hppa: fix runtime issues

Sync clone()/vfork() with GNU C Library.
Allow CFI and fix strsignal() / tcsetattr().

7 files changed, 568 insertions, 67 deletions

diff --git a/libc/string/strsignal.c b/libc/string/strsignal.c
index 0fbbf8504..0c1ba02c9 100644
--- a/libc/string/strsignal.c
+++ b/libc/string/strsignal.c
@@ -36,7 +36,7 @@
 
 extern const char _string_syssigmsgs[] attribute_hidden;
 
-#if defined(__alpha__) || defined(__mips__) || defined(__hppa__) || defined(__sparc__)
+#if defined(__alpha__) || defined(__mips__) || defined(__sparc__)
 static const unsigned char sstridx[] = {
 	0,
 	SIGHUP,
@@ -89,7 +89,7 @@ char *strsignal(int signum)
 		'U', 'n', 'k', 'n', 'o', 'w', 'n', ' ', 's', 'i', 'g', 'n', 'a', 'l', ' '
 	};
 
-#if defined(__alpha__) || defined(__mips__) || defined(__hppa__) || defined(__sparc__)
+#if defined(__alpha__) || defined(__mips__) || defined(__sparc__)
 	/* Need to translate signum to string index. */
 	for (i = 0; i < sizeof(sstridx)/sizeof(sstridx[0]); i++) {
 		if (sstridx[i] == signum) {
diff --git a/libc/sysdeps/linux/hppa/Makefile.arch b/libc/sysdeps/linux/hppa/Makefile.arch
index 621a5b314..90cf5a4bc 100644
--- a/libc/sysdeps/linux/hppa/Makefile.arch
+++ b/libc/sysdeps/linux/hppa/Makefile.arch
@@ -8,4 +8,4 @@
 CSRC-y := __syscall_error.c brk.c syscall.c
 
 SSRC-y := __longjmp.S bsd-_setjmp.S bsd-setjmp.S clone.S setjmp.S \
-	add_n.s lshift.s rshift.s sub_n.s udiv_qrnnd.s
+	add_n.s lshift.s rshift.s sub_n.s udiv_qrnnd.s vfork.S
diff --git a/libc/sysdeps/linux/hppa/bits/ioctls.h b/libc/sysdeps/linux/hppa/bits/ioctls.h
new file mode 100644
index 000000000..99ecb0ff1
--- /dev/null
+++ b/libc/sysdeps/linux/hppa/bits/ioctls.h
@@ -0,0 +1,35 @@
+/* Copyright (C) 1996-2018 Free Software Foundation, Inc.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _SYS_IOCTL_H
+# error "Never use <bits/ioctls.h> directly; include <sys/ioctl.h> instead."
+#endif
+
+/* Use the definitions from the kernel header files.  */
+#include <asm/ioctls.h>
+
+/* Oh well, this is necessary since the kernel data structure is
+   different from the user-level version.  */
+#undef  TCGETS
+#undef  TCSETS
+#undef  TCSETSW
+#undef  TCSETSF
+#define TCGETS	_IOR ('T', 16, char[36])
+#define TCSETS	_IOW ('T', 17, char[36])
+#define TCSETSW	_IOW ('T', 18, char[36])
+#define TCSETSF	_IOW ('T', 19, char[36])
+
+#include <linux/sockios.h>
diff --git a/libc/sysdeps/linux/hppa/bits/uClibc_arch_features.h b/libc/sysdeps/linux/hppa/bits/uClibc_arch_features.h
index 19fa05109..1c096bd17 100644
--- a/libc/sysdeps/linux/hppa/bits/uClibc_arch_features.h
+++ b/libc/sysdeps/linux/hppa/bits/uClibc_arch_features.h
@@ -30,7 +30,7 @@
 #undef __UCLIBC_HAVE_ASM_WEAKEXT_DIRECTIVE__
 
 /* define if target supports CFI pseudo ops */
-#undef __UCLIBC_HAVE_ASM_CFI_DIRECTIVES__
+#define __UCLIBC_HAVE_ASM_CFI_DIRECTIVES__
 
