diff --git a/sys/kern/kern_ktrace.c b/sys/kern/kern_ktrace.c
--- a/sys/kern/kern_ktrace.c
+++ b/sys/kern/kern_ktrace.c
@@ -31,15 +31,16 @@
  * SUCH DAMAGE.
  */
 
-#include <sys/cdefs.h>
 #include "opt_ktrace.h"
 
-#include <sys/param.h>
-#include <sys/capsicum.h>
+#define	EXTERR_CATEGORY	EXTERR_KTRACE
 #include <sys/systm.h>
+#include <sys/capsicum.h>
+#include <sys/exterrvar.h>
 #include <sys/fcntl.h>
 #include <sys/kernel.h>
 #include <sys/kthread.h>
+#include <sys/ktrace.h>
 #include <sys/lock.h>
 #include <sys/mutex.h>
 #include <sys/malloc.h>
@@ -48,16 +49,15 @@
 #include <sys/priv.h>
 #include <sys/proc.h>
 #include <sys/resourcevar.h>
-#include <sys/unistd.h>
-#include <sys/vnode.h>
 #include <sys/socket.h>
 #include <sys/stat.h>
-#include <sys/ktrace.h>
 #include <sys/sx.h>
 #include <sys/sysctl.h>
 #include <sys/sysent.h>
 #include <sys/syslog.h>
 #include <sys/sysproto.h>
+#include <sys/unistd.h>
+#include <sys/vnode.h>
 
 #include <security/mac/mac_framework.h>
 
@@ -104,6 +104,7 @@
 		struct	ktr_fault ktr_fault;
 		struct	ktr_faultend ktr_faultend;
 		struct  ktr_struct_array ktr_struct_array;
+		struct	ktr_exterr ktr_exterr;
 	} ktr_data;
 	STAILQ_ENTRY(ktr_request) ktr_list;
 };
@@ -126,6 +127,7 @@
 	[KTR_STRUCT_ARRAY] = sizeof(struct ktr_struct_array),
 	[KTR_ARGS] = 0,
 	[KTR_ENVS] = 0,
+	[KTR_EXTERR] = sizeof(struct ktr_exterr),
 };
 
 static STAILQ_HEAD(, ktr_request) ktr_free;
@@ -1033,8 +1035,35 @@
 	ktr_enqueuerequest(td, req);
 	ktrace_exit(td);
 }
+
+void
+ktrexterr(struct thread *td)
+{
+	struct ktr_request *req;
+	struct ktr_exterr *ktre;
+
+	if (!KTRPOINT(td, KTR_EXTERR))
+		return;
+
+	req = ktr_getrequest(KTR_EXTERR);
+	if (req == NULL)
+		return;
+	ktre = &req->ktr_data.ktr_exterr;
+	if (exterr_to_ue(td, &ktre->ue) == 0)
+		ktr_enqueuerequest(td, req);
+	else
+		ktr_freerequest(req);
+	ktrace_exit(td);
+}
 #endif /* KTRACE */
 
+#ifndef KTRACE
+void
+ktrexterr(struct thread *td __unused)
+{
+}
+#endif
+
 /* Interface and common routines */
 
 #ifndef _SYS_SYSPROTO_H_
diff --git a/sys/kern/sys_generic.c b/sys/kern/sys_generic.c
--- a/sys/kern/sys_generic.c
+++ b/sys/kern/sys_generic.c
@@ -2202,6 +2202,23 @@
 	return (kcmp_cmp((uintptr_t)fp1->f_data, (uintptr_t)fp2->f_data));
 }
 
+int
+exterr_to_ue(struct thread *td, struct uexterror *ue)
+{
+	if ((td->td_pflags2 & TDP2_EXTERR) == 0)
+		return (ENOENT);
+
+	memset(ue, 0, sizeof(*ue));
+	ue->error = td->td_kexterr.error;
+	ue->cat = td->td_kexterr.cat;
+	ue->src_line = td->td_kexterr.src_line;
+	ue->p1 = td->td_kexterr.p1;
+	ue->p2 = td->td_kexterr.p2;
+	if (td->td_kexterr.msg != NULL)
+		strlcpy(ue->msg, td->td_kexterr.msg, sizeof(ue->msg));
+	return (0);
+}
+
 void
 exterr_copyout(struct thread *td)
 {
@@ -2215,18 +2232,11 @@
 
