system/libucontext: Amend PowerPC patch (thanks koorogi!)

4 files changed, 586 insertions, 441 deletions

diff --git a/system/libucontext/APKBUILD b/system/libucontext/APKBUILD
index f152933a5..05950ae27 100644
--- a/system/libucontext/APKBUILD
+++ b/system/libucontext/APKBUILD
@@ -1,7 +1,7 @@
 # Maintainer: 
 pkgname=libucontext
 pkgver=0.1.3
-pkgrel=1
+pkgrel=2
 pkgdesc="ucontext function implementations"
 url="https://git.dereferenced.org/kaniini/libucontext/"
 arch="all"
@@ -9,8 +9,7 @@ license="ISC"
 depends=""
 subpackages="$pkgname-dev"
 source="https://distfiles.dereferenced.org/libucontext/libucontext-$pkgver.tar.xz
-	ppc64-assembly.patch
-	ppc64-stack-layout.patch
+	powerpc.patch
 	"
 
 case "$CTARGET_ARCH" in
@@ -36,5 +35,4 @@ package() {
 }
 
 sha512sums="9e0694c09f159de714b655f6a4201a05c8d1871ee7376bb6bf824206b45475cfbd8269ca1caa75b9c322624d9f77d3fc3f938228a4bdd267a5ddceb57ca5c1ab  libucontext-0.1.3.tar.xz
-dbb7599fe5cc1e470d944bf741c393c13e684d6c27bd794ec380a05ba1ba045597b102903a1ac9bf586a508941440373c2d29fad1d7372ee8c72ffb7f0e11f75  ppc64-assembly.patch
-d6219487a5aa456726a01a5a6a39c3a7f29bc24a66f2fc77ff7f852e1b45ffe64854ad92cafad3cc03d3b52bd77dce786ef125e3e88ddb0398833a560afb5211  ppc64-stack-layout.patch"
+22627fc66e57f64c24a8fb0d6e64fda8abfc4f72cc7a9b3d4f06cdb2b406adacd3d1b7eaa0321133959557ed4ee6856bdf5aee764f3b90981ec5b41cc1e5cd91  powerpc.patch"
diff --git a/system/libucontext/powerpc.patch b/system/libucontext/powerpc.patch
new file mode 100644
index 000000000..e6df4cf25
--- /dev/null
+++ b/system/libucontext/powerpc.patch
@@ -0,0 +1,583 @@
+From 2610c7faa7b9c4114d53bb659264a6be238cd2a3 Mon Sep 17 00:00:00 2001
+From: Bobby Bingham <koorogi@koorogi.info>
+Date: Sat, 23 Feb 2019 17:12:37 -0600
+Subject: [PATCH] ppc32/64: rewrite get/set/swapcontext in assembly
+
+getcontext cannot be correctly implemented in C.
+
+If this calls another function, as it does to call syscall, it needs to
+first spill its return address to the stack.  If, after getcontext returns,
+its caller then calls other functions, this saved return address can be
+clobbered.  When the context saved by getcontext is later restored, the
+(now clobbered) return address will be reloaded from the stack, and the
+second return from getcontext will return to the wrong location.
+
+Because the powerpc swapcontext syscall allows either the old context or
+new context pointers to be null, it is usable for implementing all of
+get/set/swapcontext.
+
+We therefore rewrite swapcontext in assembly, and get/setcontext as simple
+assembly function wrappers around swapcontext.
+
+The one piece we keep in C is the code to check the return value of the
+system call and to set errno.  This code was actually unnecessary before --
+libc does this within syscall.  However, now that the system call is made
+directly in assembly, bypassing libc, it is truly necessary.  Because errno
+is thread-local and the details of how to set it can vary by libc, this
+code remains written in C.