 /* define if target supports IEEE signed zero floats */
 #define __UCLIBC_HAVE_SIGNED_ZERO__
diff --git a/libc/sysdeps/linux/hppa/clone.S b/libc/sysdeps/linux/hppa/clone.S
index f6c153b01..8356d9a74 100644
--- a/libc/sysdeps/linux/hppa/clone.S
+++ b/libc/sysdeps/linux/hppa/clone.S
@@ -1,5 +1,4 @@
-/* Copyright (C) 1996, 1997, 2000 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
+/* Copyright (C) 1996-2018 Free Software Foundation, Inc.
    Contributed by David Huggins-Daines <dhd@debian.org>, 2000.
    Based on the Alpha version by Richard Henderson <rth@tamu.edu>, 1996.
 
@@ -14,27 +13,35 @@
    Lesser General Public License for more details.
 
    You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, see
+   License along with the GNU C Library.  If not, see
    <http://www.gnu.org/licenses/>.  */
 
 /* clone() is even more special than fork() as it mucks with stacks
    and invokes a function in the right context after its all over.  */
 
 #include <asm/unistd.h>
+#include <sysdep.h>
 #define _ERRNO_H	1
 #include <bits/errno.h>
-#include <sys/syscall.h>
 
 /* Non-thread code calls __clone with the following parameters:
-   int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg)
-   
+   int clone(int (*fn)(void *arg),
+	     void *child_stack,
+	     int flags,
+	     void *arg)
+
    NPTL Code will call __clone with the following parameters:
-   int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg,
-	     int *parent_tidptr, struct user_desc *newtls, int *child_pidptr)
-	
+   int clone(int (*fn)(void *arg),
+	     void *child_stack,
+	     int flags,
+	     void *arg,
+	     int *parent_tidptr,
+	     struct user_desc *newtls,
+	     int *child_pidptr)
+
    The code should not mangle the extra input registers.
    Syscall expects:				Input to __clone:
-	4(r25) - function pointer 		(r26, arg0) 
+	4(r25) - function pointer 		(r26, arg0)
 	0(r25) - argument			(r23, arg3)
 	r26 - clone flags.			(r24, arg2)
 	r25+64 - user stack pointer.		(r25, arg1)
@@ -42,93 +49,114 @@
 	r23 - struct user_desc newtls pointer.	(stack - 56)
 	r22 - child tid pointer.		(stack - 60)
 	r20 - clone syscall number		(constant)
+
+   Return:
+
+	On success the thread ID of the child process is returend in
+	the callers context.
+	On error return -1, and set errno to the value returned by
+	the syscall.
  */
 
-.text
-.global __clone
-.type   __clone,%function
-__clone:
+        .text
+ENTRY(__clone)
+	/* Prologue */
+	stwm	%r4, 64(%sp)
+	.cfi_def_cfa_offset -64
+	.cfi_offset 4, 0
+	stw	%sp, -4(%sp)
+#ifdef __PIC__
+	stw	%r19, -32(%sp)
+	.cfi_offset 19, 32
+#endif
 
 	/* Sanity check arguments.  */
-	ldi     -EINVAL,%ret0
-	comib,=,n  0,%arg0,.Lerror        /* no NULL function pointers */
-	comib,=,n  0,%arg1,.Lerror        /* no NULL stack pointers */
+	comib,=,n  0, %arg0, .LerrorSanity        /* no NULL function pointers */
+	comib,=,n  0, %arg1, .LerrorSanity        /* no NULL stack pointers */
 
-	/* Save the fn ptr and arg on the new stack.  */
-	stwm    %r26,64(%r25)
-	stw	%r23,-60(%r25)
+	/* Save the function pointer, arg, and flags on the new stack.  */
+	stwm    %r26, 64(%r25)
+	stw	%r23, -60(%r25)
+	stw     %r24, -56(%r25)
 	/* Clone arguments are (int flags, void * child_stack) */
-	copy	%r24,%r26	/* flags are first */
+	copy	%r24, %r26		/* flags are first */
 	/* User stack pointer is in the correct register already */
 