 	uloc = (char *)td->td_exterr_ptr + __offsetof(struct uexterror,
 	    error);
-	if ((td->td_pflags2 & TDP2_EXTERR) == 0) {
+	error = exterr_to_ue(td, &ue);
+	if (error != 0) {
 		ue.error = 0;
 		sz = sizeof(ue.error);
 	} else {
-		memset(&ue, 0, sizeof(ue));
-		ue.error = td->td_kexterr.error;
-		ue.cat = td->td_kexterr.cat;
-		ue.src_line = td->td_kexterr.src_line;
-		ue.p1 = td->td_kexterr.p1;
-		ue.p2 = td->td_kexterr.p2;
-		if (td->td_kexterr.msg != NULL)
-			strlcpy(ue.msg, td->td_kexterr.msg, sizeof(ue.msg));
 		sz = sizeof(ue) - __offsetof(struct uexterror, error);
 	}
 	error = copyout(&ue.error, uloc, sz);
diff --git a/sys/sys/_uexterror.h b/sys/sys/_uexterror.h
new file mode 100644
--- /dev/null
+++ b/sys/sys/_uexterror.h
@@ -0,0 +1,27 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2025 The FreeBSD Foundation
+ * All rights reserved.
+ *
+ * This software were developed by Konstantin Belousov <kib@FreeBSD.org>
+ * under sponsorship from the FreeBSD Foundation.
+ */
+
+#ifndef _SYS__UEXTERROR_H_
+#define	_SYS__UEXTERROR_H_
+
+#include <sys/_types.h>
+
+struct uexterror {
+	__uint32_t ver;
+	__uint32_t error;
+	__uint32_t cat;
+	__uint32_t src_line;
+	__uint64_t p1;
+	__uint64_t p2;
+	__uint64_t rsrv1[4];
+	char msg[128];
+};
+
+#endif
diff --git a/sys/sys/exterr_cat.h b/sys/sys/exterr_cat.h
--- a/sys/sys/exterr_cat.h
+++ b/sys/sys/exterr_cat.h
@@ -13,6 +13,8 @@
 
 #define	EXTERR_CAT_MMAP		1
 #define	EXTERR_CAT_FILEDESC	2
+#define	EXTERR_KTRACE		3	/* To allow inclusion of this
+					   file into kern_ktrace.c */
 
 #endif
 
diff --git a/sys/sys/exterrvar.h b/sys/sys/exterrvar.h
--- a/sys/sys/exterrvar.h
+++ b/sys/sys/exterrvar.h
@@ -12,19 +12,8 @@
 #define	_SYS_EXTERRVAR_H_
 
 #include <sys/_exterr.h>
+#include <sys/_uexterror.h>
 #include <sys/exterr_cat.h>
-#include <sys/types.h>
-
-struct uexterror {
-	uint32_t ver;
-	uint32_t error;
-	uint32_t cat;
-	uint32_t src_line;
-	uint64_t p1;
-	uint64_t p2;
-	uint64_t rsrv1[4];
-	char msg[128];
-};
 
 #define	UEXTERROR_MAXLEN	256
 
@@ -57,13 +46,19 @@
 		_Td->td_kexterr.p1 = (uintptr_t)pp1;		\
 		_Td->td_kexterr.p2 = (uintptr_t)pp2;		\
 		_Td->td_kexterr.src_line = __LINE__;		\
+		ktrexterr(_Td);					\
 	}							\
 } while (0)
 #define	SET_ERROR0(eerror, mmsg)	SET_ERROR2(eerror, mmsg, 0, 0)
 #define	SET_ERROR1(eerror, mmsg, pp1)	SET_ERROR2(eerror, mmsg, pp1, 0)
 
+int exterr_to_ue(struct thread *td, struct uexterror *ue);
+void ktrexterr(struct thread *td);
+
 #else	/* _KERNEL */
 
