-/*
- * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+/*
+ * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ * Copyright 2003 PathScale, Inc.
* Licensed under the GPL
*/
-#include <stdio.h>
-#include <unistd.h>
-#include <signal.h>
-#include <sched.h>
-#include <errno.h>
-#include <stdarg.h>
-#include <stdlib.h>
-#include <setjmp.h>
-#include <sys/time.h>
-#include <sys/wait.h>
-#include <sys/mman.h>
-#include <asm/unistd.h>
-#include <asm/page.h>
-#include "user_util.h"
+#include <linux/stddef.h>
+#include <linux/err.h>
+#include <linux/hardirq.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/personality.h>
+#include <linux/proc_fs.h>
+#include <linux/ptrace.h>
+#include <linux/random.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/tick.h>
+#include <linux/threads.h>
+#include <asm/current.h>
+#include <asm/pgtable.h>
+#include <asm/uaccess.h>
+#include "as-layout.h"
#include "kern_util.h"
-#include "user.h"
-#include "process.h"
-#include "signal_kern.h"
-#include "signal_user.h"
-#include "sysdep/ptrace.h"
-#include "sysdep/sigcontext.h"
-#include "irq_user.h"
-#include "ptrace_user.h"
-#include "time_user.h"
-#include "init.h"
#include "os.h"
-#include "uml-config.h"
-#include "ptrace_user.h"
-#include "choose-mode.h"
-#include "mode.h"
-#ifdef UML_CONFIG_MODE_SKAS
#include "skas.h"
-#include "skas_ptrace.h"
-#include "registers.h"
-#endif
+#include "tlb.h"
+
+/*
+ * This is a per-cpu array. A processor only modifies its entry and it only
+ * cares about its entry, so it's OK if another processor is modifying its
+ * entry.
+ */
+struct cpu_task cpu_tasks[NR_CPUS] = { [0 ... NR_CPUS - 1] = { -1, NULL } };
-void init_new_thread_stack(void *sig_stack, void (*usr1_handler)(int))
+static inline int external_pid(void)
{
- int flags = 0, pages;
+ /* FIXME: Need to look up userspace_pid by cpu */
+ return userspace_pid[0];
+}
- if(sig_stack != NULL){
- pages = (1 << UML_CONFIG_KERNEL_STACK_ORDER);
- set_sigstack(sig_stack, pages * page_size());
- flags = SA_ONSTACK;
+int pid_to_processor_id(int pid)
+{
+ int i;
+
+ for (i = 0; i < ncpus; i++) {
+ if (cpu_tasks[i].pid == pid)
+ return i;
}
- if(usr1_handler) set_handler(SIGUSR1, usr1_handler, flags, -1);
+ return -1;
+}
+
+void free_stack(unsigned long stack, int order)
+{
+ free_pages(stack, order);
}
-void init_new_thread_signals(int altstack)
+unsigned long alloc_stack(int order, int atomic)
{
- int flags = altstack ? SA_ONSTACK : 0;
+ unsigned long page;
+ gfp_t flags = GFP_KERNEL;
- set_handler(SIGSEGV, (__sighandler_t) sig_handler, flags,
- SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
- set_handler(SIGTRAP, (__sighandler_t) sig_handler, flags,
- SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
- set_handler(SIGFPE, (__sighandler_t) sig_handler, flags,
- SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
- set_handler(SIGILL, (__sighandler_t) sig_handler, flags,
- SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
- set_handler(SIGBUS, (__sighandler_t) sig_handler, flags,
- SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
- set_handler(SIGUSR2, (__sighandler_t) sig_handler,
- flags, SIGUSR1, SIGIO, SIGWINCH, SIGALRM, SIGVTALRM, -1);
- signal(SIGHUP, SIG_IGN);
+ if (atomic)
+ flags = GFP_ATOMIC;
+ page = __get_free_pages(flags, order);
- init_irq_signals(altstack);
+ return page;
}
-struct tramp {
- int (*tramp)(void *);
- void *tramp_data;
- unsigned long temp_stack;
- int flags;
+int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
