# HG changeset patch
# Parent  f8524f7e5b59a6cfd43b780f5a8ee8e6d0346e3d
Add support for launching soft-float binaries with ld-elf-soft.so
instead of ld-elf.so ala ld-elf32.so.

Differential revision: https://reviews.freebsd.org/D2418

diff -r f8524f7e5b59 sys/arm/arm/elf_machdep.c
--- a/sys/arm/arm/elf_machdep.c
+++ b/sys/arm/arm/elf_machdep.c
@@ -47,6 +47,9 @@
 #include <machine/md_var.h>
 
 static boolean_t elf32_arm_abi_supported(struct image_params *);
+#ifdef COMPAT_ARM_SOFT_FLOAT
+static boolean_t elf32_arm_soft_supported(struct image_params *);
+#endif
 
 struct sysentvec elf32_freebsd_sysvec = {
 	.sv_size	= SYS_MAXSYSCALL,
@@ -100,6 +103,26 @@ SYSINIT(elf32, SI_SUB_EXEC, SI_ORDER_FIR
 	(sysinit_cfunc_t) elf32_insert_brand_entry,
 	&freebsd_brand_info);
 
+#ifdef COMPAT_ARM_SOFT_FLOAT
+static Elf32_Brandinfo freebsd_brand_info_soft = {
+	.brand		= ELFOSABI_FREEBSD,
+	.machine	= EM_ARM,
+	.compat_3_brand	= "FreeBSD",
+	.emul_path	= NULL,
+	.interp_path	= "/libexec/ld-elf.so.1",
+	.sysvec		= &elf32_freebsd_sysvec,
+	.interp_newpath	= "/libexec/ld-elf-soft.so.1",
+	.brand_note	= &elf32_freebsd_brandnote,
+	.flags		= BI_CAN_EXEC_DYN | BI_BRAND_NOTE,
+	.header_supported= elf32_arm_soft_supported,
+};
+
+SYSINIT(elf32soft, SI_SUB_EXEC, SI_ORDER_FIRST,
+	(sysinit_cfunc_t) elf32_insert_brand_entry,
+	&freebsd_brand_info_soft);
+#endif
+
+
 static boolean_t
 elf32_arm_abi_supported(struct image_params *imgp)
 {
@@ -107,16 +130,50 @@ elf32_arm_abi_supported(struct image_par
 
 	/*
 	 * When configured for EABI, FreeBSD supports EABI vesions 4 and 5.
+	 * The most common is version 0, OABI, which is a guaranteed core dump
+	 * if we execute it. Versions 1, 2, and 3 were never a FreeBSD thing,
+	 * so reject them.
 	 */
 	if (EF_ARM_EABI_VERSION(hdr->e_flags) < EF_ARM_EABI_FREEBSD_MIN) {
 		if (bootverbose)
-			uprintf("Attempting to execute non EABI binary (rev %d) image %s",
-			    EF_ARM_EABI_VERSION(hdr->e_flags), imgp->args->fname);
+			uprintf("Attempting to execute OABI binary image %s",
+			    imgp->args->fname);
 		return (FALSE);
 	}
+
+#ifdef COMPAT_ARM_SOFT_FLOAT
+	/*
+	 * When we're differentiating between hard and soft float, only execute
+	 * hard float excutables via this vector. We have a separate vector for
+	 * softfloat so it can use different libraries that are mutually
+	 * compatible.
+	 */
+	if ((hdr->e_flags & EF_ARM_VFP_FLOAT) == 0)
+		return (FALSE);
+#endif
 	return (TRUE);
 }
 
+#ifdef COMPAT_ARM_SOFT_FLOAT
+static boolean_t
+elf32_arm_soft_supported(struct image_params *imgp)
+{
+	const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header;
+
+	/*
+	 * Looking specifically for EABI 4 or 5 soft float programs.
+	 * Note: FreeBSD 10 and earlier didn't set EF_ARM_SOFT_FLOAT
+	 * on these binaries like it should have, so interpret
+	 * that as meaning 'soft float' too.
+	 */
+	if (EF_ARM_EABI_VERSION(hdr->e_flags) < EF_ARM_EABI_FREEBSD_MIN ||
+	    (hdr->e_flags & EF_ARM_VFP_FLOAT) != 0)
+		return (FALSE);
+
+	return (TRUE);
+}
+#endif
+
 void
 elf32_dump_thread(struct thread *td __unused, void *dst __unused,
     size_t *off __unused)
diff -r f8524f7e5b59 sys/conf/options.arm
--- a/sys/conf/options.arm
+++ b/sys/conf/options.arm
@@ -7,6 +7,7 @@ ARM_MANY_BOARD		opt_global.h
 ARM_NEW_PMAP		opt_global.h
 NKPT2PG			opt_pmap.h
 ARM_WANT_TP_ADDRESS	opt_global.h
+COMPAT_ARM_SOFT_FLOAT	opt_global.h
 COUNTS_PER_SEC		opt_timer.h
 CPU_ARM9		opt_global.h
 CPU_ARM9E		opt_global.h