kern/kern_prot.c b/sys/kern/kern_prot.c
index bd26317599d8..a3e7b162e100 100644
--- a/sys/kern/kern_prot.c
+++ b/sys/kern/kern_prot.c
@@ -65,7 +65,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/sysent.h>
 #include <sys/sysproto.h>
 #include <sys/jail.h>
-#include <sys/pioctl.h>
 #include <sys/racct.h>
 #include <sys/rctl.h>
 #include <sys/resourcevar.h>
@@ -2192,8 +2191,6 @@ setsugid(struct proc *p)
 
 	PROC_LOCK_ASSERT(p, MA_OWNED);
 	p->p_flag |= P_SUGID;
-	if (!(p->p_pfsflags & PF_ISUGID))
-		p->p_stops = 0;
 }
 
 /*-
diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c
index 0d597e559c8d..d36c382d3e23 100644
--- a/sys/kern/kern_sig.c
+++ b/sys/kern/kern_sig.c
@@ -67,7 +67,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/procdesc.h>
 #include <sys/ptrace.h>
 #include <sys/posix4.h>
-#include <sys/pioctl.h>
 #include <sys/racct.h>
 #include <sys/resourcevar.h>
 #include <sys/sdt.h>
@@ -2256,14 +2255,6 @@ tdsendsignal(struct proc *p, struct thread *td, int sig, ksiginfo_t *ksi)
 	    !((prop & SIGPROP_CONT) && (p->p_flag & P_STOPPED_SIG)))
 		return (ret);
 
-	/* SIGKILL: Remove procfs STOPEVENTs. */
-	if (sig == SIGKILL) {
-		/* from procfs_ioctl.c: PIOCBIC */
-		p->p_stops = 0;
-		/* from procfs_ioctl.c: PIOCCONT */
-		p->p_step = 0;
-		wakeup(&p->p_step);
-	}
 	wakeup_swapper = 0;
 
 	/*
@@ -2853,15 +2844,13 @@ issignal(struct thread *td)
 	struct sigqueue *queue;
 	sigset_t sigpending;
 	ksiginfo_t ksi;
-	int prop, sig, traced;
+	int prop, sig;
 
 	p = td->td_proc;
 	ps = p->p_sigacts;
 	mtx_assert(&ps->ps_mtx, MA_OWNED);
 	PROC_LOCK_ASSERT(p, MA_OWNED);
 	for (;;) {
-		traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
-
 		sigpending = td->td_sigqueue.sq_signals;
 		SIGSETOR(sigpending, p->p_sigqueue.sq_signals);
 		SIGSETNAND(sigpending, td->td_sigmask);
@@ -2904,17 +2893,12 @@ issignal(struct thread *td)
 			sig = sig_ffs(&sigpending);
 		}
 
-		if (p->p_stops & S_SIG) {
-			mtx_unlock(&ps->ps_mtx);
-			stopevent(p, S_SIG, sig);
-			mtx_lock(&ps->ps_mtx);
-		}
-
 		/*
 		 * We should see pending but ignored signals
 		 * only if P_TRACED was on when they were posted.
 		 */
-		if (SIGISMEMBER(ps->ps_sigignore, sig) && (traced == 0)) {
+		if (SIGISMEMBER(ps->ps_sigignore, sig) &&
+		    (p->p_flag & P_TRACED) == 0) {
 			sigqueue_delete(&td->td_sigqueue, sig);
 			sigqueue_delete(&p->p_sigqueue, sig);
 			continue;
@@ -3114,11 +3098,6 @@ postsig(int sig)
 		ktrpsig(sig, action, td->td_pflags & TDP_OLDMASK ?
 		    &td->td_oldsigmask : &td->td_sigmask, ksi.ksi_code);
 #endif
-	if ((p->p_stops & S_SIG) != 0) {
-		mtx_unlock(&ps->ps_mtx);
-		stopevent(p, S_SIG, sig);
-		mtx_lock(&ps->ps_mtx);
-	}
 
 	if (action == SIG_DFL) {
 		/*
@@ -3665,7 +3644,6 @@ coredump(struct thread *td)
 
