diff options
Diffstat (limited to 'arch/tile/kernel/signal.c')
-rw-r--r-- | arch/tile/kernel/signal.c | 411 |
1 files changed, 0 insertions, 411 deletions
diff --git a/arch/tile/kernel/signal.c b/arch/tile/kernel/signal.c deleted file mode 100644 index f2bf557bb005..000000000000 --- a/arch/tile/kernel/signal.c +++ /dev/null @@ -1,411 +0,0 @@ -/* - * Copyright (C) 1991, 1992 Linus Torvalds - * Copyright 2010 Tilera Corporation. All Rights Reserved. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation, version 2. - * - * This program is distributed in the hope that it will be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or - * NON INFRINGEMENT. See the GNU General Public License for - * more details. - */ - -#include <linux/sched.h> -#include <linux/sched/debug.h> -#include <linux/sched/task_stack.h> -#include <linux/mm.h> -#include <linux/smp.h> -#include <linux/kernel.h> -#include <linux/signal.h> -#include <linux/errno.h> -#include <linux/wait.h> -#include <linux/unistd.h> -#include <linux/stddef.h> -#include <linux/personality.h> -#include <linux/suspend.h> -#include <linux/ptrace.h> -#include <linux/elf.h> -#include <linux/compat.h> -#include <linux/syscalls.h> -#include <linux/uaccess.h> -#include <asm/processor.h> -#include <asm/ucontext.h> -#include <asm/sigframe.h> -#include <asm/syscalls.h> -#include <asm/vdso.h> -#include <arch/interrupts.h> - -#define DEBUG_SIG 0 - -/* - * Do a signal return; undo the signal stack. - */ - -int restore_sigcontext(struct pt_regs *regs, - struct sigcontext __user *sc) -{ - int err; - - /* Always make any pending restarted system calls return -EINTR */ - current->restart_block.fn = do_no_restart_syscall; - - /* - * Enforce that sigcontext is like pt_regs, and doesn't mess - * up our stack alignment rules. - */ - BUILD_BUG_ON(sizeof(struct sigcontext) != sizeof(struct pt_regs)); - BUILD_BUG_ON(sizeof(struct sigcontext) % 8 != 0); - err = __copy_from_user(regs, sc, sizeof(*regs)); - - /* Ensure that the PL is always set to USER_PL. */ - regs->ex1 = PL_ICS_EX1(USER_PL, EX1_ICS(regs->ex1)); - - regs->faultnum = INT_SWINT_1_SIGRETURN; - - return err; -} - -void signal_fault(const char *type, struct pt_regs *regs, - void __user *frame, int sig) -{ - trace_unhandled_signal(type, regs, (unsigned long)frame, SIGSEGV); - force_sigsegv(sig, current); -} - -/* The assembly shim for this function arranges to ignore the return value. */ -SYSCALL_DEFINE0(rt_sigreturn) -{ - struct pt_regs *regs = current_pt_regs(); - struct rt_sigframe __user *frame = - (struct rt_sigframe __user *)(regs->sp); - sigset_t set; - - if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) - goto badframe; - if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) - goto badframe; - - set_current_blocked(&set); - - if (restore_sigcontext(regs, &frame->uc.uc_mcontext)) - goto badframe; - - if (restore_altstack(&frame->uc.uc_stack)) - goto badframe; - - return 0; - -badframe: - signal_fault("bad sigreturn frame", regs, frame, 0); - return 0; -} - -/* - * Set up a signal frame. - */ - -int setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs) -{ - return __copy_to_user(sc, regs, sizeof(*regs)); -} - -/* - * Determine which stack to use.. - */ -static inline void __user *get_sigframe(struct k_sigaction *ka, - struct pt_regs *regs, - size_t frame_size) -{ - unsigned long sp; - - /* Default to using normal stack */ - sp = regs->sp; - - /* - * If we are on the alternate signal stack and would overflow - * it, don't. Return an always-bogus address instead so we - * will die with SIGSEGV. - */ - if (on_sig_stack(sp) && !likely(on_sig_stack(sp - frame_size))) - return (void __user __force *)-1UL; - - /* This is the