 	/* Load args from stack... */
-	ldw	-52(%sp), %r24	/* Load parent_tidptr */
-	ldw	-56(%sp), %r23 	/* Load newtls */
-	ldw	-60(%sp), %r22	/* Load child_tidptr */
-
-	/* Create frame to get r3 free */
-	copy	%sp, %r21
-	stwm	%r3, 64(%sp)
-	stw	%r21, -4(%sp)
+	ldw	-116(%sp), %r24		/* Load parent_tidptr */
+	ldw	-120(%sp), %r23 	/* Load newtls */
+	ldw	-124(%sp), %r22		/* Load child_tidptr */
 
 	/* Save the PIC register. */
 #ifdef __PIC__
-	copy	%r19, %r3		/* parent */
+	copy	%r19, %r4		/* parent */
 #endif
 
 	/* Do the system call */
-	ble     0x100(%sr2,%r0)
-	ldi	__NR_clone,%r20
+	ble     0x100(%sr2, %r0)
+	ldi	__NR_clone, %r20
 
-	ldi	-4096,%r1
-	comclr,>>= %r1,%ret0,%r0	/* Note: unsigned compare. */
+	ldi	-4096, %r1
+	comclr,>>= %r1, %ret0, %r0	/* Note: unsigned compare. */
 	b,n	.LerrorRest
 
-	comib,=,n 0,%ret0,thread_start
+	/* Restore the PIC register.  */
+#ifdef __PIC__
+	copy	%r4, %r19		/* parent */
+#endif
+
+	comib,=,n 0, %ret0, .LthreadStart
 
 	/* Successful return from the parent
-	   No need to restore the PIC register, 
+	   No need to restore the PIC register,
 	   since we return immediately. */
 
+	ldw	-84(%sp), %rp
 	bv	%r0(%rp)
-	ldwm	-64(%sp), %r3
+	ldwm	-64(%sp), %r4
 
 .LerrorRest:
-	/* Restore the PIC register on error */
-#ifdef __PIC__
-	copy	%r3, %r19		/* parent */ 
-#endif
-
 	/* Something bad happened -- no child created */
-.Lerror:
-
-	/* Set errno, save ret0 so we return with that value. */
-	copy	%ret0, %r3
-	b	__syscall_error
-	sub     %r0,%ret0,%arg0
-	copy	%r3, %ret0
-	/* Return after setting errno, and restoring ret0 */
+	bl	__syscall_error, %rp
+	sub     %r0, %ret0, %arg0
+	ldw	-84(%sp), %rp
+	/* Return after setting errno, ret0 is set to -1 by __syscall_error. */
 	bv	%r0(%rp)
-	ldwm	-64(%sp), %r3
+	ldwm	-64(%sp), %r4
 
-thread_start:
+.LerrorSanity:
+	/* Sanity checks failed, return -1, and set errno to EINVAL. */
+	bl	__syscall_error, %rp
+	ldi     EINVAL, %arg0
+	ldw	-84(%sp), %rp
+	bv	%r0(%rp)
+	ldwm	-64(%sp), %r4
 
+.LthreadStart:
 	/* Load up the arguments.  */
-	ldw	-60(%sr0, %sp),%arg0
-	ldw     -64(%sr0, %sp),%r22
+	ldw	-60(%sp), %arg0
+	ldw     -64(%sp), %r22
 
-	/* $$dyncall fixes childs PIC register */
+	/* $$dyncall fixes child's PIC register */
 
 	/* Call the user's function */
-	bl	$$dyncall,%r31
-	copy	%r31,%rp
-
-	bl	HIDDEN_JUMPTARGET(_exit),%rp
-	copy	%ret0,%arg0
+#ifdef __PIC__
+	copy	%r19, %r4
+#endif
+	bl	$$dyncall, %r31
+	copy	%r31, %rp
+#ifdef __PIC__
+	copy	%r4, %r19
+#endif
+	copy	%r28, %r26
+	ble     0x100(%sr2, %r0)
+	ldi	__NR_exit, %r20
 
