[PATCH] MIPS: Factor o32 specific code into signal_o32.c

From: Harvey Hunt
Date: Fri Jun 17 2016 - 11:04:00 EST

The commit ebb5e78cc634 ("MIPS: Initial implementation of a VDSO")
caused building a 64 bit kernel with support for n32 and not o32
to produce a build error:

arch/mips/kernel/signal32.c:415:11: error: âvdso_image_o32â undeclared here (not in a function)
.vdso = &vdso_image_o32,

Fix this by moving the o32 specific code into signal_o32.c and
updating the Makefile accordingly.

Signed-off-by: Harvey Hunt <harvey.hunt@xxxxxxxxxx>
Cc: Leonid Yegoshin <Leonid.Yegoshin@xxxxxxxxxx>
Cc: Alex Smith <alex@xxxxxxxxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
arch/mips/include/asm/signal.h | 2 +-
arch/mips/kernel/Makefile | 2 +-
arch/mips/kernel/signal32.c | 288 +----------------------------------------
arch/mips/kernel/signal_o32.c | 285 ++++++++++++++++++++++++++++++++++++++++
4 files changed, 293 insertions(+), 284 deletions(-)
create mode 100644 arch/mips/kernel/signal_o32.c

diff --git a/arch/mips/include/asm/signal.h b/arch/mips/include/asm/signal.h
index 2292373..77b3b95 100644
--- a/arch/mips/include/asm/signal.h
+++ b/arch/mips/include/asm/signal.h
@@ -11,7 +11,7 @@

#include <uapi/asm/signal.h>

-#ifdef CONFIG_MIPS32_COMPAT
+#ifdef CONFIG_MIPS32_O32
extern struct mips_abi mips_abi_32;

#define sig_uses_siginfo(ka, abi) \
diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile
index e6053d0..4a603a3 100644
--- a/arch/mips/kernel/Makefile
+++ b/arch/mips/kernel/Makefile
@@ -71,7 +71,7 @@ obj-$(CONFIG_32BIT) += scall32-o32.o
obj-$(CONFIG_64BIT) += scall64-64.o
obj-$(CONFIG_MIPS32_COMPAT) += linux32.o ptrace32.o signal32.o
obj-$(CONFIG_MIPS32_N32) += binfmt_elfn32.o scall64-n32.o signal_n32.o
-obj-$(CONFIG_MIPS32_O32) += binfmt_elfo32.o scall64-o32.o
+obj-$(CONFIG_MIPS32_O32) += binfmt_elfo32.o scall64-o32.o signal_o32.o

obj-$(CONFIG_KGDB) += kgdb.o
obj-$(CONFIG_PROC_FS) += proc.o
diff --git a/arch/mips/kernel/signal32.c b/arch/mips/kernel/signal32.c
index 78c8349..97b7c51 100644
--- a/arch/mips/kernel/signal32.c
+++ b/arch/mips/kernel/signal32.c
@@ -6,129 +6,26 @@
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright (C) 1994 - 2000, 2006 Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ * Copyright (C) 2016, Imagination Technologies Ltd.
*/
-#include <linux/cache.h>
-#include <linux/compat.h>
-#include <linux/sched.h>
-#include <linux/mm.h>
-#include <linux/smp.h>
+#include <linux/compiler.h>
+#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/signal.h>
#include <linux/syscalls.h>
-#include <linux/errno.h>
-#include <linux/wait.h>
-#include <linux/ptrace.h>
-#include <linux/suspend.h>
-#include <linux/compiler.h>
-#include <linux/uaccess.h>

-#include <asm/abi.h>
-#include <asm/asm.h>
+#include <asm/compat.h>
#include <asm/compat-signal.h>
-#include <linux/bitops.h>
-#include <asm/cacheflush.h>
-#include <asm/sim.h>
-#include <asm/ucontext.h>
-#include <asm/fpu.h>
-#include <asm/war.h>
-#include <asm/dsp.h>
+#include <asm/uaccess.h>
+#include <asm/unistd.h>

#include "signal-common.h"

-/*
- * Including <asm/unistd.h> would give use the 64-bit syscall numbers ...
- */
-#define __NR_O32_restart_syscall 4253
-
/* 32-bit compatibility types */

typedef unsigned int __sighandler32_t;
typedef void (*vfptr_t)(void);