+#include <sys/types.h>
+
 __BEGIN_DECLS
 int exterrctl(u_int op, u_int flags, void *ptr);
 __END_DECLS
diff --git a/sys/sys/ktrace.h b/sys/sys/ktrace.h
--- a/sys/sys/ktrace.h
+++ b/sys/sys/ktrace.h
@@ -36,6 +36,7 @@
 #include <sys/caprights.h>
 #include <sys/signal.h>
 #include <sys/socket.h>
+#include <sys/_uexterror.h>
 #include <sys/_uio.h>
 
 /*
@@ -272,6 +273,14 @@
  */
 #define KTR_ENVS 17
 
+/*
+ * KTR_EXTERR - extended error reported
+ */
+#define	KTR_EXTERR 18
+struct ktr_exterr {
+	struct uexterror ue;
+};
+
 /*
  * KTR_DROP - If this bit is set in ktr_type, then at least one event
  * between the previous record and this record was dropped.
@@ -306,6 +315,7 @@
 #define	KTRFAC_STRUCT_ARRAY (1<<KTR_STRUCT_ARRAY)
 #define KTRFAC_ARGS     (1<<KTR_ARGS)
 #define KTRFAC_ENVS     (1<<KTR_ENVS)
+#define	KTRFAC_EXTERR	(1<<KTR_EXTERR)
 
 /*
  * trace flags (also in p_traceflags)
diff --git a/usr.bin/kdump/kdump.c b/usr.bin/kdump/kdump.c
--- a/usr.bin/kdump/kdump.c
+++ b/usr.bin/kdump/kdump.c
@@ -87,39 +87,40 @@
 #include <casper/cap_pwd.h>
 #endif
 
-int fetchprocinfo(struct ktr_header *, u_int *);
-u_int findabi(struct ktr_header *);
-int fread_tail(void *, int, int);
-void dumpheader(struct ktr_header *, u_int);
-void dumptimeval(struct ktr_header_v0 *kth);
-void dumptimespec(struct ktr_header *kth);
-void ktrsyscall(struct ktr_syscall *, u_int);
-void ktrsysret(struct ktr_sysret *, u_int);
-void ktrnamei(char *, int);
-void hexdump(char *, int, int);
-void visdump(char *, int, int);
-void ktrgenio(struct ktr_genio *, int);
-void ktrpsig(struct ktr_psig *);
-void ktrcsw(struct ktr_csw *);
-void ktrcsw_old(struct ktr_csw_old *);
-void ktruser(int, void *);
-void ktrcaprights(cap_rights_t *);
-void ktritimerval(struct itimerval *it);
-void ktrsockaddr(struct sockaddr *);
-void ktrsplice(struct splice *);
-void ktrstat(struct stat *);
-void ktrstruct(char *, size_t);
-void ktrcapfail(struct ktr_cap_fail *);
-void ktrfault(struct ktr_fault *);
-void ktrfaultend(struct ktr_faultend *);
-void ktrkevent(struct kevent *);
-void ktrpollfd(struct pollfd *);
-void ktrstructarray(struct ktr_struct_array *, size_t);
-void ktrbitset(char *, struct bitset *, size_t);
-void ktrsyscall_freebsd(struct ktr_syscall *ktr, register_t **resip,
+static int fetchprocinfo(struct ktr_header *, u_int *);
+static u_int findabi(struct ktr_header *);
+static int fread_tail(void *, int, int);
+static void dumpheader(struct ktr_header *, u_int);
+static void dumptimeval(struct ktr_header_v0 *kth);
+static void dumptimespec(struct ktr_header *kth);
+static void ktrsyscall(struct ktr_syscall *, u_int);
+static void ktrsysret(struct ktr_sysret *, u_int);
+static void ktrnamei(char *, int);
+static void hexdump(char *, int, int);
+static void visdump(char *, int, int);
+static void ktrgenio(struct ktr_genio *, int);
+static void ktrpsig(struct ktr_psig *);
+static void ktrcsw(struct ktr_csw *);
+static void ktrcsw_old(struct ktr_csw_old *);
+static void ktruser(int, void *);
+static void ktrcaprights(cap_rights_t *);
+static void ktritimerval(struct itimerval *it);
+static void ktrsockaddr(struct sockaddr *);
+static void ktrsplice(struct splice *);
+static void ktrstat(struct stat *);
+static void ktrstruct(char *, size_t);
+static void ktrcapfail(struct ktr_cap_fail *);
+static void ktrfault(struct ktr_fault *);
+static void ktrfaultend(struct ktr_faultend *);
+static void ktrkevent(struct kevent *);
+static void ktrpollfd(struct pollfd *);
+static void ktrstructarray(struct ktr_struct_array *, size_t);
+static void ktrbitset(char *, struct bitset *, size_t);
+static void ktrsyscall_freebsd(struct ktr_syscall *ktr, register_t **resip,
     int *resnarg, char *resc, u_int sv_flags);
-void ktrexecve(char *, int);
-void usage(void);
+static void ktrexecve(char *, int);
+static void ktrexterr(struct ktr_exterr *);
+static void usage(void);
 