-	/* Die horribly.  */
-	iitlbp	%r0,(%sr0,%r0)
+	/* We should not return from exit.
+           We do not restore r4, or the stack state.  */
+	iitlbp	%r0, (%sr0, %r0)
 
-.size clone,.-clone
+PSEUDO_END(__clone)
 
+libc_hidden_def (__clone)
 weak_alias (__clone, clone)
diff --git a/libc/sysdeps/linux/hppa/sysdep.h b/libc/sysdeps/linux/hppa/sysdep.h
new file mode 100644
index 000000000..57b0cba9b
--- /dev/null
+++ b/libc/sysdeps/linux/hppa/sysdep.h
@@ -0,0 +1,356 @@
+/* Assembler macros for PA-RISC.
+   Copyright (C) 1999-2018 Free Software Foundation, Inc.
+   Contributed by Ulrich Drepper, <drepper@cygnus.com>, August 1999.
+   Linux/PA-RISC changes by Philipp Rumpf, <prumpf@tux.org>, March 2000.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _LINUX_HPPA_SYSDEP_H
+#define _LINUX_HPPA_SYSDEP_H 1
+
+#include <common/sysdep.h>
+#include <sys/syscall.h>
+
+/* In order to get __set_errno() definition in INLINE_SYSCALL.  */
+#ifndef __ASSEMBLER__
+#include <errno.h>
+#endif
+
+#undef ASM_LINE_SEP
+#define ASM_LINE_SEP !
+
+#undef SYS_ify
+#define SYS_ify(syscall_name)	(__NR_##syscall_name)
+
+/* The vfork, fork, and clone syscalls clobber r19
+ * and r21. We list r21 as either clobbered or as an
+ * input to a 6-argument syscall. We must save and
+ * restore r19 in both PIC and non-PIC cases.
+ */
+/* WARNING: TREG must be a callee saves register so
+   that it doesn't have to be restored after a call
+   to another function */
+#define TREG 4
+#define SAVE_PIC(SREG) \
+	copy %r19, SREG
+#define LOAD_PIC(LREG) \
+	copy LREG , %r19
+/* Inline assembly defines */
+#define TREG_ASM "%r4" /* Cant clobber r3, it holds framemarker */
+#define SAVE_ASM_PIC	"       copy %%r19, %" TREG_ASM "\n"
+#define LOAD_ASM_PIC	"       copy %" TREG_ASM ", %%r19\n"
+#define CLOB_TREG	TREG_ASM ,
+#define PIC_REG_DEF	register unsigned long __r19 asm("r19");
+#define PIC_REG_USE	, "r" (__r19)
+
+#ifdef __ASSEMBLER__
+
+/* Syntactic details of assembler.  */
+
+#define ALIGNARG(log2) log2
+
+/* For Linux we can use the system call table in the header file
+	/usr/include/asm/unistd.h
+   of the kernel.  But these symbols do not follow the SYS_* syntax
+   so we have to redefine the `SYS_ify' macro here.  */
+#undef SYS_ify
+#define SYS_ify(syscall_name)	__NR_##syscall_name
+
+/* ELF-like local names start with `.L'.  */
+#undef L
+#define L(name)	.L##name
+
+/* Linux uses a negative return value to indicate syscall errors,
+   unlike most Unices, which use the condition codes' carry flag.
+
+   Since version 2.1 the return value of a system call might be
+   negative even if the call succeeded.  E.g., the `lseek' system call
+   might return a large offset.  Therefore we must not anymore test
+   for < 0, but test for a real error by making sure the value in %eax