-struct ucontext32 {
- u32 uc_flags;
- s32 uc_link;
- compat_stack_t uc_stack;
- struct sigcontext32 uc_mcontext;
- compat_sigset_t uc_sigmask; /* mask last for extensibility */
-};
-
-struct sigframe32 {
- u32 sf_ass[4]; /* argument save space for o32 */
- u32 sf_pad[2]; /* Was: signal trampoline */
- struct sigcontext32 sf_sc;
- compat_sigset_t sf_mask;
-};
-
-struct rt_sigframe32 {
- u32 rs_ass[4]; /* argument save space for o32 */
- u32 rs_pad[2]; /* Was: signal trampoline */
- compat_siginfo_t rs_info;
- struct ucontext32 rs_uc;
-};
-
-static int setup_sigcontext32(struct pt_regs *regs,
- struct sigcontext32 __user *sc)
-{
- int err = 0;
- int i;
-
- err |= __put_user(regs->cp0_epc, &sc->sc_pc);
-
- err |= __put_user(0, &sc->sc_regs[0]);
- for (i = 1; i < 32; i++)
- err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
-
- err |= __put_user(regs->hi, &sc->sc_mdhi);
- err |= __put_user(regs->lo, &sc->sc_mdlo);
- if (cpu_has_dsp) {
- err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
- err |= __put_user(mfhi1(), &sc->sc_hi1);
- err |= __put_user(mflo1(), &sc->sc_lo1);
- err |= __put_user(mfhi2(), &sc->sc_hi2);
- err |= __put_user(mflo2(), &sc->sc_lo2);
- err |= __put_user(mfhi3(), &sc->sc_hi3);
- err |= __put_user(mflo3(), &sc->sc_lo3);
- }
-
- /*
- * Save FPU state to signal context. Signal handler
- * will "inherit" current FPU state.
- */
- err |= protected_save_fp_context(sc);
-
- return err;
-}
-
-static int restore_sigcontext32(struct pt_regs *regs,
- struct sigcontext32 __user *sc)
-{
- int err = 0;
- s32 treg;
- int i;
-
- /* Always make any pending restarted system calls return -EINTR */
- current->restart_block.fn = do_no_restart_syscall;
-
- err |= __get_user(regs->cp0_epc, &sc->sc_pc);
- err |= __get_user(regs->hi, &sc->sc_mdhi);
- err |= __get_user(regs->lo, &sc->sc_mdlo);
- if (cpu_has_dsp) {
- err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
- err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
- err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
- err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
- err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
- err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
- err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
- }
-
- for (i = 1; i < 32; i++)
- err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
-
- return err ?: protected_restore_fp_context(sc);
-}
-
/*
* Atomically swap in the new signal mask, and wait for a signal.
*/
@@ -247,176 +144,3 @@ int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from)

