diff --git a/lib/csu/common/crtbrand.c b/lib/csu/common/crtbrand.c
index 7e90144..e3309f8 100644
--- a/lib/csu/common/crtbrand.c
+++ b/lib/csu/common/crtbrand.c
@@ -43,7 +43,7 @@ static const struct {
     int32_t	type;
     char	name[sizeof ABI_VENDOR];
     int32_t	desc;
-} abitag __attribute__ ((section (ABI_SECTION), aligned(4))) __unused = {
+} abitag __attribute__ ((section (ABI_SECTION), aligned(4), used)) __unused = {
     sizeof ABI_VENDOR,
     sizeof(int32_t),
     ABI_NOTETYPE,
diff --git a/sys/amd64/amd64/trap.c b/sys/amd64/amd64/trap.c
index 62d81f6..577851f 100644
--- a/sys/amd64/amd64/trap.c
+++ b/sys/amd64/amd64/trap.c
@@ -144,6 +144,9 @@ SYSCTL_INT(_machdep, OID_AUTO, kdb_on_nmi, CTLFLAG_RW,
 static int panic_on_nmi = 1;
 SYSCTL_INT(_machdep, OID_AUTO, panic_on_nmi, CTLFLAG_RW,
 	&panic_on_nmi, 0, "Panic on NMI");
+static int prot_fault_translation = 0;
+SYSCTL_INT(_machdep, OID_AUTO, prot_fault_translation, CTLFLAG_RW,
+	&prot_fault_translation, 0, "Select signal to deliver on protection fault");
 
 extern char *syscallnames[];
 
@@ -312,8 +315,32 @@ trap(struct trapframe *frame)
 			if (i == SIGSEGV)
 				ucode = SEGV_MAPERR;
 			else {
-				i = SIGSEGV; /* XXX hack */
-				ucode = SEGV_ACCERR;
+				if (prot_fault_translation == 0) {
+					/*
+					 * Autodetect.
+					 * This check also covers the images
+					 * without the ABI-tag ELF note.
+					 */
+					if (p->p_osrel >= 700004) {
+						i = SIGSEGV;
+						ucode = SEGV_ACCERR;
+					} else {
+						i = SIGBUS;
+						ucode = BUS_PAGE_FAULT;
+					}
+				} else if (prot_fault_translation == 1) {
+					/*
+					 * Always compat mode.
+					 */
+					i = SIGBUS;
+					ucode = BUS_PAGE_FAULT;
+				} else {
+					/*
+					 * Always SIGSEGV mode.
+					 */
+					i = SIGSEGV;
+					ucode = SEGV_ACCERR;
+				}
 			}
 			break;
 
diff --git a/sys/i386/i386/trap.c b/sys/i386/i386/trap.c
index e66fa1e..cddffc0 100644
--- a/sys/i386/i386/trap.c
+++ b/sys/i386/i386/trap.c
@@ -158,6 +158,9 @@ SYSCTL_INT(_machdep, OID_AUTO, kdb_on_nmi, CTLFLAG_RW,
 static int panic_on_nmi = 1;
 SYSCTL_INT(_machdep, OID_AUTO, panic_on_nmi, CTLFLAG_RW,
 	&panic_on_nmi, 0, "Panic on NMI");
+static int prot_fault_translation = 0;
+SYSCTL_INT(_machdep, OID_AUTO, prot_fault_translation, CTLFLAG_RW,
+	&prot_fault_translation, 0, "Select signal to deliver on protection fault");
 
 extern char *syscallnames[];
 
@@ -375,8 +378,32 @@ trap(struct trapframe *frame)
 			if (i == SIGSEGV)
 				ucode = SEGV_MAPERR;
 			else {
-				i = SIGSEGV; /* XXX hack */
-				ucode = SEGV_ACCERR;
+				if (prot_fault_translation == 0) {
+					/*
+					 * Autodetect.
+					 * This check also covers the images
+					 * without the ABI-tag ELF note.
+					 */
+					if (p->p_osrel >= 700004) {
+						i = SIGSEGV;
+						ucode = SEGV_ACCERR;
+					} else {
+						i = SIGBUS;
+						ucode = BUS_PAGE_FAULT;
+					}
+				} else if (prot_fault_translation == 1) {
+					/*
+					 * Always compat mode.
+					 */
+					i = SIGBUS;
+					ucode = BUS_PAGE_FAULT;
+				} else {
+					/*
+					 * Always SIGSEGV mode.
+					 */
+					i = SIGSEGV;
+					ucode = SEGV_ACCERR;
+				}
 			}
 			addr = eva;
 			break;
diff --git a/sys/kern/imgact_elf.c b/sys/kern/imgact_elf.c
index 6c77244..3bf667f 100644
--- a/sys/kern/imgact_elf.c
+++ b/sys/kern/imgact_elf.c
@@ -106,6 +106,10 @@ SYSCTL_INT(_debug, OID_AUTO, __elfN(legacy_coredump), CTLFLAG_RW,
 