+   is a real error number.  Linus said he will make sure the no syscall
+   returns a value in -1 .. -4095 as a valid result so we can safely
+   test with -4095.  */
+
+/* We don't want the label for the error handle to be global when we define
+   it here.  */
+/*#ifdef PIC
+# define SYSCALL_ERROR_LABEL 0f
+#else
+# define SYSCALL_ERROR_LABEL syscall_error
+#endif*/
+
+/* Argument manipulation from the stack for preparing to
+   make a syscall */
+
+#define DOARGS_0 /* nothing */
+#define DOARGS_1 /* nothing */
+#define DOARGS_2 /* nothing */
+#define DOARGS_3 /* nothing */
+#define DOARGS_4 /* nothing */
+#define DOARGS_5 ldw -52(%sp), %r22		ASM_LINE_SEP
+#define DOARGS_6 DOARGS_5 ldw -56(%sp), %r21	ASM_LINE_SEP
+
+#define UNDOARGS_0 /* nothing */
+#define UNDOARGS_1 /* nothing */
+#define UNDOARGS_2 /* nothing */
+#define UNDOARGS_3 /* nothing */
+#define UNDOARGS_4 /* nothing */
+#define UNDOARGS_5 /* nothing */
+#define UNDOARGS_6 /* nothing */
+
+/* Define an entry point visible from C.
+
+   There is currently a bug in gdb which prevents us from specifying
+   incomplete stabs information.  Fake some entries here which specify
+   the current source file.  */
+#undef ENTRY
+#define	ENTRY(name)							\
+	.text						ASM_LINE_SEP	\
+	.align ALIGNARG(4)				ASM_LINE_SEP	\
+	.export C_SYMBOL_NAME(name)			ASM_LINE_SEP	\
+	.type	C_SYMBOL_NAME(name),@function		ASM_LINE_SEP	\
+	cfi_startproc					ASM_LINE_SEP	\
+	C_LABEL(name)					ASM_LINE_SEP	\
+	.PROC						ASM_LINE_SEP	\
+	.CALLINFO FRAME=64,CALLS,SAVE_RP,ENTRY_GR=3	ASM_LINE_SEP	\
+	.ENTRY						ASM_LINE_SEP	\
+	/* SAVE_RP says we do */			ASM_LINE_SEP	\
+	stw %rp, -20(%sr0,%sp)				ASM_LINE_SEP	\
+	.cfi_offset 2, -20				ASM_LINE_SEP	\
+	/*FIXME: Call mcount? (carefull with stack!) */
+
+/* Some syscall wrappers do not call other functions, and
+   hence are classified as leaf, so add NO_CALLS for gdb */
+#define	ENTRY_LEAF(name)						\
+	.text						ASM_LINE_SEP	\
+	.align ALIGNARG(4)				ASM_LINE_SEP	\
+	.export C_SYMBOL_NAME(name)			ASM_LINE_SEP	\
+	.type	C_SYMBOL_NAME(name),@function		ASM_LINE_SEP	\
+	cfi_startproc					ASM_LINE_SEP	\
+	C_LABEL(name)					ASM_LINE_SEP	\
+	.PROC						ASM_LINE_SEP	\
+	.CALLINFO FRAME=64,NO_CALLS,SAVE_RP,ENTRY_GR=3	ASM_LINE_SEP	\
+	.ENTRY						ASM_LINE_SEP	\
+	/* SAVE_RP says we do */			ASM_LINE_SEP	\
+	stw %rp, -20(%sr0,%sp)				ASM_LINE_SEP	\
+	.cfi_offset 2, -20				ASM_LINE_SEP	\
+	/*FIXME: Call mcount? (carefull with stack!) */
+
+#undef	END
+#define END(name)							\
+	.EXIT						ASM_LINE_SEP	\
+	.PROCEND					ASM_LINE_SEP	\
+	cfi_endproc					ASM_LINE_SEP	\
+.size	C_SYMBOL_NAME(name), .-C_SYMBOL_NAME(name)	ASM_LINE_SEP
+
+/* If compiled for profiling, call `mcount' at the start
+   of each function. No, don't bother.  gcc will put the
+   call in for us.  */