+{
int pid;
-};
-/* See above for why sigkill is here */
+ current->thread.request.u.thread.proc = fn;
+ current->thread.request.u.thread.arg = arg;
+ pid = do_fork(CLONE_VM | CLONE_UNTRACED | flags, 0,
+ ¤t->thread.regs, 0, NULL, NULL);
+ return pid;
+}
+
+static inline void set_current(struct task_struct *task)
+{
+ cpu_tasks[task_thread_info(task)->cpu] = ((struct cpu_task)
+ { external_pid(), task });
+}
-int sigkill = SIGKILL;
+extern void arch_switch_to(struct task_struct *to);
-int outer_tramp(void *arg)
+void *_switch_to(void *prev, void *next, void *last)
{
- struct tramp *t;
- int sig = sigkill;
+ struct task_struct *from = prev;
+ struct task_struct *to = next;
+
+ to->thread.prev_sched = from;
+ set_current(to);
+
+ do {
+ current->thread.saved_task = NULL;
+
+ switch_threads(&from->thread.switch_buf,
+ &to->thread.switch_buf);
+
+ arch_switch_to(current);
+
+ if (current->thread.saved_task)
+ show_regs(&(current->thread.regs));
+ to = current->thread.saved_task;
+ from = current;
+ } while (current->thread.saved_task);
+
+ return current->thread.prev_sched;
- t = arg;
- t->pid = clone(t->tramp, (void *) t->temp_stack + page_size()/2,
- t->flags, t->tramp_data);
- if(t->pid > 0) wait_for_stop(t->pid, SIGSTOP, PTRACE_CONT, NULL);
- kill(os_getpid(), sig);
- _exit(0);
}
-int start_fork_tramp(void *thread_arg, unsigned long temp_stack,
- int clone_flags, int (*tramp)(void *))
+void interrupt_end(void)
{
- struct tramp arg;
- unsigned long sp;
- int new_pid, status, err;
+ if (need_resched())
+ schedule();
+ if (test_tsk_thread_flag(current, TIF_SIGPENDING))
+ do_signal();
+}
- /* The trampoline will run on the temporary stack */
- sp = stack_sp(temp_stack);
+void exit_thread(void)
+{
+}
- clone_flags |= CLONE_FILES | SIGCHLD;
+void *get_current(void)
+{
+ return current;
+}
- arg.tramp = tramp;
- arg.tramp_data = thread_arg;
- arg.temp_stack = temp_stack;
- arg.flags = clone_flags;
+/*
+ * This is called magically, by its address being stuffed in a jmp_buf
+ * and being longjmp-d to.
+ */
+void new_thread_handler(void)
+{
+ int (*fn)(void *), n;
+ void *arg;
+
+ if (current->thread.prev_sched != NULL)
+ schedule_tail(current->thread.prev_sched);
+ current->thread.prev_sched = NULL;
+
+ fn = current->thread.request.u.thread.proc;
+ arg = current->thread.request.u.thread.arg;
+
+ /*
+ * The return value is 1 if the kernel thread execs a process,
+ * 0 if it just exits
+ */
+ n = run_kernel_thread(fn, arg, ¤t->thread.exec_buf);
+ if (n == 1) {
+ /* Handle any immediate reschedules or signals */
+ interrupt_end();
+ userspace(¤t->thread.regs.regs);
+ }
+ else do_exit(0);
+}
+
+/* Called magically, see new_thread_handler above */
+void fork_handler(void)
+{
+ force_flush_all();
- /* Start the process and wait for it to kill itself */
- new_pid = clone(outer_tramp, (void *) sp, clone_flags, &arg);
- if(new_pid < 0)
- return(new_pid);
+ schedule_tail(current->thread.prev_sched);
- CATCH_EINTR(err = waitpid(new_pid, &status, 0));
- if(err < 0)
- panic("Waiting for outer trampoline failed - errno = %d",
- errno);
+ /*
+ * XXX: if interrupt_end() calls schedule, this call to
+ * arch_switch_to isn't needed. We could want to apply this to
+ * improve performance. -bb
+ */
+ arch_switch_to(current);
- if(!WIFSIGNALED(status) || (WTERMSIG(status) != SIGKILL))
- panic("outer trampoline didn't exit with SIGKILL, "
- "status = %d", status);
+ current->thread.prev_sched = NULL;
- return(arg.pid);
+ /* Handle any immediate reschedules or signals */