 	PROC_LOCK_ASSERT(p, MA_OWNED);
 	MPASS((p->p_flag & P_HADTHREADS) == 0 || p->p_singlethread == td);
-	_STOPEVENT(p, S_CORE, 0);
 
 	if (!do_coredump || (!sugid_coredump && (p->p_flag & P_SUGID) != 0) ||
 	    (p->p_flag2 & P2_NOTRACE) != 0) {
diff --git a/sys/kern/kern_thread.c b/sys/kern/kern_thread.c
index 2169c4b2697e..56fb31f4dada 100644
--- a/sys/kern/kern_thread.c
+++ b/sys/kern/kern_thread.c
@@ -90,11 +90,11 @@ _Static_assert(offsetof(struct proc, p_flag) == 0xb0,
     "struct proc KBI p_flag");
 _Static_assert(offsetof(struct proc, p_pid) == 0xbc,
     "struct proc KBI p_pid");
-_Static_assert(offsetof(struct proc, p_filemon) == 0x3c8,
+_Static_assert(offsetof(struct proc, p_filemon) == 0x3c0,
     "struct proc KBI p_filemon");
-_Static_assert(offsetof(struct proc, p_comm) == 0x3e0,
+_Static_assert(offsetof(struct proc, p_comm) == 0x3d8,
     "struct proc KBI p_comm");
-_Static_assert(offsetof(struct proc, p_emuldata) == 0x4c0,
+_Static_assert(offsetof(struct proc, p_emuldata) == 0x4b8,
     "struct proc KBI p_emuldata");
 #endif
 #ifdef __i386__
@@ -110,11 +110,11 @@ _Static_assert(offsetof(struct proc, p_flag) == 0x68,
     "struct proc KBI p_flag");
 _Static_assert(offsetof(struct proc, p_pid) == 0x74,
     "struct proc KBI p_pid");
-_Static_assert(offsetof(struct proc, p_filemon) == 0x278,
+_Static_assert(offsetof(struct proc, p_filemon) == 0x26c,
     "struct proc KBI p_filemon");
-_Static_assert(offsetof(struct proc, p_comm) == 0x28c,
+_Static_assert(offsetof(struct proc, p_comm) == 0x280,
     "struct proc KBI p_comm");
-_Static_assert(offsetof(struct proc, p_emuldata) == 0x318,
+_Static_assert(offsetof(struct proc, p_emuldata) == 0x30c,
     "struct proc KBI p_emuldata");
 #endif
 
diff --git a/sys/kern/subr_syscall.c b/sys/kern/subr_syscall.c
index a67a0a28ba39..cfd3496e81b2 100644
--- a/sys/kern/subr_syscall.c
+++ b/sys/kern/subr_syscall.c
@@ -90,7 +90,6 @@ syscallenter(struct thread *td)
 		goto retval;
 	}
 