+#define CALL_MCOUNT		/* Do nothing.  */
+
+/* syscall wrappers consist of
+	#include <sysdep.h>
+	PSEUDO(...)
+	ret
+	PSEUDO_END(...)
+
+   which means
+	ENTRY(name)
+	DO_CALL(...)
+	bv,n 0(2)
+*/
+
+#undef PSEUDO
+#define	PSEUDO(name, syscall_name, args)			\
+  ENTRY (name)					ASM_LINE_SEP	\
+  /* If necc. load args from stack */		ASM_LINE_SEP	\
+  DOARGS_##args					ASM_LINE_SEP	\
+  DO_CALL (syscall_name, args)			ASM_LINE_SEP	\
+  UNDOARGS_##args				ASM_LINE_SEP
+
+#define ret \
+  /* Return value set by ERRNO code */		ASM_LINE_SEP	\
+  bv,n 0(2)					ASM_LINE_SEP
+
+#undef	PSEUDO_END
+#define	PSEUDO_END(name)					\
+  END (name)
+
+/* We don't set the errno on the return from the syscall */
+#define	PSEUDO_NOERRNO(name, syscall_name, args)		\
+  ENTRY_LEAF (name)				ASM_LINE_SEP	\
+  DOARGS_##args					ASM_LINE_SEP	\
+  DO_CALL_NOERRNO (syscall_name, args)		ASM_LINE_SEP	\
+  UNDOARGS_##args				ASM_LINE_SEP
+
+#define ret_NOERRNO ret
+
+#undef	PSEUDO_END_NOERRNO
+#define	PSEUDO_END_NOERRNO(name)				\
+  END (name)
+
+/* This has to return the error value */
+#undef  PSEUDO_ERRVAL
+#define PSEUDO_ERRVAL(name, syscall_name, args)			\
+  ENTRY_LEAF (name)				ASM_LINE_SEP	\
+  DOARGS_##args					ASM_LINE_SEP	\
+  DO_CALL_ERRVAL (syscall_name, args)		ASM_LINE_SEP	\
+  UNDOARGS_##args				ASM_LINE_SEP
+
+#define ret_ERRVAL ret
+
+#undef	PSEUDO_END_ERRVAL
+#define PSEUDO_END_ERRVAL(name)					\
+	END(name)
+
+#undef JUMPTARGET
+#define JUMPTARGET(name)	name
+#define SYSCALL_PIC_SETUP	/* Nothing.  */
+
+
+/* FIXME: This comment is not true.
+ * All the syscall assembly macros rely on finding the appropriate
+   SYSCALL_ERROR_LABEL or rather HANDLER. */
+
+/* int * __errno_location(void) so you have to store your value
+   into the return address! */
+#define DEFAULT_SYSCALL_ERROR_HANDLER			\
+	.import __errno_location,code	ASM_LINE_SEP	\
+	/* branch to errno handler */	ASM_LINE_SEP	\
+	bl __errno_location,%rp		ASM_LINE_SEP
+
+/* Here are the myriad of configuration options that the above can
+   work for... what we've done is provide the framework for future
+   changes if required to each section */
+
+#ifdef __PIC__
+#  if defined _LIBC_REENTRANT
+#   define SYSCALL_ERROR_HANDLER DEFAULT_SYSCALL_ERROR_HANDLER
+#  else /* !_LIBC_REENTRANT */
+#   define SYSCALL_ERROR_HANDLER DEFAULT_SYSCALL_ERROR_HANDLER
+#  endif /* _LIBC_REENTRANT */
+#else
+# ifndef _LIBC_REENTRANT
+#  define SYSCALL_ERROR_HANDLER DEFAULT_SYSCALL_ERROR_HANDLER
+# else
+#  define SYSCALL_ERROR_HANDLER DEFAULT_SYSCALL_ERROR_HANDLER
+# endif
+#endif
+
+
+/* Linux takes system call arguments in registers:
+	syscall number	gr20
+	arg 1		gr26
+	arg 2		gr25
+	arg 3		gr24
+	arg 4		gr23
+	arg 5		gr22
+	arg 6		gr21
+
+   The compiler calls us by the C convention:
+	syscall number	in the DO_CALL macro
+	arg 1		gr26
+	arg 2		gr25
+	arg 3		gr24
+	arg 4		gr23
+	arg 5		-52(sp)
+	arg 6		-56(sp)
+
+   gr22 and gr21 are caller-saves, so we can just load the arguments
+   there and generally be happy. */
+
+/* the cmpb...no_error code below inside DO_CALL
+ * is intended to mimic the if (__sys_res...)
+ * code inside INLINE_SYSCALL
+ */
+#define NO_ERROR -0x1000
+
+#undef	DO_CALL
+#define DO_CALL(syscall_name, args)				\
+	/* Create a frame */			ASM_LINE_SEP	\
+	stwm TREG, 64(%sp)			ASM_LINE_SEP	\
+	.cfi_def_cfa_offset -64			ASM_LINE_SEP	\
+	.cfi_offset TREG, 0			ASM_LINE_SEP	\
+	stw %sp, -4(%sp)			ASM_LINE_SEP	\
+	stw %r19, -32(%sp)			ASM_LINE_SEP	\
+	.cfi_offset 19, 32			ASM_LINE_SEP	\
+	/* Save r19 */				ASM_LINE_SEP	\
+	SAVE_PIC(TREG)				ASM_LINE_SEP	\
+	/* Do syscall, delay loads # */		ASM_LINE_SEP	\
+	ble  0x100(%sr2,%r0)			ASM_LINE_SEP	\
+	ldi SYS_ify (syscall_name), %r20	ASM_LINE_SEP	\
+	ldi NO_ERROR,%r1			ASM_LINE_SEP	\
+	cmpb,>>=,n %r1,%ret0,L(pre_end)		ASM_LINE_SEP	\
+	/* Restore r19 from TREG */		ASM_LINE_SEP	\
+	LOAD_PIC(TREG) /* delay */		ASM_LINE_SEP	\
+	SYSCALL_ERROR_HANDLER			ASM_LINE_SEP	\
+	/* Use TREG for temp storage */		ASM_LINE_SEP	\
+	copy %ret0, TREG /* delay */		ASM_LINE_SEP	\
+	/* OPTIMIZE: Don't reload r19 */	ASM_LINE_SEP	\
+	/* do a -1*syscall_ret0 */		ASM_LINE_SEP	\
+	sub %r0, TREG, TREG			ASM_LINE_SEP	\
+	/* Store into errno location */		ASM_LINE_SEP	\
+	stw TREG, 0(%sr0,%ret0)			ASM_LINE_SEP	\
+	/* return -1 as error */		ASM_LINE_SEP	\
+	ldo -1(%r0), %ret0			ASM_LINE_SEP	\
+L(pre_end):					ASM_LINE_SEP	\
+	/* Restore our frame, restoring TREG */	ASM_LINE_SEP	\
+	ldwm -64(%sp), TREG			ASM_LINE_SEP	\
+	/* Restore return pointer */		ASM_LINE_SEP	\
+	ldw -20(%sp),%rp			ASM_LINE_SEP
+
+/* We do nothing with the return, except hand it back to someone else */
+#undef  DO_CALL_NOERRNO
+#define DO_CALL_NOERRNO(syscall_name, args)			\
+	/* No need to store r19 */		ASM_LINE_SEP	\
+	ble  0x100(%sr2,%r0)                    ASM_LINE_SEP    \
+	ldi SYS_ify (syscall_name), %r20        ASM_LINE_SEP    \
+	/* Caller will restore r19 */		ASM_LINE_SEP
+
+/* Here, we return the ERRVAL in assembly, note we don't call the
+   error handler function, but we do 'negate' the return _IF_
+   it's an error. Not sure if this is the right semantic. */
+
+#undef	DO_CALL_ERRVAL
+#define DO_CALL_ERRVAL(syscall_name, args)			\
+	/* No need to store r19 */		ASM_LINE_SEP	\
+	ble  0x100(%sr2,%r0)			ASM_LINE_SEP	\
+	ldi SYS_ify (syscall_name), %r20	ASM_LINE_SEP	\
+	/* Caller will restore r19 */		ASM_LINE_SEP	\
+	ldi NO_ERROR,%r1			ASM_LINE_SEP	\
+	cmpb,>>=,n %r1,%ret0,0f			ASM_LINE_SEP	\
+	sub %r0, %ret0, %ret0			ASM_LINE_SEP	\
+0:						ASM_LINE_SEP
+
+
+#else
+
+/* GCC has to be warned that a syscall may clobber all the ABI