+ interrupt_end();
+
+ userspace(¤t->thread.regs.regs);
}
-static int ptrace_child(void *arg)
+int copy_thread(unsigned long clone_flags, unsigned long sp,
+ unsigned long stack_top, struct task_struct * p,
+ struct pt_regs *regs)
{
- int ret;
- int pid = os_getpid(), ppid = getppid();
- int sc_result;
+ void (*handler)(void);
+ int ret = 0;
+
+ p->thread = (struct thread_struct) INIT_THREAD;
+
+ if (current->thread.forking) {
+ memcpy(&p->thread.regs.regs, ®s->regs,
+ sizeof(p->thread.regs.regs));
+ REGS_SET_SYSCALL_RETURN(p->thread.regs.regs.gp, 0);
+ if (sp != 0)
+ REGS_SP(p->thread.regs.regs.gp) = sp;
- if(ptrace(PTRACE_TRACEME, 0, 0, 0) < 0){
- perror("ptrace");
- os_kill_process(pid, 0);
+ handler = fork_handler;
+
+ arch_copy_thread(¤t->thread.arch, &p->thread.arch);
}
- os_stop_process(pid);
-
- /*This syscall will be intercepted by the parent. Don't call more than
- * once, please.*/
- sc_result = os_getpid();
-
- if (sc_result == pid)
- ret = 1; /*Nothing modified by the parent, we are running
- normally.*/
- else if (sc_result == ppid)
- ret = 0; /*Expected in check_ptrace and check_sysemu when they
- succeed in modifying the stack frame*/
- else
- ret = 2; /*Serious trouble! This could be caused by a bug in
- host 2.6 SKAS3/2.6 patch before release -V6, together
- with a bug in the UML code itself.*/
- _exit(ret);
-}
-
-static int start_ptraced_child(void **stack_out)
-{
- void *stack;
- unsigned long sp;
- int pid, n, status;
-
- stack = mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE | PROT_EXEC,
- MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- if(stack == MAP_FAILED)
- panic("check_ptrace : mmap failed, errno = %d", errno);
- sp = (unsigned long) stack + PAGE_SIZE - sizeof(void *);
- pid = clone(ptrace_child, (void *) sp, SIGCHLD, NULL);
- if(pid < 0)
- panic("check_ptrace : clone failed, errno = %d", errno);
- CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
- if(n < 0)
- panic("check_ptrace : wait failed, errno = %d", errno);
- if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGSTOP))
- panic("check_ptrace : expected SIGSTOP, got status = %d",
- status);
-
- *stack_out = stack;
- return(pid);
-}
-
-/* When testing for SYSEMU support, if it is one of the broken versions, we must
- * just avoid using sysemu, not panic, but only if SYSEMU features are broken.
- * So only for SYSEMU features we test mustpanic, while normal host features
- * must work anyway!*/
-static int stop_ptraced_child(int pid, void *stack, int exitcode, int mustpanic)
-{
- int status, n, ret = 0;
-
- if(ptrace(PTRACE_CONT, pid, 0, 0) < 0)
- panic("check_ptrace : ptrace failed, errno = %d", errno);
- CATCH_EINTR(n = waitpid(pid, &status, 0));
- if(!WIFEXITED(status) || (WEXITSTATUS(status) != exitcode)) {
- int exit_with = WEXITSTATUS(status);
- if (exit_with == 2)
- printk("check_ptrace : child exited with status 2. "
- "Serious trouble happening! Try updating your "
- "host skas patch!\nDisabling SYSEMU support.");
- printk("check_ptrace : child exited with exitcode %d, while "
- "expecting %d; status 0x%x", exit_with,
- exitcode, status);
- if (mustpanic)
- panic("\n");
- else
- printk("\n");
- ret = -1;
+ else {
+ get_safe_registers(p->thread.regs.regs.gp);
+ p->thread.request.u.thread = current->thread.request.u.thread;
+ handler = new_thread_handler;
+ }
+
+ new_thread(task_stack_page(p), &p->thread.switch_buf, handler);
+
+ if (current->thread.forking) {
+ clear_flushed_tls(p);
+
+ /*
+ * Set a new TLS for the child thread?