+---
+ Makefile                                      | 10 +----
+ README.md                                     |  2 +-
+ arch/ppc/getcontext.S                         | 20 +++++++++
+ arch/ppc/{getcontext.c => retfromsyscall.c}   | 30 +++----------
+ arch/ppc/setcontext.S                         | 21 +++++++++
+ arch/ppc/setcontext.c                         | 45 -------------------
+ arch/ppc/swapcontext.S                        | 23 ++++++++++
+ arch/ppc/swapcontext.c                        | 45 -------------------
+ arch/ppc64/getcontext.S                       | 25 +++++++++++
+ arch/ppc64/{getcontext.c => retfromsyscall.c} | 30 +++----------
+ arch/ppc64/setcontext.S                       | 26 +++++++++++
+ arch/ppc64/setcontext.c                       | 45 -------------------
+ arch/ppc64/swapcontext.S                      | 28 ++++++++++++
+ arch/ppc64/swapcontext.c                      | 45 -------------------
+ 14 files changed, 156 insertions(+), 239 deletions(-)
+ create mode 100644 arch/ppc/getcontext.S
+ rename arch/ppc/{getcontext.c => retfromsyscall.c} (53%)
+ create mode 100644 arch/ppc/setcontext.S
+ delete mode 100644 arch/ppc/setcontext.c
+ create mode 100644 arch/ppc/swapcontext.S
+ delete mode 100644 arch/ppc/swapcontext.c
+ create mode 100644 arch/ppc64/getcontext.S
+ rename arch/ppc64/{getcontext.c => retfromsyscall.c} (53%)
+ create mode 100644 arch/ppc64/setcontext.S
+ delete mode 100644 arch/ppc64/setcontext.c
+ create mode 100644 arch/ppc64/swapcontext.S
+ delete mode 100644 arch/ppc64/swapcontext.c
+
+diff --git a/Makefile b/Makefile
+index 51365a3..d6ff1b0 100644
+--- a/Makefile
++++ b/Makefile
+@@ -2,14 +2,8 @@ ARCH := $(shell uname -m)
+ 
+ CFLAGS = -ggdb3 -O2 -Wall -Iarch/${ARCH}
+ 
+-LIBUCONTEXT_C_SRC = \
+-	arch/${ARCH}/makecontext.c
+-
+-LIBUCONTEXT_S_SRC = \
+-	arch/${ARCH}/getcontext.S \
+-	arch/${ARCH}/setcontext.S \
+-	arch/${ARCH}/swapcontext.S \
+-	arch/${ARCH}/startcontext.S
++LIBUCONTEXT_C_SRC = $(wildcard arch/${ARCH}/*.c)
++LIBUCONTEXT_S_SRC = $(wildcard arch/${ARCH}/*.S)
+ 
+ LIBUCONTEXT_OBJ = ${LIBUCONTEXT_C_SRC:.c=.o} ${LIBUCONTEXT_S_SRC:.S=.o}
+ LIBUCONTEXT_SOVERSION = 0
+diff --git a/README.md b/README.md
+index 6bd4493..27d3d0b 100644
+--- a/README.md
++++ b/README.md
+@@ -19,7 +19,7 @@ Right now these archs are supported and should work on bare metal:
+  * aarch64
+  * s390x
+ 
+-These archs require kernel assistance and use a syscall (the only assembly is the trampoline):
++These archs require kernel assistance and use a syscall:
+ 
+  * ppc
+  * ppc64 (ELFv2 ABI spec only, ELFv1 not supported)
+diff --git a/arch/ppc/getcontext.S b/arch/ppc/getcontext.S
+new file mode 100644
+index 0000000..beffaf5
+--- /dev/null
++++ b/arch/ppc/getcontext.S
+@@ -0,0 +1,20 @@
++/*
++ * Copyright (c) 2019 Bobby Bingham <koorogi@koorogi.info>
++ *
++ * Permission to use, copy, modify, and/or distribute this software for any
++ * purpose with or without fee is hereby granted, provided that the above
++ * copyright notice and this permission notice appear in all copies.
++ *
++ * This software is provided 'as is' and without any warranty, express or
++ * implied.  In no event shall the authors be liable for any damages arising
++ * from the use of this software.
++ */
++
++.global __getcontext
++.hidden __swapcontext
++__getcontext:
++	li 4, 0
++	b __swapcontext@local
++
++.weak getcontext
++getcontext = __getcontext
+diff --git a/arch/ppc/getcontext.c b/arch/ppc/retfromsyscall.c
+similarity index 53%
+rename from arch/ppc/getcontext.c
+rename to arch/ppc/retfromsyscall.c
+index 5da9dfb..3ad43c0 100644
+--- a/arch/ppc/getcontext.c
++++ b/arch/ppc/retfromsyscall.c
+@@ -1,5 +1,6 @@
+ /*
+  * Copyright (c) 2018 William Pitcock <nenolod@dereferenced.org>
++ * Copyright (c) 2019 Bobby Bingham <koorogi@koorogi.info>
+  *
+  * Permission to use, copy, modify, and/or distribute this software for any
+  * purpose with or without fee is hereby granted, provided that the above
+@@ -10,36 +11,15 @@
+  * from the use of this software.
+  */
+ 
+-#define _GNU_SOURCE
+-#include <stddef.h>
+-#include <stdarg.h>
+-#include <signal.h>
+-#include <string.h>
+-#include <stdint.h>
+ #include <errno.h>
+-#include <unistd.h>
+-#include <sys/syscall.h>
+ 
+-
+-int
+-__getcontext(ucontext_t *ucp)
++__attribute__ ((visibility ("hidden")))
++int __retfromsyscall(long retval)
+ {
+-#ifdef SYS_swapcontext
+-	int r;
+-
+-	r = syscall(SYS_swapcontext, ucp, NULL, sizeof(ucontext_t));
+-	if (r < 0)
+-	{
+-		errno = -r;
++	if (retval < 0) {
++		errno = -retval;
+ 		return -1;
+ 	}
+-
+ 	return 0;
+-#else
+-	errno = ENOSYS;
+-	return -1;
+-#endif
+ }
+ 
+-
+-extern __typeof(__getcontext) getcontext __attribute__((weak, __alias__("__getcontext")));
+diff --git a/arch/ppc/setcontext.S b/arch/ppc/setcontext.S
+new file mode 100644
+index 0000000..89e6de0
+--- /dev/null
++++ b/arch/ppc/setcontext.S
+@@ -0,0 +1,21 @@
++/*
++ * Copyright (c) 2019 Bobby Bingham <koorogi@koorogi.info>
++ *
++ * Permission to use, copy, modify, and/or distribute this software for any
++ * purpose with or without fee is hereby granted, provided that the above
++ * copyright notice and this permission notice appear in all copies.