 #define	TIMESTAMP_NONE		0x0
 #define	TIMESTAMP_ABSOLUTE	0x1
@@ -521,6 +522,8 @@
 		case KTR_ENVS:
 			ktrexecve(m, ktrlen);
 			break;
+		case KTR_EXTERR:
+			ktrexterr((struct ktr_exterr *)m);
 		default:
 			printf("\n");
 			break;
@@ -531,7 +534,7 @@
 	return 0;
 }
 
-int
+static int
 fread_tail(void *buf, int size, int num)
 {
 	int i;
@@ -543,7 +546,7 @@
 	return (i);
 }
 
-int
+static int
 fetchprocinfo(struct ktr_header *kth, u_int *flags)
 {
 	struct proc_info *pi;
@@ -578,7 +581,7 @@
 	return (0);
 }
 
-u_int
+static u_int
 findabi(struct ktr_header *kth)
 {
 	struct proc_info *pi;
@@ -591,7 +594,7 @@
 	return (0);
 }
 
-void
+static void
 dumptimeval(struct ktr_header_v0 *kth)
 {
 	static struct timeval prevtime, prevtime_e;
@@ -625,7 +628,7 @@
 	}
 }
 
-void
+static void
 dumptimespec(struct ktr_header *kth)
 {
 	static struct timespec prevtime, prevtime_e;
@@ -659,7 +662,26 @@
 	}
 }
 
-void
+static const char * const hdr_names[] = {
+	[KTR_SYSCALL] =		"CALL",
+	[KTR_SYSRET] =		"RET ",
+	[KTR_NAMEI] =		"NAMI",
+	[KTR_GENIO] =		"GIO ",
+	[KTR_PSIG] =		"PSIG",
+	[KTR_CSW] =		"CSW ",
+	[KTR_USER] =		"USER",
+	[KTR_STRUCT] =		"STRU",
+	[KTR_STRUCT_ARRAY] =	"STRU",
+	[KTR_SYSCTL] =		"SCTL",
+	[KTR_CAPFAIL] =		"CAP ",
+	[KTR_FAULT] =		"PFLT",
+	[KTR_FAULTEND] =	"PRET",
+	[KTR_ARGS] =		"ARGS",
+	[KTR_ENVS] =		"ENVS",
+	[KTR_EXTERR] =		"EERR",
+};
+
+static void
 dumpheader(struct ktr_header *kth, u_int sv_flags)
 {
 	static char unknown[64];
@@ -667,53 +689,12 @@
 	const char *arch;
 	const char *type;
 
-	switch (kth->ktr_type) {
-	case KTR_SYSCALL:
-		type = "CALL";
-		break;
-	case KTR_SYSRET:
-		type = "RET ";
-		break;
-	case KTR_NAMEI:
-		type = "NAMI";
-		break;
-	case KTR_GENIO:
-		type = "GIO ";
-		break;
-	case KTR_PSIG:
-		type = "PSIG";
-		break;
-	case KTR_CSW:
-		type = "CSW ";
-		break;
-	case KTR_USER:
-		type = "USER";
-		break;
-	case KTR_STRUCT:
-	case KTR_STRUCT_ARRAY:
-		type = "STRU";
-		break;
-	case KTR_SYSCTL:
-		type = "SCTL";
-		break;
-	case KTR_CAPFAIL:
-		type = "CAP ";
-		break;
-	case KTR_FAULT:
-		type = "PFLT";
-		break;
-	case KTR_FAULTEND:
-		type = "PRET";
-		break;
-	case KTR_ARGS:
-	        type = "ARGS";
-	        break;
-	case KTR_ENVS:
-	        type = "ENVS";
-	        break;
-	default:
-		sprintf(unknown, "UNKNOWN(%d)", kth->ktr_type);
+	if (kth->ktr_type < 0 || (size_t)kth->ktr_type >= nitems(hdr_names)) {
+		snprintf(unknown, sizeof(unknown), "UNKNOWN(%d)",
+		    kth->ktr_type);
 		type = unknown;
+	} else {
+		type = hdr_names[kth->ktr_type];
 	}
 