+ */
+ if (clone_flags & CLONE_SETTLS)
+ ret = arch_copy_tls(p);
}
- if(munmap(stack, PAGE_SIZE) < 0)
- panic("check_ptrace : munmap failed, errno = %d", errno);
return ret;
}
-static int force_sysemu_disabled = 0;
+void initial_thread_cb(void (*proc)(void *), void *arg)
+{
+ int save_kmalloc_ok = kmalloc_ok;
+
+ kmalloc_ok = 0;
+ initial_thread_cb_skas(proc, arg);
+ kmalloc_ok = save_kmalloc_ok;
+}
+
+void default_idle(void)
+{
+ unsigned long long nsecs;
+
+ while (1) {
+ /* endless idle loop with no priority at all */
+
+ /*
+ * although we are an idle CPU, we do not want to
+ * get into the scheduler unnecessarily.
+ */
+ if (need_resched())
+ schedule();
+
+ tick_nohz_stop_sched_tick(1);
+ nsecs = disable_timer();
+ idle_sleep(nsecs);
+ tick_nohz_restart_sched_tick();
+ }
+}
+
+void cpu_idle(void)
+{
+ cpu_tasks[current_thread_info()->cpu].pid = os_getpid();
+ default_idle();
+}
+
+int __cant_sleep(void) {
+ return in_atomic() || irqs_disabled() || in_interrupt();
+ /* Is in_interrupt() really needed? */
+}
+
+int user_context(unsigned long sp)
+{
+ unsigned long stack;
+
+ stack = sp & (PAGE_MASK << CONFIG_KERNEL_STACK_ORDER);
+ return stack != (unsigned long) current_thread_info();
+}
+
+extern exitcall_t __uml_exitcall_begin, __uml_exitcall_end;
+
+void do_uml_exitcalls(void)
+{
+ exitcall_t *call;
+
+ call = &__uml_exitcall_end;
+ while (--call >= &__uml_exitcall_begin)
+ (*call)();
+}
+
+char *uml_strdup(const char *string)
+{
+ return kstrdup(string, GFP_KERNEL);
+}
+
+int copy_to_user_proc(void __user *to, void *from, int size)
+{
+ return copy_to_user(to, from, size);
+}
+
+int copy_from_user_proc(void *to, void __user *from, int size)
+{
+ return copy_from_user(to, from, size);
+}
+
+int clear_user_proc(void __user *buf, int size)
+{
+ return clear_user(buf, size);
+}
+
+int strlen_user_proc(char __user *str)
+{
+ return strlen_user(str);
+}
-static int __init nosysemu_cmd_param(char *str, int* add)
+int smp_sigio_handler(void)
{
- force_sysemu_disabled = 1;
+#ifdef CONFIG_SMP
+ int cpu = current_thread_info()->cpu;
+ IPI_handler(cpu);
+ if (cpu != 0)
+ return 1;
+#endif
return 0;
}
-__uml_setup("nosysemu", nosysemu_cmd_param,
- "nosysemu\n"
- " Turns off syscall emulation patch for ptrace (SYSEMU) on.\n"
- " SYSEMU is a performance-patch introduced by Laurent Vivier. It changes\n"
- " behaviour of ptrace() and helps reducing host context switch rate.\n"
- " To make it working, you need a kernel patch for your host, too.\n"
- " See http://perso.wanadoo.fr/laurent.vivier/UML/ for further information.\n\n");
-
-static void __init check_sysemu(void)
-{
- void *stack;
- int pid, syscall, n, status, count=0;
-
- printk("Checking syscall emulation patch for ptrace...");
- sysemu_supported = 0;
- pid = start_ptraced_child(&stack);
-
- if(ptrace(PTRACE_SYSEMU, pid, 0, 0) < 0)
- goto fail;
-
- CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
- if (n < 0)
- panic("check_sysemu : wait failed, errno = %d", errno);
- if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP))
- panic("check_sysemu : expected SIGTRAP, "
- "got status = %d", status);
-
- n = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_RET_OFFSET,
- os_getpid());
- if(n < 0)
- panic("check_sysemu : failed to modify system "
- "call return, errno = %d", errno);
-
- if (stop_ptraced_child(pid, stack, 0, 0) < 0)
