2 * Common signal handling code for both 32 and 64 bits
4 * Copyright (c) 2007 Benjamin Herrenschmidt, IBM Coproration
5 * Extracted from signal_32.c and signal_64.c
7 * This file is subject to the terms and conditions of the GNU General
8 * Public License. See the file README.legal in the main directory of
9 * this archive for more details.
12 #include <linux/tracehook.h>
13 #include <linux/signal.h>
14 #include <linux/uprobes.h>
15 #include <linux/key.h>
16 #include <asm/hw_breakpoint.h>
17 #include <asm/uaccess.h>
18 #include <asm/unistd.h>
19 #include <asm/debug.h>
23 /* Log an error when sending an unhandled signal to a process. Controlled
24 * through debug.exception-trace sysctl.
27 int show_unhandled_signals = 0;
30 * Allocate space for the signal frame
32 void __user * get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
33 size_t frame_size, int is_32)
35 unsigned long oldsp, newsp;
37 /* Default to using normal stack */
38 oldsp = get_clean_sp(regs, is_32);
40 /* Check for alt stack */
41 if ((ka->sa.sa_flags & SA_ONSTACK) &&
42 current->sas_ss_size && !on_sig_stack(oldsp))
43 oldsp = (current->sas_ss_sp + current->sas_ss_size);
45 /* Get aligned frame */
46 newsp = (oldsp - frame_size) & ~0xFUL;
49 if (!access_ok(VERIFY_WRITE, (void __user *)newsp, oldsp - newsp))
52 return (void __user *)newsp;
55 static void check_syscall_restart(struct pt_regs *regs, struct k_sigaction *ka,
58 unsigned long ret = regs->gpr[3];
62 if (TRAP(regs) != 0x0C00)
65 /* error signalled ? */
66 if (!(regs->ccr & 0x10000000))
70 case ERESTART_RESTARTBLOCK:
72 /* ERESTARTNOHAND means that the syscall should only be
73 * restarted if there was no handler for the signal, and since
74 * we only get here if there is a handler, we dont restart.
76 restart = !has_handler;
79 /* ERESTARTSYS means to restart the syscall if there is no
80 * handler or the handler was registered with SA_RESTART
82 restart = !has_handler || (ka->sa.sa_flags & SA_RESTART) != 0;
85 /* ERESTARTNOINTR means that the syscall should be
86 * called again after the signal handler returns.
93 if (ret == ERESTART_RESTARTBLOCK)
94 regs->gpr[0] = __NR_restart_syscall;
96 regs->gpr[3] = regs->orig_gpr3;
100 regs->result = -EINTR;
101 regs->gpr[3] = EINTR;
102 regs->ccr |= 0x10000000;
106 static int do_signal(struct pt_regs *regs)
108 sigset_t *oldset = sigmask_to_save();
111 struct k_sigaction ka;
113 int is32 = is_32bit_task();
115 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
117 /* Is there any syscall restart business here ? */
118 check_syscall_restart(regs, &ka, signr > 0);
121 /* No signal to deliver -- put the saved sigmask back */
122 restore_saved_sigmask();
124 return 0; /* no signals delivered */
127 #ifndef CONFIG_PPC_ADV_DEBUG_REGS
129 * Reenable the DABR before delivering the signal to
130 * user space. The DABR will have been cleared if it
131 * triggered inside the kernel.
133 if (current->thread.hw_brk.address &&
134 current->thread.hw_brk.type)
135 set_breakpoint(¤t->thread.hw_brk);
137 /* Re-enable the breakpoints for the signal stack */
138 thread_change_pc(current, regs);
141 if (ka.sa.sa_flags & SA_SIGINFO)
142 ret = handle_rt_signal32(signr, &ka, &info, oldset,
145 ret = handle_signal32(signr, &ka, &info, oldset,
148 ret = handle_rt_signal64(signr, &ka, &info, oldset, regs);
153 signal_delivered(signr, &info, &ka, regs,
154 test_thread_flag(TIF_SINGLESTEP));
160 void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags)
162 if (thread_info_flags & _TIF_UPROBE)
163 uprobe_notify_resume(regs);
165 if (thread_info_flags & _TIF_SIGPENDING)
168 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
169 clear_thread_flag(TIF_NOTIFY_RESUME);
170 tracehook_notify_resume(regs);