-	STOPEVENT(p, S_SCE, sa->narg);
 	if (__predict_false((p->p_flag & P_TRACED) != 0)) {
 		PROC_LOCK(p);
 		if (p->p_ptevents & PTRACE_SCE)
@@ -223,12 +222,6 @@ syscallret(struct thread *td)
 		td->td_dbgflags |= TDB_SCX;
 		PROC_UNLOCK(p);
 	}
-	/*
-	 * This works because errno is findable through the
-	 * register set.  If we ever support an emulation where this
-	 * is not the case, this code will need to be revisited.
-	 */
-	STOPEVENT(p, S_SCX, sa->code);
 	if (__predict_false(traced ||
 	    (td->td_dbgflags & (TDB_EXEC | TDB_FORK)) != 0)) {
 		PROC_LOCK(p);
diff --git a/sys/kern/subr_trap.c b/sys/kern/subr_trap.c
index b79d32dfda6d..08d8d2cb2239 100644
--- a/sys/kern/subr_trap.c
+++ b/sys/kern/subr_trap.c
@@ -59,7 +59,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/pmckern.h>
 #include <sys/proc.h>
 #include <sys/ktr.h>
-#include <sys/pioctl.h>
 #include <sys/ptrace.h>
 #include <sys/racct.h>
 #include <sys/resourcevar.h>
diff --git a/sys/kern/sys_process.c b/sys/kern/sys_process.c
index 09db10c9ced3..01583c7c97f9 100644
--- a/sys/kern/sys_process.c
+++ b/sys/kern/sys_process.c
@@ -43,7 +43,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/syscallsubr.h>
 #include <sys/sysent.h>
 #include <sys/sysproto.h>
-#include <sys/pioctl.h>
 #include <sys/priv.h>
 #include <sys/proc.h>
 #include <sys/vnode.h>
@@ -1524,26 +1523,3 @@ kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data)
 }
 #undef PROC_READ
 #undef PROC_WRITE
-
-/*
- * Stop a process because of a debugging event;
- * stay stopped until p->p_step is cleared
- * (cleared by PIOCCONT in procfs).
- */
-void
-stopevent(struct proc *p, unsigned int event, unsigned int val)
-{
-
-	PROC_LOCK_ASSERT(p, MA_OWNED);
-	p->p_step = 1;
-	CTR3(KTR_PTRACE, "stopevent: pid %d event %u val %u", p->p_pid, event,
-	    val);
-	do {
-		if (event != S_EXIT)
-			p->p_xsig = val;
-		p->p_xthread = NULL;
-		p->p_stype = event;	/* Which event caused the stop? */
-		wakeup(&p->p_stype);	/* Wake up any PIOCWAIT'ing procs */
-		msleep(&p->p_step, &p->p_mtx, PWAIT, "stopevent", 0);
-	} while (p->p_step);
-}
diff --git a/sys/mips/mips/trap.c b/sys/mips/mips/trap.c
index 2a5d67c36f91..ff8f51f67698 100644
--- a/sys/mips/mips/trap.c
+++ b/sys/mips/mips/trap.c
@@ -66,7 +66,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/user.h>
 #include <sys/buf.h>
 #include <sys/vnode.h>
-#include <sys/pioctl.h>
 #include <sys/sysctl.h>
 #include <sys/syslog.h>
 #include <sys/bus.h>
diff --git a/sys/modules/procfs/Makefile b/sys/modules/procfs/Makefile
index 5a819e2cae4b..282b200e5a60 100644
--- a/sys/modules/procfs/Makefile
+++ b/sys/modules/procfs/Makefile
@@ -7,7 +7,6 @@ SRCS=
 SRCS+=		vnode_if.h
 SRCS+=		procfs_dbregs.c
 SRCS+=		procfs_fpregs.c
-SRCS+=		procfs_ioctl.c
 SRCS+=		procfs_map.c
 SRCS+=		procfs_mem.c
 SRCS+=		procfs_note.c
diff --git a/sys/powerpc/powerpc/trap.c b/sys/powerpc/powerpc/trap.c
index 6529cdf76c88..7b5ed1aa45b3 100644
--- a/sys/powerpc/powerpc/trap.c
+++ b/sys/powerpc/powerpc/trap.c
@@ -40,7 +40,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/ktr.h>
 #include <sys/lock.h>
 #include <sys/mutex.h>
-#include <sys/pioctl.h>
 #include <sys/ptrace.h>
 #include <sys/reboot.h>
 #include <sys/syscall.h>
diff --git a/sys/riscv/riscv/trap.c b/sys/riscv/riscv/trap.c
index f6d547fe5f3f..e1d8bb76e2df 100644
--- a/sys/riscv/riscv/trap.c
+++ b/sys/riscv/riscv/trap.c
@@ -41,7 +41,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/ktr.h>
 #include <sys/lock.h>
 #include <sys/mutex.h>
-#include <sys/pioctl.h>
 #include <sys/bus.h>
 #include <sys/proc.h>
 #include <sys/ptrace.h>
diff --git a/sys/sys/param.h b/sys/sys/param.h
index 5c7a23ce7fa7..ec088bdbbd7e 100644
--- a/sys/sys/param.h
+++ b/sys/sys/param.h
@@ -60,7 +60,7 @@
  *		in the range 5 to 9.
  */
 #undef __FreeBSD_version
-#define __FreeBSD_version 1300087	/* Master, propagated to newvers */
+#define __FreeBSD_version 1300088	/* Master, propagated to newvers */
 