 static Elf_Brandinfo *elf_brand_list[MAX_BRANDS];
 
+#define trunc_page_ps(va, ps)	((va) & ~(ps - 1))
+#define round_page_ps(va, ps)	(((va) + (ps - 1)) & ~(ps - 1))
+#define aligned(a, t)	(trunc_page_ps((u_long)(a), sizeof(t)) == (u_long)(a))
+
 int
 __elfN(insert_brand_entry)(Elf_Brandinfo *entry)
 {
@@ -360,9 +364,6 @@ __elfN(load_section)(struct vmspace *vmspace,
 		return (ENOEXEC);
 	}
 
-#define trunc_page_ps(va, ps)	((va) & ~(ps - 1))
-#define round_page_ps(va, ps)	(((va) + (ps - 1)) & ~(ps - 1))
-
 	map_addr = trunc_page_ps((vm_offset_t)vmaddr, pagesize);
 	file_addr = trunc_page_ps(offset, pagesize);
 
@@ -549,6 +550,10 @@ __elfN(load_file)(struct proc *p, const char *file, u_long *addr,
 	}
 
 	phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
+	if (!aligned(phdr, Elf_Addr)) {
+		error = ENOEXEC;
+		goto fail;
+	}
 
 	for (i = 0, numsegs = 0; i < hdr->e_phnum; i++) {
 		if (phdr[i].p_type == PT_LOAD) {	/* Loadable segment */
@@ -592,11 +597,13 @@ fail:
 	return (error);
 }
 
+static const char FREEBSD_ABI_VENDOR[] = "FreeBSD";
+
 static int
 __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
 {
 	const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header;
-	const Elf_Phdr *phdr;
+	const Elf_Phdr *phdr, *pnote = NULL;
 	Elf_Auxargs *elf_auxargs;
 	struct vmspace *vmspace;
 	vm_prot_t prot;
@@ -607,7 +614,9 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
 	int error = 0, i;
 	const char *interp = NULL;
 	Elf_Brandinfo *brand_info;
+	const Elf_Note *note, *note_end;
 	char *path;
+	const char *note_name;
 	struct thread *td = curthread;
 	struct sysentvec *sv;
 
@@ -632,6 +641,8 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
 		return (ENOEXEC);
 	}
 	phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff);
+	if (!aligned(phdr, Elf_Addr))
+		return (ENOEXEC);
 	for (i = 0; i < hdr->e_phnum; i++) {
 		if (phdr[i].p_type == PT_INTERP) {
 			/* Path to interpreter */
@@ -747,6 +758,11 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
 		case PT_PHDR: 	/* Program header table info */
 			proghdr = phdr[i].p_vaddr;
 			break;
+		case PT_NOTE:
+			pnote = &phdr[i];
+			if (!aligned(pnote, Elf32_Addr))
+				return (ENOEXEC);
+			break;
 		default:
 			break;
 		}
@@ -828,6 +844,36 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
 	imgp->auxargs = elf_auxargs;
 	imgp->interpreted = 0;
 