return 0;
}
-
-asmlinkage void sys32_sigreturn(nabi_no_regargs struct pt_regs regs)
-{
- struct sigframe32 __user *frame;
- sigset_t blocked;
- int sig;
-
- frame = (struct sigframe32 __user *) regs.regs[29];
- if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
- goto badframe;
- if (__copy_conv_sigset_from_user(&blocked, &frame->sf_mask))
- goto badframe;
-
- set_current_blocked(&blocked);
-
- sig = restore_sigcontext32(&regs, &frame->sf_sc);
- if (sig < 0)
- goto badframe;
- else if (sig)
- force_sig(sig, current);
-
- /*
- * Don't let your children do this ...
- */
- __asm__ __volatile__(
- "move\t$29, %0\n\t"
- "j\tsyscall_exit"
- :/* no outputs */
- :"r" (&regs));
- /* Unreached */
-
-badframe:
- force_sig(SIGSEGV, current);
-}
-
-asmlinkage void sys32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
-{
- struct rt_sigframe32 __user *frame;
- sigset_t set;
- int sig;
-
- frame = (struct rt_sigframe32 __user *) regs.regs[29];
- if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
- goto badframe;
- if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask))
- goto badframe;
-
- set_current_blocked(&set);
-
- sig = restore_sigcontext32(&regs, &frame->rs_uc.uc_mcontext);
- if (sig < 0)
- goto badframe;
- else if (sig)
- force_sig(sig, current);
-
- if (compat_restore_altstack(&frame->rs_uc.uc_stack))
- goto badframe;
-
- /*
- * Don't let your children do this ...
- */
- __asm__ __volatile__(
- "move\t$29, %0\n\t"
- "j\tsyscall_exit"
- :/* no outputs */
- :"r" (&regs));
- /* Unreached */
-
-badframe:
- force_sig(SIGSEGV, current);
-}
-
-static int setup_frame_32(void *sig_return, struct ksignal *ksig,
- struct pt_regs *regs, sigset_t *set)
-{
- struct sigframe32 __user *frame;
- int err = 0;
-
- frame = get_sigframe(ksig, regs, sizeof(*frame));
- if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
- return -EFAULT;
-
- err |= setup_sigcontext32(regs, &frame->sf_sc);
- err |= __copy_conv_sigset_to_user(&frame->sf_mask, set);
-
- if (err)
- return -EFAULT;
-
- /*
- * Arguments to signal handler:
- *
- * a0 = signal number
- * a1 = 0 (should be cause)
- * a2 = pointer to struct sigcontext
- *
- * $25 and c0_epc point to the signal handler, $29 points to the
- * struct sigframe.
- */
- regs->regs[ 4] = ksig->sig;
- regs->regs[ 5] = 0;
- regs->regs[ 6] = (unsigned long) &frame->sf_sc;
- regs->regs[29] = (unsigned long) frame;
- regs->regs[31] = (unsigned long) sig_return;
- regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler;
-
- DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
- current->comm, current->pid,
- frame, regs->cp0_epc, regs->regs[31]);
-
- return 0;
-}
-
-static int setup_rt_frame_32(void *sig_return, struct ksignal *ksig,
- struct pt_regs *regs, sigset_t *set)
-{
- struct rt_sigframe32 __user *frame;
- int err = 0;
-
- frame = get_sigframe(ksig, regs, sizeof(*frame));
- if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
- return -EFAULT;
-
- /* Convert (siginfo_t -> compat_siginfo_t) and copy to user. */
- err |= copy_siginfo_to_user32(&frame->rs_info, &ksig->info);
-
- /* Create the ucontext. */
- err |= __put_user(0, &frame->rs_uc.uc_flags);
- err |= __put_user(0, &frame->rs_uc.uc_link);
- err |= __compat_save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]);
- err |= setup_sigcontext32(regs, &frame->rs_uc.uc_mcontext);
- err |= __copy_conv_sigset_to_user(&frame->rs_uc.uc_sigmask, set);
-
- if (err)
- return -EFAULT;
-
- /*
- * Arguments to signal handler:
- *
- * a0 = signal number
- * a1 = 0 (should be cause)
- * a2 = pointer to ucontext
- *
- * $25 and c0_epc point to the signal handler, $29 points to
- * the struct rt_sigframe32.
- */
- regs->regs[ 4] = ksig->sig;
- regs->regs[ 5] = (unsigned long) &frame->rs_info;
- regs->regs[ 6] = (unsigned long) &frame->rs_uc;
- regs->regs[29] = (unsigned long) frame;
- regs->regs[31] = (unsigned long) sig_return;
- regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler;
-
- DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
- current->comm, current->pid,
- frame, regs->cp0_epc, regs->regs[31]);
-