++ *
++ * This software is provided 'as is' and without any warranty, express or
++ * implied.  In no event shall the authors be liable for any damages arising
++ * from the use of this software.
++ */
++
++.global __setcontext
++.hidden __swapcontext
++__setcontext:
++	mr 4, 3
++	li 3, 0
++	b __swapcontext@local
++
++.weak setcontext
++setcontext = __setcontext
+diff --git a/arch/ppc/setcontext.c b/arch/ppc/setcontext.c
+deleted file mode 100644
+index 59c65b4..0000000
+--- a/arch/ppc/setcontext.c
++++ /dev/null
+@@ -1,45 +0,0 @@
+-/*
+- * Copyright (c) 2018 William Pitcock <nenolod@dereferenced.org>
+- *
+- * Permission to use, copy, modify, and/or distribute this software for any
+- * purpose with or without fee is hereby granted, provided that the above
+- * copyright notice and this permission notice appear in all copies.
+- *
+- * This software is provided 'as is' and without any warranty, express or
+- * implied.  In no event shall the authors be liable for any damages arising
+- * from the use of this software.
+- */
+-
+-#define _GNU_SOURCE
+-#include <stddef.h>
+-#include <stdarg.h>
+-#include <signal.h>
+-#include <string.h>
+-#include <stdint.h>
+-#include <errno.h>
+-#include <unistd.h>
+-#include <sys/syscall.h>
+-
+-
+-int
+-__setcontext(const ucontext_t *ucp)
+-{
+-#ifdef SYS_swapcontext
+-	int r;
+-
+-	r = syscall(SYS_swapcontext, NULL, (void *) ucp, sizeof(ucontext_t));
+-	if (r < 0)
+-	{
+-		errno = -r;
+-		return -1;
+-	}
+-
+-	return r;
+-#else
+-	errno = ENOSYS;
+-	return -1;
+-#endif
+-}
+-
+-
+-extern __typeof(__setcontext) setcontext __attribute__((weak, __alias__("__setcontext")));
+diff --git a/arch/ppc/swapcontext.S b/arch/ppc/swapcontext.S
+new file mode 100644
+index 0000000..24b6655
+--- /dev/null
++++ b/arch/ppc/swapcontext.S
+@@ -0,0 +1,23 @@
++/*
++ * Copyright (c) 2019 Bobby Bingham <koorogi@koorogi.info>
++ *
++ * Permission to use, copy, modify, and/or distribute this software for any
++ * purpose with or without fee is hereby granted, provided that the above
++ * copyright notice and this permission notice appear in all copies.
++ *
++ * This software is provided 'as is' and without any warranty, express or
++ * implied.  In no event shall the authors be liable for any damages arising
++ * from the use of this software.
++ */
++
++.global __swapcontext
++__swapcontext:
++	li 0, 249     # SYS_swapcontext
++	li 5, 1184    # sizeof(ucontext_t)
++	sc
++
++.hidden __retfromsyscall
++	b __retfromsyscall@local
++
++.weak swapcontext
++swapcontext = __swapcontext
+diff --git a/arch/ppc/swapcontext.c b/arch/ppc/swapcontext.c
+deleted file mode 100644
+index af14bc2..0000000
+--- a/arch/ppc/swapcontext.c
++++ /dev/null
+@@ -1,45 +0,0 @@
+-/*
+- * Copyright (c) 2018 William Pitcock <nenolod@dereferenced.org>
+- *
+- * Permission to use, copy, modify, and/or distribute this software for any
+- * purpose with or without fee is hereby granted, provided that the above
+- * copyright notice and this permission notice appear in all copies.
+- *
+- * This software is provided 'as is' and without any warranty, express or
+- * implied.  In no event shall the authors be liable for any damages arising
+- * from the use of this software.
+- */
+-
+-#define _GNU_SOURCE
+-#include <stddef.h>
+-#include <stdarg.h>
+-#include <signal.h>
+-#include <string.h>
+-#include <stdint.h>
+-#include <errno.h>
+-#include <unistd.h>
+-#include <sys/syscall.h>
+-
+-
+-int
+-__swapcontext(ucontext_t *oucp, const ucontext_t *ucp)
+-{
+-#ifdef SYS_swapcontext
+-	int r;
+-
+-	r = syscall(SYS_swapcontext, oucp, ucp, sizeof(ucontext_t));
+-	if (r < 0)
+-	{
+-		errno = -r;
+-		return -1;
+-	}
+-
+-	return r;
+-#else
+-	errno = ENOSYS;
+-	return -1;
+-#endif
+-}
+-
+-
+-extern __typeof(__swapcontext) swapcontext __attribute__((weak, __alias__("__swapcontext")));
+diff --git a/arch/ppc64/getcontext.S b/arch/ppc64/getcontext.S
+new file mode 100644
+index 0000000..935edd2
+--- /dev/null
++++ b/arch/ppc64/getcontext.S
+@@ -0,0 +1,25 @@
++/*
++ * Copyright (c) 2019 Bobby Bingham <koorogi@koorogi.info>
++ *
++ * Permission to use, copy, modify, and/or distribute this software for any
++ * purpose with or without fee is hereby granted, provided that the above
++ * copyright notice and this permission notice appear in all copies.