- goto fail_stopped;
-
- sysemu_supported = 1;
- printk("OK\n");
- set_using_sysemu(!force_sysemu_disabled);
-
- printk("Checking advanced syscall emulation patch for ptrace...");
- pid = start_ptraced_child(&stack);
- while(1){
- count++;
- if(ptrace(PTRACE_SYSEMU_SINGLESTEP, pid, 0, 0) < 0)
- goto fail;
- CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
- if(n < 0)
- panic("check_ptrace : wait failed, errno = %d", errno);
- if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP))
- panic("check_ptrace : expected (SIGTRAP|SYSCALL_TRAP), "
- "got status = %d", status);
-
- syscall = ptrace(PTRACE_PEEKUSR, pid, PT_SYSCALL_NR_OFFSET,
- 0);
- if(syscall == __NR_getpid){
- if (!count)
- panic("check_ptrace : SYSEMU_SINGLESTEP doesn't singlestep");
- n = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_RET_OFFSET,
- os_getpid());
- if(n < 0)
- panic("check_sysemu : failed to modify system "
- "call return, errno = %d", errno);
- break;
- }
- }
- if (stop_ptraced_child(pid, stack, 0, 0) < 0)
- goto fail_stopped;
-
- sysemu_supported = 2;
- printk("OK\n");
-
- if ( !force_sysemu_disabled )
- set_using_sysemu(sysemu_supported);
- return;
-
-fail:
- stop_ptraced_child(pid, stack, 1, 0);
-fail_stopped:
- printk("missing\n");
-}
-
-void __init check_ptrace(void)
-{
- void *stack;
- int pid, syscall, n, status;
-
- printk("Checking that ptrace can change system call numbers...");
- pid = start_ptraced_child(&stack);
-
- if (ptrace(PTRACE_OLDSETOPTIONS, pid, 0, (void *)PTRACE_O_TRACESYSGOOD) < 0)
- panic("check_ptrace: PTRACE_SETOPTIONS failed, errno = %d", errno);
-
- while(1){
- if(ptrace(PTRACE_SYSCALL, pid, 0, 0) < 0)
- panic("check_ptrace : ptrace failed, errno = %d",
- errno);
- CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
- if(n < 0)
- panic("check_ptrace : wait failed, errno = %d", errno);
- if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP + 0x80))
- panic("check_ptrace : expected SIGTRAP + 0x80, "
- "got status = %d", status);
-
- syscall = ptrace(PTRACE_PEEKUSR, pid, PT_SYSCALL_NR_OFFSET,
- 0);
- if(syscall == __NR_getpid){
- n = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_NR_OFFSET,
- __NR_getppid);
- if(n < 0)
- panic("check_ptrace : failed to modify system "
- "call, errno = %d", errno);
- break;
- }
- }
- stop_ptraced_child(pid, stack, 0, 1);
- printk("OK\n");
- check_sysemu();
+int cpu(void)
+{
+ return current_thread_info()->cpu;
}
-int run_kernel_thread(int (*fn)(void *), void *arg, void **jmp_ptr)
+static atomic_t using_sysemu = ATOMIC_INIT(0);
+int sysemu_supported;
+
+void set_using_sysemu(int value)
{
- sigjmp_buf buf;
- int n;
+ if (value > sysemu_supported)
+ return;
+ atomic_set(&using_sysemu, value);
+}
- *jmp_ptr = &buf;
- n = sigsetjmp(buf, 1);
- if(n != 0)
- return(n);
- (*fn)(arg);
- return(0);
+int get_using_sysemu(void)
+{
+ return atomic_read(&using_sysemu);
}
-void forward_pending_sigio(int target)
+static int sysemu_proc_show(struct seq_file *m, void *v)
{
- sigset_t sigs;
+ seq_printf(m, "%d\n", get_using_sysemu());
+ return 0;
+}
+
+static int sysemu_proc_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, sysemu_proc_show, NULL);
+}
+
+static ssize_t sysemu_proc_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *pos)
+{
+ char tmp[2];
- if(sigpending(&sigs))