- return 0;
-}
-
-/*
- * o32 compatibility on 64-bit kernels, without DSP ASE
- */
-struct mips_abi mips_abi_32 = {
- .setup_frame = setup_frame_32,
- .setup_rt_frame = setup_rt_frame_32,
- .restart = __NR_O32_restart_syscall,
-
- .off_sc_fpregs = offsetof(struct sigcontext32, sc_fpregs),
- .off_sc_fpc_csr = offsetof(struct sigcontext32, sc_fpc_csr),
- .off_sc_used_math = offsetof(struct sigcontext32, sc_used_math),
-
- .vdso = &vdso_image_o32,
-};
diff --git a/arch/mips/kernel/signal_o32.c b/arch/mips/kernel/signal_o32.c
new file mode 100644
index 0000000..5e169fc
--- /dev/null
+++ b/arch/mips/kernel/signal_o32.c
@@ -0,0 +1,285 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ * Copyright (C) 1994 - 2000, 2006 Ralf Baechle
+ * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ * Copyright (C) 2016, Imagination Technologies Ltd.
+ */
+#include <linux/compiler.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/uaccess.h>
+
+#include <asm/abi.h>
+#include <asm/compat-signal.h>
+#include <asm/dsp.h>
+#include <asm/sim.h>
+#include <asm/unistd.h>
+
+#include "signal-common.h"
+
+/*
+ * Including <asm/unistd.h> would give use the 64-bit syscall numbers ...
+ */
+#define __NR_O32_restart_syscall 4253
+
+struct sigframe32 {
+ u32 sf_ass[4]; /* argument save space for o32 */
+ u32 sf_pad[2]; /* Was: signal trampoline */
+ struct sigcontext32 sf_sc;
+ compat_sigset_t sf_mask;
+};
+
+struct ucontext32 {
+ u32 uc_flags;
+ s32 uc_link;
+ compat_stack_t uc_stack;
+ struct sigcontext32 uc_mcontext;
+ compat_sigset_t uc_sigmask; /* mask last for extensibility */
+};
+
+struct rt_sigframe32 {
+ u32 rs_ass[4]; /* argument save space for o32 */
+ u32 rs_pad[2]; /* Was: signal trampoline */
+ compat_siginfo_t rs_info;
+ struct ucontext32 rs_uc;
+};
+
+static int setup_sigcontext32(struct pt_regs *regs,
+ struct sigcontext32 __user *sc)
+{
+ int err = 0;
+ int i;
+
+ err |= __put_user(regs->cp0_epc, &sc->sc_pc);
+
+ err |= __put_user(0, &sc->sc_regs[0]);
+ for (i = 1; i < 32; i++)
+ err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
+
+ err |= __put_user(regs->hi, &sc->sc_mdhi);
+ err |= __put_user(regs->lo, &sc->sc_mdlo);
+ if (cpu_has_dsp) {
+ err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
+ err |= __put_user(mfhi1(), &sc->sc_hi1);
+ err |= __put_user(mflo1(), &sc->sc_lo1);
+ err |= __put_user(mfhi2(), &sc->sc_hi2);
+ err |= __put_user(mflo2(), &sc->sc_lo2);
+ err |= __put_user(mfhi3(), &sc->sc_hi3);
+ err |= __put_user(mflo3(), &sc->sc_lo3);
+ }
+
+ /*
+ * Save FPU state to signal context. Signal handler
+ * will "inherit" current FPU state.
+ */
+ err |= protected_save_fp_context(sc);
+
+ return err;
+}
+
+static int restore_sigcontext32(struct pt_regs *regs,
+ struct sigcontext32 __user *sc)
+{
+ int err = 0;
+ s32 treg;
+ int i;
+
+ /* Always make any pending restarted system calls return -EINTR */
+ current->restart_block.fn = do_no_restart_syscall;
+
+ err |= __get_user(regs->cp0_epc, &sc->sc_pc);
+ err |= __get_user(regs->hi, &sc->sc_mdhi);
+ err |= __get_user(regs->lo, &sc->sc_mdlo);
+ if (cpu_has_dsp) {
+ err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
+ err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
+ err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
+ err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
+ err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
+ err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
+ err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
+ }
+
+ for (i = 1; i < 32; i++)
+ err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
+
+ return err ?: protected_restore_fp_context(sc);
+}
+
+static int setup_frame_32(void *sig_return, struct ksignal *ksig,
+ struct pt_regs *regs, sigset_t *set)
+{
+ struct sigframe32 __user *frame;
+ int err = 0;
+
+ frame = get_sigframe(ksig, regs, sizeof(*frame));
+ if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
+ return -EFAULT;
+
+ err |= setup_sigcontext32(regs, &frame->sf_sc);
+ err |= __copy_conv_sigset_to_user(&frame->sf_mask, set);
+
+ if (err)
+ return -EFAULT;
+
+ /*