X/Open sanctioned signal stack switching. */ - if (ka->sa.sa_flags & SA_ONSTACK) { - if (sas_ss_flags(sp) == 0) - sp = current->sas_ss_sp + current->sas_ss_size; - } - - sp -= frame_size; - /* - * Align the stack pointer according to the TILE ABI, - * i.e. so that on function entry (sp & 15) == 0. - */ - sp &= -16UL; - return (void __user *) sp; -} - -static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, - struct pt_regs *regs) -{ - unsigned long restorer; - struct rt_sigframe __user *frame; - int err = 0, sig = ksig->sig; - - frame = get_sigframe(&ksig->ka, regs, sizeof(*frame)); - - if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) - goto err; - - /* Always write at least the signal number for the stack backtracer. */ - if (ksig->ka.sa.sa_flags & SA_SIGINFO) { - /* At sigreturn time, restore the callee-save registers too. */ - err |= copy_siginfo_to_user(&frame->info, &ksig->info); - regs->flags |= PT_FLAGS_RESTORE_REGS; - } else { - err |= __put_user(ksig->info.si_signo, &frame->info.si_signo); - } - - /* Create the ucontext. */ - err |= __clear_user(&frame->save_area, sizeof(frame->save_area)); - err |= __put_user(0, &frame->uc.uc_flags); - err |= __put_user(NULL, &frame->uc.uc_link); - err |= __save_altstack(&frame->uc.uc_stack, regs->sp); - err |= setup_sigcontext(&frame->uc.uc_mcontext, regs); - err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); - if (err) - goto err; - - restorer = VDSO_SYM(&__vdso_rt_sigreturn); - if (ksig->ka.sa.sa_flags & SA_RESTORER) - restorer = (unsigned long) ksig->ka.sa.sa_restorer; - - /* - * Set up registers for signal handler. - * Registers that we don't modify keep the value they had from - * user-space at the time we took the signal. - * We always pass siginfo and mcontext, regardless of SA_SIGINFO, - * since some things rely on this (e.g. glibc's debug/segfault.c). - */ - regs->pc = (unsigned long) ksig->ka.sa.sa_handler; - regs->ex1 = PL_ICS_EX1(USER_PL, 1); /* set crit sec in handler */ - regs->sp = (unsigned long) frame; - regs->lr = restorer; - regs->regs[0] = (unsigned long) sig; - regs->regs[1] = (unsigned long) &frame->info; - regs->regs[2] = (unsigned long) &frame->uc; - regs->flags |= PT_FLAGS_CALLER_SAVES; - return 0; - -err: - trace_unhandled_signal("bad sigreturn frame", regs, - (unsigned long)frame, SIGSEGV); - return -EFAULT; -} - -/* - * OK, we're invoking a handler - */ - -static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) -{ - sigset_t *oldset = sigmask_to_save(); - int ret; - - /* Are we from a system call? */ - if (regs->faultnum == INT_SWINT_1) { - /* If so, check system call restarting.. */ - switch (regs->regs[0]) { - case -ERESTART_RESTARTBLOCK: - case -ERESTARTNOHAND: - regs->regs[0] = -EINTR; - break; - - case -ERESTARTSYS: - if (!(ksig->ka.sa.sa_flags & SA_RESTART)) { - regs->regs[0] = -EINTR; - break; - } - /* fallthrough */ - case -ERESTARTNOINTR: - /* Reload caller-saves to restore r0..r5 and r10. */ - regs->flags |= PT_FLAGS_CALLER_SAVES; - regs->regs[0] = regs->orig_r0; - regs->pc -= 8; - } - } - - /* Set up the stack frame */ -#ifdef CONFIG_COMPAT - if (is_compat_task()) - ret = compat_setup_rt_frame(ksig, oldset, regs); - else -#endif - ret = setup_rt_frame(ksig, oldset, regs); - - signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP)); -} - -/* - * Note that 'init' is a special process: it doesn't get signals it doesn't - * want to handle. Thus you cannot kill init even with a SIGKILL even by - * mistake. - */ -void do_signal(struct pt_regs *regs) -{ - struct ksignal ksig; - - /* - * i386 will check if we're coming from kernel mode and bail out - * here. In my experience this just turns weird crashes into - * weird