++ *
++ * This software is provided 'as is' and without any warranty, express or
++ * implied.  In no event shall the authors be liable for any damages arising
++ * from the use of this software.
++ */
++
++.global __getcontext
++.hidden __swapcontext
++__getcontext:
++	addis 2, 12, .TOC.-__getcontext@ha
++	addi  2, 12, .TOC.-__getcontext@l
++
++	.localentry __getcontext,.-__getcontext
++
++	li 4, 0
++	b __swapcontext
++
++.weak getcontext
++getcontext = __getcontext
+diff --git a/arch/ppc64/getcontext.c b/arch/ppc64/retfromsyscall.c
+similarity index 53%
+rename from arch/ppc64/getcontext.c
+rename to arch/ppc64/retfromsyscall.c
+index 5da9dfb..3ad43c0 100644
+--- a/arch/ppc64/getcontext.c
++++ b/arch/ppc64/retfromsyscall.c
+@@ -1,5 +1,6 @@
+ /*
+  * Copyright (c) 2018 William Pitcock <nenolod@dereferenced.org>
++ * Copyright (c) 2019 Bobby Bingham <koorogi@koorogi.info>
+  *
+  * Permission to use, copy, modify, and/or distribute this software for any
+  * purpose with or without fee is hereby granted, provided that the above
+@@ -10,36 +11,15 @@
+  * from the use of this software.
+  */
+ 
+-#define _GNU_SOURCE
+-#include <stddef.h>
+-#include <stdarg.h>
+-#include <signal.h>
+-#include <string.h>
+-#include <stdint.h>
+ #include <errno.h>
+-#include <unistd.h>
+-#include <sys/syscall.h>
+ 
+-
+-int
+-__getcontext(ucontext_t *ucp)
++__attribute__ ((visibility ("hidden")))
++int __retfromsyscall(long retval)
+ {
+-#ifdef SYS_swapcontext
+-	int r;
+-
+-	r = syscall(SYS_swapcontext, ucp, NULL, sizeof(ucontext_t));
+-	if (r < 0)
+-	{
+-		errno = -r;
++	if (retval < 0) {
++		errno = -retval;
+ 		return -1;
+ 	}
+-
+ 	return 0;
+-#else
+-	errno = ENOSYS;
+-	return -1;
+-#endif
+ }
+ 
+-
+-extern __typeof(__getcontext) getcontext __attribute__((weak, __alias__("__getcontext")));
+diff --git a/arch/ppc64/setcontext.S b/arch/ppc64/setcontext.S
+new file mode 100644
+index 0000000..5a0cde3
+--- /dev/null
++++ b/arch/ppc64/setcontext.S
+@@ -0,0 +1,26 @@
++/*
++ * Copyright (c) 2019 Bobby Bingham <koorogi@koorogi.info>
++ *
++ * Permission to use, copy, modify, and/or distribute this software for any
++ * purpose with or without fee is hereby granted, provided that the above
++ * copyright notice and this permission notice appear in all copies.
++ *
++ * This software is provided 'as is' and without any warranty, express or
++ * implied.  In no event shall the authors be liable for any damages arising
++ * from the use of this software.
++ */
++
++.global __setcontext
++.hidden __swapcontext
++__setcontext:
++	addis 2, 12, .TOC.-__setcontext@ha
++	addi  2, 12, .TOC.-__setcontext@l
++
++	.localentry __setcontext,.-__setcontext
++
++	mr 4, 3
++	li 3, 0
++	b __swapcontext
++
++.weak setcontext
++setcontext = __setcontext
+diff --git a/arch/ppc64/setcontext.c b/arch/ppc64/setcontext.c
+deleted file mode 100644
+index 59c65b4..0000000
+--- a/arch/ppc64/setcontext.c
++++ /dev/null
+@@ -1,45 +0,0 @@
+-/*
+- * Copyright (c) 2018 William Pitcock <nenolod@dereferenced.org>
+- *
+- * Permission to use, copy, modify, and/or distribute this software for any
+- * purpose with or without fee is hereby granted, provided that the above
+- * copyright notice and this permission notice appear in all copies.
+- *
+- * This software is provided 'as is' and without any warranty, express or
+- * implied.  In no event shall the authors be liable for any damages arising
+- * from the use of this software.