+ * Arguments to signal handler:
+ *
+ * a0 = signal number
+ * a1 = 0 (should be cause)
+ * a2 = pointer to struct sigcontext
+ *
+ * $25 and c0_epc point to the signal handler, $29 points to the
+ * struct sigframe.
+ */
+ regs->regs[ 4] = ksig->sig;
+ regs->regs[ 5] = 0;
+ regs->regs[ 6] = (unsigned long) &frame->sf_sc;
+ regs->regs[29] = (unsigned long) frame;
+ regs->regs[31] = (unsigned long) sig_return;
+ regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler;
+
+ DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
+ current->comm, current->pid,
+ frame, regs->cp0_epc, regs->regs[31]);
+
+ return 0;
+}
+
+asmlinkage void sys32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
+{
+ struct rt_sigframe32 __user *frame;
+ sigset_t set;
+ int sig;
+
+ frame = (struct rt_sigframe32 __user *) regs.regs[29];
+ if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
+ goto badframe;
+ if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask))
+ goto badframe;
+
+ set_current_blocked(&set);
+
+ sig = restore_sigcontext32(&regs, &frame->rs_uc.uc_mcontext);
+ if (sig < 0)
+ goto badframe;
+ else if (sig)
+ force_sig(sig, current);
+
+ if (compat_restore_altstack(&frame->rs_uc.uc_stack))
+ goto badframe;
+
+ /*
+ * Don't let your children do this ...
+ */
+ __asm__ __volatile__(
+ "move\t$29, %0\n\t"
+ "j\tsyscall_exit"
+ :/* no outputs */
+ :"r" (&regs));
+ /* Unreached */
+
+badframe:
+ force_sig(SIGSEGV, current);
+}
+
+static int setup_rt_frame_32(void *sig_return, struct ksignal *ksig,
+ struct pt_regs *regs, sigset_t *set)
+{
+ struct rt_sigframe32 __user *frame;
+ int err = 0;
+
+ frame = get_sigframe(ksig, regs, sizeof(*frame));
+ if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
+ return -EFAULT;
+
+ /* Convert (siginfo_t -> compat_siginfo_t) and copy to user. */
+ err |= copy_siginfo_to_user32(&frame->rs_info, &ksig->info);
+
+ /* Create the ucontext. */
+ err |= __put_user(0, &frame->rs_uc.uc_flags);
+ err |= __put_user(0, &frame->rs_uc.uc_link);
+ err |= __compat_save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]);
+ err |= setup_sigcontext32(regs, &frame->rs_uc.uc_mcontext);
+ err |= __copy_conv_sigset_to_user(&frame->rs_uc.uc_sigmask, set);
+
+ if (err)
+ return -EFAULT;
+
+ /*
+ * Arguments to signal handler:
+ *
+ * a0 = signal number
+ * a1 = 0 (should be cause)
+ * a2 = pointer to ucontext
+ *
+ * $25 and c0_epc point to the signal handler, $29 points to
+ * the struct rt_sigframe32.
+ */
+ regs->regs[ 4] = ksig->sig;
+ regs->regs[ 5] = (unsigned long) &frame->rs_info;
+ regs->regs[ 6] = (unsigned long) &frame->rs_uc;
+ regs->regs[29] = (unsigned long) frame;
+ regs->regs[31] = (unsigned long) sig_return;
+ regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler;
+
+ DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
+ current->comm, current->pid,
+ frame, regs->cp0_epc, regs->regs[31]);
+
+ return 0;
+}
+
+/*
+ * o32 compatibility on 64-bit kernels, without DSP ASE
+ */
+struct mips_abi mips_abi_32 = {
+ .setup_frame = setup_frame_32,
+ .setup_rt_frame = setup_rt_frame_32,
+ .restart = __NR_O32_restart_syscall,
+
+ .off_sc_fpregs = offsetof(struct sigcontext32, sc_fpregs),
+ .off_sc_fpc_csr = offsetof(struct sigcontext32, sc_fpc_csr),
+ .off_sc_used_math = offsetof(struct sigcontext32, sc_used_math),
+
+ .vdso = &vdso_image_o32,
+};
+
+
+asmlinkage void sys32_sigreturn(nabi_no_regargs struct pt_regs regs)
+{
+ struct sigframe32 __user *frame;
+ sigset_t blocked;
+ int sig;
+
+ frame = (struct sigframe32 __user *) regs.regs[29];
+ if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
+ goto badframe;
+ if (__copy_conv_sigset_from_user(&blocked, &frame->sf_mask))
+ goto badframe;
+
+ set_current_blocked(&blocked);
+
+ sig = restore_sigcontext32(&regs, &frame->sf_sc);
+ if (sig < 0)
+ goto badframe;
+ else if (sig)
+ force_sig(sig, current);
+
+ /*
+ * Don't let your children do this ...
+ */
+ __asm__ __volatile__(
+ "move\t$29, %0\n\t"
+ "j\tsyscall_exit"
+ :/* no outputs */
+ :"r" (&regs));
+ /* Unreached */
+
+badframe:
+ force_sig(SIGSEGV, current);
+}
--
2.8.3