spin-hangs. But if we find a case where this seems - * helpful, we can reinstate the check on "!user_mode(regs)". - */ - - if (get_signal(&ksig)) { - /* Whee! Actually deliver the signal. */ - handle_signal(&ksig, regs); - goto done; - } - - /* Did we come from a system call? */ - if (regs->faultnum == INT_SWINT_1) { - /* Restart the system call - no handlers present */ - switch (regs->regs[0]) { - case -ERESTARTNOHAND: - case -ERESTARTSYS: - case -ERESTARTNOINTR: - regs->flags |= PT_FLAGS_CALLER_SAVES; - regs->regs[0] = regs->orig_r0; - regs->pc -= 8; - break; - - case -ERESTART_RESTARTBLOCK: - regs->flags |= PT_FLAGS_CALLER_SAVES; - regs->regs[TREG_SYSCALL_NR] = __NR_restart_syscall; - regs->pc -= 8; - break; - } - } - - /* If there's no signal to deliver, just put the saved sigmask back. */ - restore_saved_sigmask(); - -done: - /* Avoid double syscall restart if there are nested signals. */ - regs->faultnum = INT_SWINT_1_SIGRETURN; -} - -int show_unhandled_signals = 1; - -static int __init crashinfo(char *str) -{ - const char *word; - - if (*str == '\0') - show_unhandled_signals = 2; - else if (*str != '=' || kstrtoint(++str, 0, &show_unhandled_signals) != 0) - return 0; - - switch (show_unhandled_signals) { - case 0: - word = "No"; - break; - case 1: - word = "One-line"; - break; - default: - word = "Detailed"; - break; - } - pr_info("%s crash reports will be generated on the console\n", word); - return 1; -} -__setup("crashinfo", crashinfo); - -static void dump_mem(void __user *address) -{ - void __user *addr; - enum { region_size = 256, bytes_per_line = 16 }; - int i, j, k; - int found_readable_mem = 0; - - if (!access_ok(VERIFY_READ, address, 1)) { - pr_err("Not dumping at address 0x%lx (kernel address)\n", - (unsigned long)address); - return; - } - - addr = (void __user *) - (((unsigned long)address & -bytes_per_line) - region_size/2); - if (addr > address) - addr = NULL; - for (i = 0; i < region_size; - addr += bytes_per_line, i += bytes_per_line) { - unsigned char buf[bytes_per_line]; - char line[100]; - if (copy_from_user(buf, addr, bytes_per_line)) - continue; - if (!found_readable_mem) { - pr_err("Dumping memory around address 0x%lx:\n", - (unsigned long)address); - found_readable_mem = 1; - } - j = sprintf(line, REGFMT ":", (unsigned long)addr); - for (k = 0; k < bytes_per_line; ++k) - j += sprintf(&line[j], " %02x", buf[k]); - pr_err("%s\n", line); - } - if (!found_readable_mem) - pr_err("No readable memory around address 0x%lx\n", - (unsigned long)address); -} - -void trace_unhandled_signal(const char *type, struct pt_regs *regs, - unsigned long address, int sig) -{ - struct task_struct *tsk = current; - - if (show_unhandled_signals == 0) - return; - - /* If the signal is handled, don't show it here. */ - if (!is_global_init(tsk)) { - void __user *handler = - tsk->sighand->action[sig-1].sa.sa_handler; - if (handler != SIG_IGN && handler != SIG_DFL) - return; - } - - /* Rate-limit the one-line output, not the detailed output. */ - if (show_unhandled_signals <= 1 && !printk_ratelimit()) - return; - - printk("%s%s[%d]: %s at %lx pc "REGFMT" signal %d", - task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG, - tsk->comm, task_pid_nr(tsk), type, address, regs->pc, sig); - - print_vma_addr(KERN_CONT " in ", regs->pc); - - printk(KERN_CONT "\n"); - - if (show_unhandled_signals > 1) { - switch (sig) { - case SIGILL: - case SIGFPE: - case SIGSEGV: - case SIGBUS: - pr_err("User crash: signal %d, trap %ld, address 0x%lx\n", - sig, regs->faultnum, address); - show_regs(regs); - dump_mem((void __user *)address); - break; - default: - pr_err("User crash: signal %d, trap %ld\n", - sig, regs->faultnum); - break; - } - } -} |