+- */
+-
+-#define _GNU_SOURCE
+-#include <stddef.h>
+-#include <stdarg.h>
+-#include <signal.h>
+-#include <string.h>
+-#include <stdint.h>
+-#include <errno.h>
+-#include <unistd.h>
+-#include <sys/syscall.h>
+-
+-
+-int
+-__setcontext(const ucontext_t *ucp)
+-{
+-#ifdef SYS_swapcontext
+-	int r;
+-
+-	r = syscall(SYS_swapcontext, NULL, (void *) ucp, sizeof(ucontext_t));
+-	if (r < 0)
+-	{
+-		errno = -r;
+-		return -1;
+-	}
+-
+-	return r;
+-#else
+-	errno = ENOSYS;
+-	return -1;
+-#endif
+-}
+-
+-
+-extern __typeof(__setcontext) setcontext __attribute__((weak, __alias__("__setcontext")));
+diff --git a/arch/ppc64/swapcontext.S b/arch/ppc64/swapcontext.S
+new file mode 100644
+index 0000000..982537a
+--- /dev/null
++++ b/arch/ppc64/swapcontext.S
+@@ -0,0 +1,28 @@
++/*
++ * Copyright (c) 2019 Bobby Bingham <koorogi@koorogi.info>
++ *
++ * Permission to use, copy, modify, and/or distribute this software for any
++ * purpose with or without fee is hereby granted, provided that the above
++ * copyright notice and this permission notice appear in all copies.
++ *
++ * This software is provided 'as is' and without any warranty, express or
++ * implied.  In no event shall the authors be liable for any damages arising
++ * from the use of this software.
++ */
++
++.global __swapcontext
++__swapcontext:
++	addis 2, 12, .TOC.-__swapcontext@ha
++	addi  2, 12, .TOC.-__swapcontext@l
++
++	.localentry __swapcontext,.-__swapcontext
++
++	li 0, 249     # SYS_swapcontext
++	li 5, 1696    # sizeof(ucontext_t)
++	sc
++
++.hidden __retfromsyscall
++	b __retfromsyscall
++
++.weak swapcontext
++swapcontext = __swapcontext
+diff --git a/arch/ppc64/swapcontext.c b/arch/ppc64/swapcontext.c
+deleted file mode 100644
+index af14bc2..0000000
+--- a/arch/ppc64/swapcontext.c
++++ /dev/null
+@@ -1,45 +0,0 @@
+-/*
+- * Copyright (c) 2018 William Pitcock <nenolod@dereferenced.org>
+- *
+- * Permission to use, copy, modify, and/or distribute this software for any
+- * purpose with or without fee is hereby granted, provided that the above
+- * copyright notice and this permission notice appear in all copies.
+- *
+- * This software is provided 'as is' and without any warranty, express or
+- * implied.  In no event shall the authors be liable for any damages arising
+- * from the use of this software.
+- */
+-
+-#define _GNU_SOURCE
+-#include <stddef.h>
+-#include <stdarg.h>
+-#include <signal.h>
+-#include <string.h>
+-#include <stdint.h>
+-#include <errno.h>
+-#include <unistd.h>
+-#include <sys/syscall.h>
+-
+-
+-int
+-__swapcontext(ucontext_t *oucp, const ucontext_t *ucp)
+-{
+-#ifdef SYS_swapcontext
+-	int r;
+-
+-	r = syscall(SYS_swapcontext, oucp, ucp, sizeof(ucontext_t));
+-	if (r < 0)
+-	{
+-		errno = -r;
+-		return -1;
+-	}
+-
+-	return r;
+-#else
+-	errno = ENOSYS;
+-	return -1;
+-#endif
+-}
+-
+-
+-extern __typeof(__swapcontext) swapcontext __attribute__((weak, __alias__("__swapcontext")));
diff --git a/system/libucontext/ppc64-assembly.patch b/system/libucontext/ppc64-assembly.patch
deleted file mode 100644
index 66fb3104d..000000000
--- a/system/libucontext/ppc64-assembly.patch
+++ /dev/null
@@ -1,331 +0,0 @@
-From 7b864e86e3e8e64fe69363137384ee9b858fe78d Mon Sep 17 00:00:00 2001
-From: Bobby Bingham <koorogi@koorogi.info>
-Date: Sat, 23 Feb 2019 17:12:37 -0600
-Subject: [PATCH 2/3] ppc64: rewrite get/set/swapcontext in assembly
-
-If getcontext makes any function call, which it does to call syscall, then
-it must spill its return address to the stack.  After it returns to its
-caller, that return address can be clobbered.  When setcontext is called
-to resume this saved context, the correct return address is not available.