 /*
  * __FreeBSD_kernel__ indicates that this system uses the kernel of FreeBSD,
diff --git a/sys/sys/pioctl.h b/sys/sys/pioctl.h
deleted file mode 100644
index ed8a93a3be09..000000000000
--- a/sys/sys/pioctl.h
+++ /dev/null
@@ -1,85 +0,0 @@
-/*-
- * SPDX-License-Identifier: BSD-4-Clause
- *
- * Copyright 1997 Sean Eric Fagan
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- *    must display the following acknowledgement:
- *	This product includes software developed by Sean Eric Fagan
- * 4. Neither the name of the author may be used to endorse or promote
- *    products derived from this software without specific prior written
- *    permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- *
- */
-
-/*
- * procfs ioctl definitions.
- *
- * $FreeBSD$
- */
-
-#ifndef _SYS_PIOCTL_H
-# define _SYS_PIOCTL_H
-
-#ifndef _KERNEL
-#warning "<sys/pioctl.h> is deprecated, ptrace() should be used instead"
-#endif
-
-# include <sys/ioccom.h>
-
-struct procfs_status {
-	int	state;	/* Running, stopped, something else? */
-	int	flags;	/* Any flags */
-	unsigned long	events;	/* Events to stop on */
-	int	why;	/* What event, if any, proc stopped on */
-	unsigned long	val;	/* Any extra data */
-};
-
-# define	PIOCBIS	_IOWINT('p', 1)	/* Set event flag */
-# define	PIOCBIC	_IOWINT('p', 2)	/* Clear event flag */
-# define	PIOCSFL	_IOWINT('p', 3)	/* Set flags */
-			/* wait for proc to stop */
-# define	PIOCWAIT	_IOR('p', 4, struct procfs_status)
-# define	PIOCCONT	_IOWINT('p', 5)	/* Continue a process */
-			/* Get proc status */
-# define	PIOCSTATUS	_IOR('p', 6, struct procfs_status)
-# define	PIOCGFL	_IOR('p', 7, unsigned int)	/* Get flags */
-
-# define	S_EXEC	0x00000001	/* stop-on-exec */
-# define	S_SIG	0x00000002	/* stop-on-signal */
-# define	S_SCE	0x00000004	/* stop on syscall entry */
-# define	S_SCX	0x00000008	/* stop on syscall exit */
-# define	S_CORE	0x00000010	/* stop on coredump */
-# define	S_EXIT	0x00000020	/* stop on exit */
-# define	S_ALLSTOPS  0x003f	/* stop on all events */
-
-/*
- * If PF_LINGER is set in procp->p_pfsflags, then the last close
- * of a /proc/<pid>/mem file will not clear out the stops and continue
- * the process.
- */
-
-# define PF_LINGER	0x01	/* Keep stops around after last close */
-# define PF_ISUGID	0x02	/* Ignore UID/GID changes */
-# define PF_FORK	0x04	/* Retain settings on fork() */
-#endif 
diff --git a/sys/sys/proc.h b/sys/sys/proc.h
index bbae5cf1caae..48610210c95a 100644
--- a/sys/sys/proc.h
+++ b/sys/sys/proc.h
@@ -644,10 +644,6 @@ struct proc {
 	struct sigiolst	p_sigiolst;	/* (c) List of sigio sources. */
 	int		p_sigparent;	/* (c) Signal to parent on exit. */
 	int		p_sig;		/* (n) For core dump/debugger XXX. */
-	u_int		p_stops;	/* (c) Stop event bitmask. */
-	u_int		p_stype;	/* (c) Stop event type. */
-	char		p_step;		/* (c) Process is stopped. */
-	u_char		p_pfsflags;	/* (c) Procfs flags. */
 	u_int		p_ptevents;	/* (c + e) ptrace() event mask. */
 	struct nlminfo	*p_nlminfo;	/* (?) Only used by/for lockd. */
 	struct kaioinfo	*p_aioinfo;	/* (y) ASYNC I/O info. */
@@ -864,23 +860,6 @@ extern pid_t pid_max;
 #define	SESS_LEADER(p)	((p)->p_session->s_leader == (p))
 
 
-#define	STOPEVENT(p, e, v) do {						\
-	WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,			\
- 	    "checking stopevent %d", (e));				\
-	if ((p)->p_stops & (e))	{					\
-		PROC_LOCK(p);						\
-		stopevent((p), (e), (v));				\
-		PROC_UNLOCK(p);						\
-	}								\
-} while (0)
-#define	_STOPEVENT(p, e, v) do {					\
-	PROC_LOCK_ASSERT(p, MA_OWNED);					\
-	WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, &p->p_mtx.lock_object, \
- 	    "checking stopevent %d", (e));				\
-	if ((p)->p_stops & (e))						\
-		stopevent((p), (e), (v));				\
-} while (0)
-
 /* Lock and unlock a process. */
 #define	PROC_LOCK(p)	mtx_lock(&(p)->p_mtx)
 #define	PROC_TRYLOCK(p)	mtx_trylock(&(p)->p_mtx)