- panic("forward_pending_sigio : sigpending failed");
- if(sigismember(&sigs, SIGIO))
- kill(target, SIGIO);
+ if (copy_from_user(tmp, buf, 1))
+ return -EFAULT;
+
+ if (tmp[0] >= '0' && tmp[0] <= '2')
+ set_using_sysemu(tmp[0] - '0');
+ /* We use the first char, but pretend to write everything */
+ return count;
}
-#ifdef UML_CONFIG_MODE_SKAS
-static inline int check_skas3_ptrace_support(void)
+static const struct file_operations sysemu_proc_fops = {
+ .owner = THIS_MODULE,
+ .open = sysemu_proc_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+ .write = sysemu_proc_write,
+};
+
+int __init make_proc_sysemu(void)
{
- struct ptrace_faultinfo fi;
- void *stack;
- int pid, n, ret = 1;
+ struct proc_dir_entry *ent;
+ if (!sysemu_supported)
+ return 0;
- printf("Checking for the skas3 patch in the host...");
- pid = start_ptraced_child(&stack);
+ ent = proc_create("sysemu", 0600, NULL, &sysemu_proc_fops);
- n = ptrace(PTRACE_FAULTINFO, pid, 0, &fi);
- if (n < 0) {
- if(errno == EIO)
- printf("not found\n");
- else {
- perror("not found");
- }
- ret = 0;
- } else {
- printf("found\n");
+ if (ent == NULL)
+ {
+ printk(KERN_WARNING "Failed to register /proc/sysemu\n");
+ return 0;
}
- init_registers(pid);
- stop_ptraced_child(pid, stack, 1, 1);
+ return 0;
+}
+
+late_initcall(make_proc_sysemu);
- return(ret);
+int singlestepping(void * t)
+{
+ struct task_struct *task = t ? t : current;
+
+ if (!(task->ptrace & PT_DTRACE))
+ return 0;
+
+ if (task->thread.singlestep_syscall)
+ return 1;
+
+ return 2;
}
-int can_do_skas(void)
+/*
+ * Only x86 and x86_64 have an arch_align_stack().
+ * All other arches have "#define arch_align_stack(x) (x)"
+ * in their asm/system.h
+ * As this is included in UML from asm-um/system-generic.h,
+ * we can use it to behave as the subarch does.
+ */
+#ifndef arch_align_stack
+unsigned long arch_align_stack(unsigned long sp)
{
- int ret = 1;
+ if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
+ sp -= get_random_int() % 8192;
+ return sp & ~0xf;
+}
+#endif
- printf("Checking for /proc/mm...");
- if (os_access("/proc/mm", OS_ACC_W_OK) < 0) {
- printf("not found\n");
- ret = 0;
- goto out;
- } else {
- printf("found\n");
+unsigned long get_wchan(struct task_struct *p)
+{
+ unsigned long stack_page, sp, ip;
+ bool seen_sched = 0;
+
+ if ((p == NULL) || (p == current) || (p->state == TASK_RUNNING))
+ return 0;
+
+ stack_page = (unsigned long) task_stack_page(p);
+ /* Bail if the process has no kernel stack for some reason */
+ if (stack_page == 0)
+ return 0;
+
+ sp = p->thread.switch_buf->JB_SP;
+ /*
+ * Bail if the stack pointer is below the bottom of the kernel
+ * stack for some reason
+ */
+ if (sp < stack_page)
+ return 0;
+
+ while (sp < stack_page + THREAD_SIZE) {
+ ip = *((unsigned long *) sp);
+ if (in_sched_functions(ip))
+ /* Ignore everything until we're above the scheduler */
+ seen_sched = 1;
+ else if (kernel_text_address(ip) && seen_sched)
+ return ip;
+
+ sp += sizeof(unsigned long);
}
- ret = check_skas3_ptrace_support();
-out:
- return ret;
+ return 0;
}
-#else
-int can_do_skas(void)
+
+int elf_core_copy_fpregs(struct task_struct *t, elf_fpregset_t *fpu)
{
- return(0);
+ int cpu = current_thread_info()->cpu;
+
+ return save_fp_registers(userspace_pid[cpu], (unsigned long *) fpu);
}
-#endif
+
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