+	/*
+	 * Try to fetch the osreldate for FreeBSD binary from the ELF
+	 * OSABI-note. Only the first page of the image is searched,
+	 * the same as for headers.
+	 */
+	if (pnote != NULL && pnote->p_offset < PAGE_SIZE &&
+	    pnote->p_offset + pnote->p_filesz < PAGE_SIZE ) {
+		note = (const Elf_Note *)(imgp->image_header + pnote->p_offset);
+		note_end = (const Elf_Note *)(imgp->image_header + pnote->p_offset +
+		    pnote->p_filesz);
+		while (note < note_end) {
+			if (note->n_namesz == sizeof(FREEBSD_ABI_VENDOR) &&
+			    note->n_descsz == sizeof(int32_t) &&
+			    note->n_type == 1 /* ABI_NOTETYPE */) {
+				note_name = (const char *)(note + 1);
+				if (strncmp(FREEBSD_ABI_VENDOR, note_name,
+				    sizeof(FREEBSD_ABI_VENDOR)) == 0) {
+					imgp->proc->p_osrel = *(const int32_t *)
+					    (note_name +
+					    round_page_ps(sizeof(FREEBSD_ABI_VENDOR),
+						sizeof(Elf32_Addr)));
+					break;
+				}
+			}
+			note = (const Elf_Note *)((const char *)(note + 1) +
+			    round_page_ps(note->n_namesz, sizeof(Elf32_Addr)) +
+			    round_page_ps(note->n_descsz, sizeof(Elf32_Addr)));
+		}
+	}
+
 	return (error);
 }
 
@@ -894,8 +940,6 @@ static void __elfN(puthdr)(struct thread *, void *, size_t *, int);
 static void __elfN(putnote)(void *, size_t *, const char *, int,
     const void *, size_t);
 
-extern int osreldate;
-
 int
 __elfN(coredump)(td, vp, limit)
 	struct thread *td;
diff --git a/sys/kern/init_main.c b/sys/kern/init_main.c
index d4c04e5..3a85150 100644
--- a/sys/kern/init_main.c
+++ b/sys/kern/init_main.c
@@ -373,9 +373,10 @@ proc0_init(void *dummy __unused)
 	td = &thread0;
 	
 	/*
-	 * Initialize magic number.
+	 * Initialize magic number and osrel.
 	 */
 	p->p_magic = P_MAGIC;
+	p->p_osrel = osreldate;
 
 	/*
 	 * Initialize thread and process structures.
diff --git a/sys/kern/kern_exec.c b/sys/kern/kern_exec.c
index 2d32c34..6545614 100644
--- a/sys/kern/kern_exec.c
+++ b/sys/kern/kern_exec.c
@@ -391,6 +391,7 @@ interpret:
 	if (error)
 		goto exec_fail_dealloc;
 
+	imgp->proc->p_osrel = 0;
 	/*
 	 *	If the current process has a special image activator it
 	 *	wants to try first, call it.   For example, emulating shell
diff --git a/sys/kern/kern_mib.c b/sys/kern/kern_mib.c
index 7280c52..78a9445 100644
--- a/sys/kern/kern_mib.c
+++ b/sys/kern/kern_mib.c
@@ -104,7 +104,6 @@ SYSCTL_STRING(_kern, KERN_OSTYPE, ostype, CTLFLAG_RD,
  * NOTICE: The *userland* release date is available in
  * /usr/include/osreldate.h
  */
-extern int osreldate;
 SYSCTL_INT(_kern, KERN_OSRELDATE, osreldate, CTLFLAG_RD,
     &osreldate, 0, "Kernel release date");
 
diff --git a/sys/sys/proc.h b/sys/sys/proc.h
index 54a8413..d75acb9 100644
--- a/sys/sys/proc.h
+++ b/sys/sys/proc.h
@@ -561,6 +561,8 @@ struct proc {
 /* The following fields are all copied upon creation in fork. */
 #define	p_startcopy	p_endzero
 	u_int		p_magic;	/* (b) Magic number. */
+	int		p_osrel;	/* (x) osreldate for the
+					       binary (from ELF note, if any) */
 	char		p_comm[MAXCOMLEN + 1];	/* (b) Process name. */
 	struct pgrp	*p_pgrp;	/* (c + e) Pointer to process group. */
 	struct sysentvec *p_sysent;	/* (b) Syscall dispatch info. */
diff --git a/sys/sys/systm.h b/sys/sys/systm.h
index 1a9d964..95bc05f 100644
--- a/sys/sys/systm.h
+++ b/sys/sys/systm.h
@@ -101,6 +101,7 @@ extern int maxusers;		/* system tune hint */
  * in two files.
  * XXX most of these variables should be const.
  */
+extern int osreldate;
 extern int envmode;
 extern int hintmode;		/* 0 = off. 1 = config, 2 = fallback */
 extern int dynamic_kenv;