----
- Makefile                    | 10 ++-------
- arch/ppc64/getcontext.S     | 25 +++++++++++++++++++++
- arch/ppc64/getcontext.c     | 45 -------------------------------------
- arch/ppc64/retfromsyscall.c | 24 ++++++++++++++++++++
- arch/ppc64/setcontext.S     | 26 +++++++++++++++++++++
- arch/ppc64/setcontext.c     | 45 -------------------------------------
- arch/ppc64/swapcontext.S    | 28 +++++++++++++++++++++++
- arch/ppc64/swapcontext.c    | 45 -------------------------------------
- 8 files changed, 105 insertions(+), 143 deletions(-)
- create mode 100644 arch/ppc64/getcontext.S
- delete mode 100644 arch/ppc64/getcontext.c
- create mode 100644 arch/ppc64/retfromsyscall.c
- create mode 100644 arch/ppc64/setcontext.S
- delete mode 100644 arch/ppc64/setcontext.c
- create mode 100644 arch/ppc64/swapcontext.S
- delete mode 100644 arch/ppc64/swapcontext.c
-
-diff --git a/Makefile b/Makefile
-index 51365a3..d6ff1b0 100644
---- a/Makefile
-+++ b/Makefile
-@@ -2,14 +2,8 @@ ARCH := $(shell uname -m)
- 
- CFLAGS = -ggdb3 -O2 -Wall -Iarch/${ARCH}
- 
--LIBUCONTEXT_C_SRC = \
--	arch/${ARCH}/makecontext.c
--
--LIBUCONTEXT_S_SRC = \
--	arch/${ARCH}/getcontext.S \
--	arch/${ARCH}/setcontext.S \
--	arch/${ARCH}/swapcontext.S \
--	arch/${ARCH}/startcontext.S
-+LIBUCONTEXT_C_SRC = $(wildcard arch/${ARCH}/*.c)
-+LIBUCONTEXT_S_SRC = $(wildcard arch/${ARCH}/*.S)
- 
- LIBUCONTEXT_OBJ = ${LIBUCONTEXT_C_SRC:.c=.o} ${LIBUCONTEXT_S_SRC:.S=.o}
- LIBUCONTEXT_SOVERSION = 0
-diff --git a/arch/ppc64/getcontext.S b/arch/ppc64/getcontext.S
-new file mode 100644
-index 0000000..935edd2
---- /dev/null
-+++ b/arch/ppc64/getcontext.S
-@@ -0,0 +1,25 @@
-+/*
-+ * Copyright (c) 2019 Bobby Bingham <koorogi@koorogi.info>
-+ *
-+ * Permission to use, copy, modify, and/or distribute this software for any
-+ * purpose with or without fee is hereby granted, provided that the above
-+ * copyright notice and this permission notice appear in all copies.
-+ *
-+ * This software is provided 'as is' and without any warranty, express or
-+ * implied.  In no event shall the authors be liable for any damages arising
-+ * from the use of this software.
-+ */
-+
-+.global __getcontext
-+.hidden __swapcontext
-+__getcontext:
-+	addis 2, 12, .TOC.-__getcontext@ha
-+	addi  2, 12, .TOC.-__getcontext@l
-+
-+	.localentry __getcontext,.-__getcontext
-+
-+	li 4, 0
-+	b __swapcontext
-+
-+.weak getcontext
-+getcontext = __getcontext
-diff --git a/arch/ppc64/getcontext.c b/arch/ppc64/getcontext.c
-deleted file mode 100644
-index 5da9dfb..0000000
---- a/arch/ppc64/getcontext.c
-+++ /dev/null
-@@ -1,45 +0,0 @@
--/*
-- * Copyright (c) 2018 William Pitcock <nenolod@dereferenced.org>
-- *
-- * Permission to use, copy, modify, and/or distribute this software for any
-- * purpose with or without fee is hereby granted, provided that the above
-- * copyright notice and this permission notice appear in all copies.
-- *
-- * This software is provided 'as is' and without any warranty, express or
-- * implied.  In no event shall the authors be liable for any damages arising
-- * from the use of this software.
-- */
--
--#define _GNU_SOURCE
--#include <stddef.h>
--#include <stdarg.h>
--#include <signal.h>
--#include <string.h>
--#include <stdint.h>
--#include <errno.h>
--#include <unistd.h>
--#include <sys/syscall.h>
--
--
--int
--__getcontext(ucontext_t *ucp)
--{
--#ifdef SYS_swapcontext
--	int r;
--
--	r = syscall(SYS_swapcontext, ucp, NULL, sizeof(ucontext_t));
--	if (r < 0)
--	{
--		errno = -r;
--		return -1;
--	}
--
--	return 0;
--#else
--	errno = ENOSYS;
--	return -1;
--#endif
--}
--
--
--extern __typeof(__getcontext) getcontext __attribute__((weak, __alias__("__getcontext")));
-diff --git a/arch/ppc64/retfromsyscall.c b/arch/ppc64/retfromsyscall.c
-new file mode 100644
-index 0000000..22c5134
---- /dev/null
-+++ b/arch/ppc64/retfromsyscall.c
-@@ -0,0 +1,24 @@
-+/*
-+ * Copyright (c) 2019 Bobby Bingham <koorogi@koorogi.info>
-+ *
-+ * Permission to use, copy, modify, and/or distribute this software for any
-+ * purpose with or without fee is hereby granted, provided that the above
-+ * copyright notice and this permission notice appear in all copies.
-+ *
-+ * This software is provided 'as is' and without any warranty, express or
-+ * implied.  In no event shall the authors be liable for any damages arising
-+ * from the use of this software.