+   registers listed as "caller-saves", see page 8, Table 2
+   in section 2.2.6 of the PA-RISC RUN-TIME architecture
+   document. However! r28 is the result and will conflict with
+   the clobber list so it is left out. Also the input arguments
+   registers r20 -> r26 will conflict with the list so they
+   are treated specially. Although r19 is clobbered by the syscall
+   we cannot say this because it would violate ABI, thus we say
+   TREG is clobbered and use that register to save/restore r19
+   across the syscall. */
+
+#define CALL_CLOB_REGS	"%r1", "%r2", CLOB_TREG \
+			"%r20", "%r29", "%r31"
+
+#endif	/* __ASSEMBLER__ */
+
+#endif /* _LINUX_HPPA_SYSDEP_H */
diff --git a/libc/sysdeps/linux/hppa/vfork.S b/libc/sysdeps/linux/hppa/vfork.S
new file mode 100644
index 000000000..9d0706361
--- /dev/null
+++ b/libc/sysdeps/linux/hppa/vfork.S
@@ -0,0 +1,82 @@
+/* Copyright (C) 2005-2018 Free Software Foundation, Inc.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+#define _ERRNO_H        1
+#include <bits/errno.h>
+
+/* Clone the calling process, but without copying the whole address space.
+   The calling process is suspended until the new process exits or is
+   replaced by a call to `execve'.  Return -1 for errors, 0 to the new process,
+   and the process ID of the new process to the old process.  */
+
+.Lthread_start:						ASM_LINE_SEP
+
+	/* r26, r25, r24, r23 are free since vfork has no arguments */
+ENTRY(__vfork)
+	/* We must not create a frame. When the child unwinds to call
+	   exec it will clobber the same frame that the parent
+	   needs to unwind.  */
+
+	/* Save the PIC register. */
+#ifdef __PIC__
+	copy	%r19, %r25	/* parent */
+#endif
+
+	/* Syscall saves and restores all register states */
+	ble	0x100(%sr2,%r0)
+	ldi	__NR_vfork,%r20
+
+	/* Check for error */
+	ldi	-4096,%r1
+	comclr,>>= %r1,%ret0,%r0        /* Note: unsigned compare. */
+	b,n	.Lerror
+
+	/* Return, and DO NOT restore rp. The child may have called
+	   functions that updated the frame's rp. This works because
+	   the kernel ensures rp is preserved across the vfork
+	   syscall.  */
+	bv,n	%r0(%rp)
+
+.Lerror:
+	/* Now we need a stack to call a function. We are assured
+	   that there is no child now, so it's safe to create
+	   a frame.  */
+	stw	%rp, -20(%sp)
+	.cfi_offset 2, -20
+	stwm	%r3, 64(%sp)
+	.cfi_def_cfa_offset -64
+	.cfi_offset 3, 0
+	stw	%sp, -4(%sp)
+
+	sub	%r0,%ret0,%r3
+	SYSCALL_ERROR_HANDLER
+	/* Restore the PIC register (in delay slot) on error */
+#ifdef __PIC__
+	copy	%r25, %r19    /* parent */
+#else
+	nop
+#endif
+	/* Write syscall return into errno location */
+	stw	%r3, 0(%ret0)
+	ldw	-84(%sp), %rp
+	bv	%r0(%rp)
+	ldwm	-64(%sp), %r3
+
+PSEUDO_END (__vfork)
+libc_hidden_def(vfork)
+
+weak_alias (__vfork, vfork)