 	/*
@@ -826,7 +807,7 @@
 		printf("SIG %d", signo);
 }
 
-void
+static void
 ktrsyscall(struct ktr_syscall *ktr, u_int sv_flags)
 {
 	int narg = ktr->ktr_narg;
@@ -862,7 +843,7 @@
 	putchar('\n');
 }
 
-void
+static void
 ktrsyscall_freebsd(struct ktr_syscall *ktr, register_t **resip,
     int *resnarg, char *resc, u_int sv_flags)
 {
@@ -1619,7 +1600,7 @@
 	*resnarg = narg;
 }
 
-void
+static void
 ktrsysret(struct ktr_sysret *ktr, u_int sv_flags)
 {
 	register_t ret = ktr->ktr_retval;
@@ -1652,13 +1633,13 @@
 	putchar('\n');
 }
 
-void
+static void
 ktrnamei(char *cp, int len)
 {
 	printf("\"%.*s\"\n", len, cp);
 }
 
-void
+static void
 ktrexecve(char *m, int len)
 {
 	int i = 0;
@@ -1673,7 +1654,7 @@
 	printf("\n");
 }
 
-void
+static void
 hexdump(char *p, int len, int screenwidth)
 {
 	int n, i;
@@ -1719,7 +1700,7 @@
 		printf("\n");
 }
 
-void
+static void
 visdump(char *dp, int datalen, int screenwidth)
 {
 	int col = 0;
@@ -1765,7 +1746,7 @@
 	printf("\"\n");
 }
 
-void
+static void
 ktrgenio(struct ktr_genio *ktr, int len)
 {
 	int datalen = len - sizeof (struct ktr_genio);
@@ -1803,7 +1784,7 @@
 		visdump(dp, datalen, screenwidth);
 }
 
-void
+static void
 ktrpsig(struct ktr_psig *psig)
 {
 	const char *str;
@@ -1824,21 +1805,21 @@
 	putchar('\n');
 }
 
-void
+static void
 ktrcsw_old(struct ktr_csw_old *cs)
 {
 	printf("%s %s\n", cs->out ? "stop" : "resume",
 		cs->user ? "user" : "kernel");
 }
 
-void
+static void
 ktrcsw(struct ktr_csw *cs)
 {
 	printf("%s %s \"%s\"\n", cs->out ? "stop" : "resume",
 	    cs->user ? "user" : "kernel", cs->wmesg);
 }
 
-void
+static void
 ktruser(int len, void *p)
 {
 	unsigned char *cp;
@@ -1858,7 +1839,7 @@
 	printf("\n");
 }
 
-void
+static void
 ktrcaprights(cap_rights_t *rightsp)
 {
 
@@ -1874,7 +1855,7 @@
 	printf("{%ld, %ld}", (long)tv->tv_sec, tv->tv_usec);
 }
 
-void
+static void
 ktritimerval(struct itimerval *it)
 {
 
@@ -1885,7 +1866,7 @@
 	printf(" }\n");
 }
 
-void
+static void
 ktrsockaddr(struct sockaddr *sa)
 {
 /*
@@ -1960,7 +1941,7 @@
 	printf(" }\n");
 }
 
-void
+static void
 ktrsplice(struct splice *sp)
 {
 	printf("struct splice { fd=%d, max=%#jx, idle=%jd.%06jd }\n",
@@ -1968,7 +1949,7 @@
 	    (intmax_t)sp->sp_idle.tv_usec);
 }
 
-void
+static void
 ktrstat(struct stat *statp)
 {
 	char mode[12], timestr[PATH_MAX + 4];
@@ -2073,7 +2054,7 @@
 	printf(" }\n");
 }
 