-+ */
-+
-+#include <errno.h>
-+
-+__attribute__ ((visibility ("hidden")))
-+int __retfromsyscall(long retval)
-+{
-+	if (retval < 0) {
-+		errno = -retval;
-+		return -1;
-+	}
-+	return 0;
-+}
-+
-diff --git a/arch/ppc64/setcontext.S b/arch/ppc64/setcontext.S
-new file mode 100644
-index 0000000..5a0cde3
---- /dev/null
-+++ b/arch/ppc64/setcontext.S
-@@ -0,0 +1,26 @@
-+/*
-+ * Copyright (c) 2019 Bobby Bingham <koorogi@koorogi.info>
-+ *
-+ * Permission to use, copy, modify, and/or distribute this software for any
-+ * purpose with or without fee is hereby granted, provided that the above
-+ * copyright notice and this permission notice appear in all copies.
-+ *
-+ * This software is provided 'as is' and without any warranty, express or
-+ * implied.  In no event shall the authors be liable for any damages arising
-+ * from the use of this software.
-+ */
-+
-+.global __setcontext
-+.hidden __swapcontext
-+__setcontext:
-+	addis 2, 12, .TOC.-__setcontext@ha
-+	addi  2, 12, .TOC.-__setcontext@l
-+
-+	.localentry __setcontext,.-__setcontext
-+
-+	mr 4, 3
-+	li 3, 0
-+	b __swapcontext
-+
-+.weak setcontext
-+setcontext = __setcontext
-diff --git a/arch/ppc64/setcontext.c b/arch/ppc64/setcontext.c
-deleted file mode 100644
-index 59c65b4..0000000
---- a/arch/ppc64/setcontext.c
-+++ /dev/null
-@@ -1,45 +0,0 @@
--/*
-- * Copyright (c) 2018 William Pitcock <nenolod@dereferenced.org>
-- *
-- * Permission to use, copy, modify, and/or distribute this software for any
-- * purpose with or without fee is hereby granted, provided that the above
-- * copyright notice and this permission notice appear in all copies.
-- *
-- * This software is provided 'as is' and without any warranty, express or
-- * implied.  In no event shall the authors be liable for any damages arising
-- * from the use of this software.
-- */
--
--#define _GNU_SOURCE
--#include <stddef.h>
--#include <stdarg.h>
--#include <signal.h>
--#include <string.h>
--#include <stdint.h>
--#include <errno.h>
--#include <unistd.h>
--#include <sys/syscall.h>
--
--
--int
--__setcontext(const ucontext_t *ucp)
--{
--#ifdef SYS_swapcontext
--	int r;
--
--	r = syscall(SYS_swapcontext, NULL, (void *) ucp, sizeof(ucontext_t));
--	if (r < 0)
--	{
--		errno = -r;
--		return -1;
--	}
--
--	return r;
--#else
--	errno = ENOSYS;
--	return -1;
--#endif
--}
--
--
--extern __typeof(__setcontext) setcontext __attribute__((weak, __alias__("__setcontext")));
-diff --git a/arch/ppc64/swapcontext.S b/arch/ppc64/swapcontext.S
-new file mode 100644
-index 0000000..982537a
---- /dev/null
-+++ b/arch/ppc64/swapcontext.S
-@@ -0,0 +1,28 @@
-+/*
-+ * Copyright (c) 2019 Bobby Bingham <koorogi@koorogi.info>
-+ *
-+ * Permission to use, copy, modify, and/or distribute this software for any
-+ * purpose with or without fee is hereby granted, provided that the above
-+ * copyright notice and this permission notice appear in all copies.
-+ *
-+ * This software is provided 'as is' and without any warranty, express or
-+ * implied.  In no event shall the authors be liable for any damages arising
-+ * from the use of this software.
-+ */
-+
-+.global __swapcontext
-+__swapcontext:
-+	addis 2, 12, .TOC.-__swapcontext@ha
-+	addi  2, 12, .TOC.-__swapcontext@l
-+
-+	.localentry __swapcontext,.-__swapcontext
-+
-+	li 0, 249     # SYS_swapcontext
-+	li 5, 1696    # sizeof(ucontext_t)
-+	sc
-+
-+.hidden __retfromsyscall
-+	b __retfromsyscall
-+
-+.weak swapcontext
-+swapcontext = __swapcontext
-diff --git a/arch/ppc64/swapcontext.c b/arch/ppc64/swapcontext.c
-deleted file mode 100644
-index af14bc2..0000000
---- a/arch/ppc64/swapcontext.c
-+++ /dev/null
-@@ -1,45 +0,0 @@
--/*
-- * Copyright (c) 2018 William Pitcock <nenolod@dereferenced.org>
-- *
-- * Permission to use, copy, modify, and/or distribute this software for any
-- * purpose with or without fee is hereby granted, provided that the above
-- * copyright notice and this permission notice appear in all copies.
-- *
-- * This software is provided 'as is' and without any warranty, express or
-- * implied.  In no event shall the authors be liable for any damages arising
-- * from the use of this software.
