void fixup_BUG(struct pt_regs *regs) { BUG_regs = *regs; #ifdef CONFIG_DEBUG_BUGVERBOSE /* * Fixup the BUG arguments through exception handlers. */ { const struct exception_table_entry *fixup; /* * ERP points at the "break 14" + 2, compensate for the 2 * bytes. */ fixup = search_exception_tables(instruction_pointer(regs) - 2); if (fixup) { /* Adjust the instruction pointer in the stackframe. */ instruction_pointer(regs) = fixup->fixup; arch_fixup(regs); } } #else /* Dont try to lookup the filename + line, just dump regs. */ do_BUG("unknown", 0); #endif }
/* * We give a *copy* of the faultinfo in the regs to segv. * This must be done, since nesting SEGVs could overwrite * the info in the regs. A pointer to the info then would * give us bad data! */ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, void *sc) { struct siginfo si; void *catcher; int err; int is_write = FAULT_WRITE(fi); unsigned long address = FAULT_ADDRESS(fi); if(!is_user && (address >= start_vm) && (address < end_vm)){ flush_tlb_kernel_vm(); return(0); } else if(current->mm == NULL) panic("Segfault with no mm"); if (SEGV_IS_FIXABLE(&fi) || SEGV_MAYBE_FIXABLE(&fi)) err = handle_page_fault(address, ip, is_write, is_user, &si.si_code); else { err = -EFAULT; /* A thread accessed NULL, we get a fault, but CR2 is invalid. * This code is used in __do_copy_from_user() of TT mode. */ address = 0; } catcher = current->thread.fault_catcher; if(!err) return(0); else if(catcher != NULL){ current->thread.fault_addr = (void *) address; do_longjmp(catcher, 1); } else if(current->thread.fault_addr != NULL) panic("fault_addr set but no fault catcher"); else if(!is_user && arch_fixup(ip, sc)) return(0); if(!is_user) panic("Kernel mode fault at addr 0x%lx, ip 0x%lx", address, ip); if (err == -EACCES) { si.si_signo = SIGBUS; si.si_errno = 0; si.si_code = BUS_ADRERR; si.si_addr = (void __user *)address; current->thread.arch.faultinfo = fi; force_sig_info(SIGBUS, &si, current); } else if (err == -ENOMEM) { printk("VM: killing process %s\n", current->comm); do_exit(SIGKILL); } else { BUG_ON(err != -EFAULT); si.si_signo = SIGSEGV; si.si_addr = (void __user *) address; current->thread.arch.faultinfo = fi; force_sig_info(SIGSEGV, &si, current); } return(0); }
/* Find fixup code. */ int find_fixup_code(struct pt_regs *regs) { const struct exception_table_entry *fixup; if ((fixup = search_exception_tables(instruction_pointer(regs))) != 0) { /* Adjust the instruction pointer in the stackframe. */ instruction_pointer(regs) = fixup->fixup; arch_fixup(regs); return 1; } return 0; }
/* Find fixup code. */ int find_fixup_code(struct pt_regs *regs) { const struct exception_table_entry *fixup; /* in case of delay slot fault (v32) */ unsigned long ip = (instruction_pointer(regs) & ~0x1); fixup = search_exception_tables(ip); if (fixup != 0) { /* Adjust the instruction pointer in the stackframe. */ instruction_pointer(regs) = fixup->fixup; arch_fixup(regs); return 1; } return 0; }
/* * We give a *copy* of the faultinfo in the regs to segv. * This must be done, since nesting SEGVs could overwrite * the info in the regs. A pointer to the info then would * give us bad data! */ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, struct uml_pt_regs *regs) { struct siginfo si; jmp_buf *catcher; int err; int is_write = FAULT_WRITE(fi); unsigned long address = FAULT_ADDRESS(fi); if (!is_user && (address >= start_vm) && (address < end_vm)) { flush_tlb_kernel_vm(); return 0; } else if (current->mm == NULL) { show_regs(container_of(regs, struct pt_regs, regs)); panic("Segfault with no mm"); } if (SEGV_IS_FIXABLE(&fi) || SEGV_MAYBE_FIXABLE(&fi)) err = handle_page_fault(address, ip, is_write, is_user, &si.si_code); else { err = -EFAULT; /* * A thread accessed NULL, we get a fault, but CR2 is invalid. * This code is used in __do_copy_from_user() of TT mode. * XXX tt mode is gone, so maybe this isn't needed any more */ address = 0; } catcher = current->thread.fault_catcher; if (!err) return 0; else if (catcher != NULL) { current->thread.fault_addr = (void *) address; UML_LONGJMP(catcher, 1); } else if (current->thread.fault_addr != NULL) panic("fault_addr set but no fault catcher"); else if (!is_user && arch_fixup(ip, regs)) return 0; if (!is_user) { show_regs(container_of(regs, struct pt_regs, regs)); panic("Kernel mode fault at addr 0x%lx, ip 0x%lx", address, ip); } if (err == -EACCES) { si.si_signo = SIGBUS; si.si_errno = 0; si.si_code = BUS_ADRERR; si.si_addr = (void __user *)address; current->thread.arch.faultinfo = fi; force_sig_info(SIGBUS, &si, current); } else if (err == -ENOMEM) { printk(KERN_INFO "VM: killing process %s\n", current->comm); do_exit(SIGKILL); } else { BUG_ON(err != -EFAULT); si.si_signo = SIGSEGV; si.si_addr = (void __user *) address; current->thread.arch.faultinfo = fi; force_sig_info(SIGSEGV, &si, current); } return 0; }