-void
+static void
 ktrbitset(char *name, struct bitset *set, size_t setlen)
 {
 	int i, maxi, c = 0;
@@ -2097,7 +2078,7 @@
 		printf(" ]\n");
 }
 
-void
+static void
 ktrstruct(char *buf, size_t buflen)
 {
 	char *name, *data;
@@ -2174,7 +2155,7 @@
 	printf("invalid record\n");
 }
 
-void
+static void
 ktrcapfail(struct ktr_cap_fail *ktr)
 {
 	union ktr_cap_data *kcd = &ktr->cap_data;
@@ -2249,7 +2230,7 @@
 	printf("\n");
 }
 
-void
+static void
 ktrfault(struct ktr_fault *ktr)
 {
 
@@ -2258,7 +2239,7 @@
 	printf("\n");
 }
 
-void
+static void
 ktrfaultend(struct ktr_faultend *ktr)
 {
 	const char *str;
@@ -2271,7 +2252,7 @@
 	printf("\n");
 }
 
-void
+static void
 ktrkevent(struct kevent *kev)
 {
 
@@ -2302,7 +2283,7 @@
 	printf(", data=%#jx, udata=%p }", (uintmax_t)kev->data, kev->udata);
 }
 
-void
+static void
 ktrpollfd(struct pollfd *pfd)
 {
 
@@ -2314,7 +2295,7 @@
 	printf("}");
 }
 
-void
+static void
 ktrstructarray(struct ktr_struct_array *ksa, size_t buflen)
 {
 	struct kevent kev;
@@ -2420,7 +2401,18 @@
 	return;
 }
 
-void
+static void
+ktrexterr(struct ktr_exterr *ke)
+{
+	struct uexterror *ue;
+
+	ue = &ke->ue;
+	printf("{ errno %d category %u (src line %u) p1 %#jx p2 %#jx %s }",
+	    ue->error, ue->cat, ue->src_line,
+	    (uintmax_t)ue->p1, (uintmax_t)ue->p2, ue->msg);
+}
+
+static void
 usage(void)
 {
 	fprintf(stderr, "usage: kdump [-dEnlHRrSsTA] [-f trfile] "
diff --git a/usr.bin/ktrace/ktrace.h b/usr.bin/ktrace/ktrace.h
--- a/usr.bin/ktrace/ktrace.h
+++ b/usr.bin/ktrace/ktrace.h
@@ -32,7 +32,7 @@
 #define DEF_POINTS (KTRFAC_SYSCALL | KTRFAC_SYSRET | KTRFAC_NAMEI | \
 		    KTRFAC_GENIO | KTRFAC_PSIG | KTRFAC_USER | \
 		    KTRFAC_STRUCT | KTRFAC_SYSCTL | KTRFAC_STRUCT_ARRAY | \
-		    KTRFAC_ARGS | KTRFAC_ENVS)
+		    KTRFAC_ARGS | KTRFAC_ENVS | KTRFAC_EXTERR)
 
 #define PROC_ABI_POINTS (KTRFAC_PROCCTOR | KTRFAC_PROCDTOR)
 
diff --git a/usr.bin/ktrace/ktrace.1 b/usr.bin/ktrace/ktrace.1
--- a/usr.bin/ktrace/ktrace.1
+++ b/usr.bin/ktrace/ktrace.1
@@ -150,9 +150,13 @@
 trace
 .Xr execve 2
 environment variables
+.It Cm x
+trace
+.Xr exterr 2
+extended errors reports from kernel
 .It Cm +
 trace the default set of trace points -
-.Cm a, c , e,  i , n , s , t , u , y
+.Cm a, c , e,  i , n , s , t , u , x, y
 .El
 .It Ar command
 Execute
diff --git a/usr.bin/ktrace/subr.c b/usr.bin/ktrace/subr.c
--- a/usr.bin/ktrace/subr.c
+++ b/usr.bin/ktrace/subr.c
@@ -87,6 +87,8 @@
 		case 'e':
 		        facs |= KTRFAC_ENVS;
 			break;
+		case 'x':
+			facs |= KTRFAC_EXTERR;
 		case '+':
 			facs |= DEF_POINTS;
 			break;