-- */
--
--#define _GNU_SOURCE
--#include <stddef.h>
--#include <stdarg.h>
--#include <signal.h>
--#include <string.h>
--#include <stdint.h>
--#include <errno.h>
--#include <unistd.h>
--#include <sys/syscall.h>
--
--
--int
--__swapcontext(ucontext_t *oucp, const ucontext_t *ucp)
--{
--#ifdef SYS_swapcontext
--	int r;
--
--	r = syscall(SYS_swapcontext, oucp, ucp, sizeof(ucontext_t));
--	if (r < 0)
--	{
--		errno = -r;
--		return -1;
--	}
--
--	return r;
--#else
--	errno = ENOSYS;
--	return -1;
--#endif
--}
--
--
--extern __typeof(__swapcontext) swapcontext __attribute__((weak, __alias__("__swapcontext")));
--- 
-2.19.2
-
diff --git a/system/libucontext/ppc64-stack-layout.patch b/system/libucontext/ppc64-stack-layout.patch
deleted file mode 100644
index d030b61af..000000000
--- a/system/libucontext/ppc64-stack-layout.patch
+++ /dev/null
@@ -1,105 +0,0 @@
-From a17b01bc9df4004a1852ba272d452b0f46f5927c Mon Sep 17 00:00:00 2001
-From: Bobby Bingham <koorogi@koorogi.info>
-Date: Tue, 19 Feb 2019 06:27:28 +0000
-Subject: [PATCH 3/3] ppc64: fix stack frame layout
-
----
- arch/ppc64/makecontext.c | 48 +++++++++++++++++-----------------------
- 1 file changed, 20 insertions(+), 28 deletions(-)
-
-diff --git a/arch/ppc64/makecontext.c b/arch/ppc64/makecontext.c
-index 9d6b998..6d9841c 100644
---- a/arch/ppc64/makecontext.c
-+++ b/arch/ppc64/makecontext.c
-@@ -1,5 +1,6 @@
- /*
-  * Copyright (c) 2018 William Pitcock <nenolod@dereferenced.org>
-+ * Copyright (c) 2019 Bobby Bingham <koorogi@koorogi.info>
-  *
-  * Permission to use, copy, modify, and/or distribute this software for any
-  * purpose with or without fee is hereby granted, provided that the above
-@@ -11,32 +12,39 @@
-  */
- 
- #define _GNU_SOURCE
--#include <stddef.h>
- #include <stdarg.h>
- #include <signal.h>
--#include <string.h>
- #include <stdint.h>
- 
--
- #include "defs.h"
- 
- 
- extern void __start_context(void);
- 
- 
-+#define SAVEARG(i,val) \
-+	do { \
-+		*(i < 8 ? &ucp->uc_mcontext.gp_regs[3+i] : argp) = val; \
-+		argp++; \
-+	} while (0)
-+
- void
- __makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...)
- {
- 	greg_t *sp, *argp;
- 	va_list va;
--	int i;
--	unsigned int uc_link, stack_args;
-+	unsigned int stack_args;
-+
-+	/* We pass uc_link as an argument, so in total we have argc+1 args */
-+	stack_args = argc + 1;
- 
--	stack_args = argc > 8 ? argc - 8 : 0;
--	uc_link = stack_args + 1;
-+	/* We can pass 8 args before needing the stack.  If any arg is passed
-+	 * on the stack, then stack space must be reserved for all args, even
-+	 * though the first 8 don't need to be stored there */
-+	if (stack_args <= 8) stack_args = 0;
- 
- 	sp = (greg_t *) ((uintptr_t) ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size);
--	sp -= (uc_link + 1);
-+	sp -= stack_args + 4;
- 	sp = (greg_t *) (((uintptr_t) sp & -16L));
- 
- 	ucp->uc_mcontext.gp_regs[REG_NIP]   = (uintptr_t) func;
-@@ -45,29 +53,13 @@ __makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...)
- 	ucp->uc_mcontext.gp_regs[REG_ENTRY] = (uintptr_t) func;
- 	ucp->uc_mcontext.gp_regs[REG_R31]   = (uintptr_t) ucp->uc_link;
- 
--	sp[0] = (uintptr_t) &__start_context;
--	sp[uc_link] = (uintptr_t) ucp->uc_link;
--	argp = &sp[2];
-+	sp[0] = 0;
-+	argp = &sp[4];
- 
- 	va_start(va, argc);
- 
--	for (i = 0; i < argc; i++)
--		switch (i)
--		{
--		case 0:
--		case 1:
--		case 2:
--		case 3:
--		case 4:
--		case 5:
--		case 6:
--		case 7:
--			ucp->uc_mcontext.gp_regs[i + 3] = va_arg (va, greg_t);
--			break;
--		default:
--			*argp++ = va_arg (va, greg_t);
--			break;
--		}
-+	for (int i = 0; i < argc; i++) SAVEARG(i, va_arg(va, greg_t));
-+	SAVEARG(argc, (uintptr_t) ucp->uc_link);
- 
- 	va_end(va);
- }
--- 
-2.19.2
-