--- /dev/null
+/*
+ * Copyright (C) 2004 Jeff Dike (jdike@addtoit.com)
+ * Licensed under the GPL
+ */
+
+#include <stddef.h>
+#include <signal.h>
+#include <linux/compiler.h>
+#include <asm/unistd.h>
+#include "uml-config.h"
+#include "sysdep/sigcontext.h"
+#include "sysdep/faultinfo.h"
+#include "sysdep/stub.h"
+
+/* Copied from sys-x86_64/signal.c - Can't find an equivalent definition
+ * in the libc headers anywhere.
+ */
+struct rt_sigframe
+{
+ char *pretcode;
+ struct ucontext uc;
+ struct siginfo info;
+};
+
+/* Copied here from <linux/kernel.h> - we're userspace. */
+#define container_of(ptr, type, member) ({ \
+ const typeof( ((type *)0)->member ) *__mptr = (ptr); \
+ (type *)( (char *)__mptr - offsetof(type,member) );})
+
+void __attribute__ ((__section__ (".__syscall_stub")))
+stub_segv_handler(int sig)
+{
+ struct ucontext *uc;
+ int pid;
+
+ __asm__ __volatile__("movq %%rdx, %0" : "=g" (uc) :);
+ GET_FAULTINFO_FROM_SC(*((struct faultinfo *) UML_CONFIG_STUB_DATA),
+ &uc->uc_mcontext);
+
+ pid = stub_syscall0(__NR_getpid);
+ stub_syscall2(__NR_kill, pid, SIGUSR1);
+
+ /* sys_sigreturn expects that the stack pointer will be 8 bytes into
+ * the signal frame. So, we use the ucontext pointer, which we know
+ * already, to get the signal frame pointer, and add 8 to that.
+ */
+ __asm__ __volatile__("movq %0, %%rsp; movq %1, %%rax ; syscall": :
+ "g" ((unsigned long)
+ container_of(uc, struct rt_sigframe, uc) + 8),
+ "g" (__NR_rt_sigreturn));
+}