}
asmlinkage long
-sys_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, long arg2, long arg3, long arg4,
- long arg5, long arg6, long arg7, long stack)
+sys_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, long arg2,
+ long arg3, long arg4, long arg5, long arg6, long arg7,
+ struct pt_regs regs)
{
- struct pt_regs *pt = (struct pt_regs *) &stack;
-
- return do_sigaltstack(uss, uoss, pt->r12);
+ return do_sigaltstack(uss, uoss, regs.r12);
}
static long
* could be corrupted.
*/
retval = (long) &ia64_leave_kernel;
- if (test_thread_flag(TIF_SYSCALL_TRACE))
+ if (test_thread_flag(TIF_SYSCALL_TRACE)
+ || test_thread_flag(TIF_SYSCALL_AUDIT))
/*
* strace expects to be notified after sigreturn returns even though the
* context to which we return may not be in the middle of a syscall.
if (on_sig_stack((unsigned long) sc))
flags |= IA64_SC_FLAG_ONSTACK;
- if ((ifs & (1UL << 63)) == 0) {
- /* if cr_ifs isn't valid, we got here through a syscall */
+ if ((ifs & (1UL << 63)) == 0)
+ /* if cr_ifs doesn't have the valid bit set, we got here through a syscall */
flags |= IA64_SC_FLAG_IN_SYSCALL;
- cfm = scr->ar_pfs & ((1UL << 38) - 1);
- } else
- cfm = ifs & ((1UL << 38) - 1);
+ cfm = ifs & ((1UL << 38) - 1);
ia64_flush_fph(current);
if ((current->thread.flags & IA64_THREAD_FPH_VALID)) {
flags |= IA64_SC_FLAG_FPH_VALID;
}
return 0;
}
+
+/* Set a delayed signal that was detected in MCA/INIT/NMI/PMI context where it
+ * could not be delivered. It is important that the target process is not
+ * allowed to do any more work in user space. Possible cases for the target
+ * process:
+ *
+ * - It is sleeping and will wake up soon. Store the data in the current task,
+ * the signal will be sent when the current task returns from the next
+ * interrupt.
+ *
+ * - It is running in user context. Store the data in the current task, the
+ * signal will be sent when the current task returns from the next interrupt.
+ *
+ * - It is running in kernel context on this or another cpu and will return to
+ * user context. Store the data in the target task, the signal will be sent
+ * to itself when the target task returns to user space.
+ *
+ * - It is running in kernel context on this cpu and will sleep before
+ * returning to user context. Because this is also the current task, the
+ * signal will not get delivered and the task could sleep indefinitely.
+ * Store the data in the idle task for this cpu, the signal will be sent
+ * after the idle task processes its next interrupt.
+ *
+ * To cover all cases, store the data in the target task, the current task and
+ * the idle task on this cpu. Whatever happens, the signal will be delivered
+ * to the target task before it can do any useful user space work. Multiple
+ * deliveries have no unwanted side effects.
+ *
+ * Note: This code is executed in MCA/INIT/NMI/PMI context, with interrupts
+ * disabled. It must not take any locks nor use kernel structures or services
+ * that require locks.
+ */
+
+/* To ensure that we get the right pid, check its start time. To avoid extra
+ * include files in thread_info.h, convert the task start_time to unsigned long,
+ * giving us a cycle time of > 580 years.
+ */
+static inline unsigned long
+start_time_ul(const struct task_struct *t)
+{
+ return t->start_time.tv_sec * NSEC_PER_SEC + t->start_time.tv_nsec;
+}
+
+void
+set_sigdelayed(pid_t pid, int signo, int code, void __user *addr)
+{
+ struct task_struct *t;
+ unsigned long start_time = 0;
+ int i;
+
+ for (i = 1; i <= 3; ++i) {
+ switch (i) {
+ case 1:
+ t = find_task_by_pid(pid);
+ if (t)
+ start_time = start_time_ul(t);
+ break;
+ case 2:
+ t = current;
+ break;
+ default:
+ t = idle_task(smp_processor_id());
+ break;
+ }
+
+ if (!t)
+ return;
+ t->thread_info->sigdelayed.signo = signo;
+ t->thread_info->sigdelayed.code = code;
+ t->thread_info->sigdelayed.addr = addr;
+ t->thread_info->sigdelayed.start_time = start_time;
+ t->thread_info->sigdelayed.pid = pid;
+ wmb();
+ set_tsk_thread_flag(t, TIF_SIGDELAYED);
+ }
+}
+
+/* Called from entry.S when it detects TIF_SIGDELAYED, a delayed signal that
+ * was detected in MCA/INIT/NMI/PMI context where it could not be delivered.
+ */
+
+void
+do_sigdelayed(void)
+{
+ struct siginfo siginfo;
+ pid_t pid;
+ struct task_struct *t;
+
+ clear_thread_flag(TIF_SIGDELAYED);
+ memset(&siginfo, 0, sizeof(siginfo));
+ siginfo.si_signo = current_thread_info()->sigdelayed.signo;
+ siginfo.si_code = current_thread_info()->sigdelayed.code;
+ siginfo.si_addr = current_thread_info()->sigdelayed.addr;
+ pid = current_thread_info()->sigdelayed.pid;
+ t = find_task_by_pid(pid);
+ if (!t)
+ return;
+ if (current_thread_info()->sigdelayed.start_time != start_time_ul(t))
+ return;
+ force_sig_info(siginfo.si_signo, &siginfo, t);
+}
git://git.onelab.eu / linux-2.6.git / blobdiff