/* * arch/ia64/kernel/crash.c * * Architecture specific (ia64) functions for kexec based crash dumps. * * Created by: Khalid Aziz * Copyright (C) 2005 Hewlett-Packard Development Company, L.P. * Copyright (C) 2005 Intel Corp Zou Nan hai * */ #include #include #include #include #include #include #include #include #include #include int kdump_status[NR_CPUS]; static atomic_t kdump_cpu_frozen; atomic_t kdump_in_progress; static int kdump_freeze_monarch; static int kdump_on_init = 1; static int kdump_on_fatal_mca = 1; static inline Elf64_Word *append_elf_note(Elf64_Word *buf, char *name, unsigned type, void *data, size_t data_len) { struct elf_note *note = (struct elf_note *)buf; note->n_namesz = strlen(name) + 1; note->n_descsz = data_len; note->n_type = type; buf += (sizeof(*note) + 3)/4; memcpy(buf, name, note->n_namesz); buf += (note->n_namesz + 3)/4; memcpy(buf, data, data_len); buf += (data_len + 3)/4; return buf; } static void final_note(void *buf) { memset(buf, 0, sizeof(struct elf_note)); } extern void ia64_dump_cpu_regs(void *); static DEFINE_PER_CPU(struct elf_prstatus, elf_prstatus); void crash_save_this_cpu(void) { void *buf; unsigned long cfm, sof, sol; int cpu = smp_processor_id(); struct elf_prstatus *prstatus = &per_cpu(elf_prstatus, cpu); elf_greg_t *dst = (elf_greg_t *)&(prstatus->pr_reg); memset(prstatus, 0, sizeof(*prstatus)); prstatus->pr_pid = current->pid; ia64_dump_cpu_regs(dst); cfm = dst[43]; sol = (cfm >> 7) & 0x7f; sof = cfm & 0x7f; dst[46] = (unsigned long)ia64_rse_skip_regs((unsigned long *)dst[46], sof - sol); buf = (u64 *) per_cpu_ptr(crash_notes, cpu); if (!buf) return; buf = append_elf_note(buf, KEXEC_CORE_NOTE_NAME, NT_PRSTATUS, prstatus, sizeof(*prstatus)); final_note(buf); } #ifdef CONFIG_SMP static int kdump_wait_cpu_freeze(void) { int cpu_num = num_online_cpus() - 1; int timeout = 1000; while(timeout-- > 0) { if (atomic_read(&kdump_cpu_frozen) == cpu_num) return 0; udelay(1000); } return 1; } #endif void machine_crash_shutdown(struct pt_regs *pt) { /* This function is only called after the system * has paniced or is otherwise in a critical state. * The minimum amount of code to allow a kexec'd kernel * to run successfully needs to happen here. * * In practice this means shooting down the other cpus in * an SMP system. */ kexec_disable_iosapic(); #ifdef CONFIG_SMP /* * If kdump_on_init is set and an INIT is asserted here, kdump will * be started again via INIT monarch. */ local_irq_disable(); ia64_set_psr_mc(); /* mask MCA/INIT */ if (atomic_inc_return(&kdump_in_progress) != 1) unw_init_running(kdump_cpu_freeze, NULL); /* * Now this cpu is ready for kdump. * Stop all others by IPI or INIT. They could receive INIT from * outside and might be INIT monarch, but only thing they have to * do is falling into kdump_cpu_freeze(). * * If an INIT is asserted here: * - All receivers might be slaves, since some of cpus could already * be frozen and INIT might be masked on monarch. In this case, * all slaves will be frozen soon since kdump_in_progress will let * them into DIE_INIT_SLAVE_LEAVE. * - One might be a monarch, but INIT rendezvous will fail since * at least this cpu already have INIT masked so it never join * to the rendezvous. In this case, all slaves and monarch will * be frozen soon with no wait since the INIT rendezvous is skipped * by kdump_in_progress. */ kdump_smp_send_stop(); /* not all cpu response to IPI, send INIT to freeze them */ if (kdump_wait_cpu_freeze()) { kdump_smp_send_init(); /* wait again, don't go ahead if possible */ kdump_wait_cpu_freeze(); } #endif } static void machine_kdump_on_init(void) { crash_save_vmcoreinfo(); local_irq_disable(); kexec_disable_iosapic(); machine_kexec(ia64_kimage); } void kdump_cpu_freeze(struct unw_frame_info *info, void *arg) { int cpuid; local_irq_disable(); cpuid = smp_processor_id(); crash_save_this_cpu(); current->thread.ksp = (__u64)info->sw - 16; ia64_set_psr_mc(); /* mask MCA/INIT and stop reentrance */ atomic_inc(&kdump_cpu_frozen); kdump_status[cpuid] = 1; mb(); for (;;) cpu_relax(); } static int kdump_init_notifier(struct notifier_block *self, unsigned long val, void *data) { struct ia64_mca_notify_die *nd; struct die_args *args = data; if (atomic_read(&kdump_in_progress)) { switch (val) { case DIE_INIT_MONARCH_LEAVE: if (!kdump_freeze_monarch) break; /* fall through */ case DIE_INIT_SLAVE_LEAVE: case DIE_INIT_MONARCH_ENTER: case DIE_MCA_RENDZVOUS_LEAVE: unw_init_running(kdump_cpu_freeze, NULL); break; } } if (!kdump_on_init && !kdump_on_fatal_mca) return NOTIFY_DONE; if (!ia64_kimage) { if (val == DIE_INIT_MONARCH_LEAVE) ia64_mca_printk(KERN_NOTICE "%s: kdump not configured\n", __func__); return NOTIFY_DONE; } if (val != DIE_INIT_MONARCH_LEAVE && val != DIE_INIT_MONARCH_PROCESS && val != DIE_MCA_MONARCH_LEAVE) return NOTIFY_DONE; nd = (struct ia64_mca_notify_die *)args->err; switch (val) { case DIE_INIT_MONARCH_PROCESS: /* Reason code 1 means machine check rendezvous*/ if (kdump_on_init && (nd->sos->rv_rc != 1)) { if (atomic_inc_return(&kdump_in_progress) != 1) kdump_freeze_monarch = 1; } break; case DIE_INIT_MONARCH_LEAVE: /* Reason code 1 means machine check rendezvous*/ if (kdump_on_init && (nd->sos->rv_rc != 1)) machine_kdump_on_init(); break; case DIE_MCA_MONARCH_LEAVE: /* *(nd->data) indicate if MCA is recoverable */ if (kdump_on_fatal_mca && !(*(nd->data))) { if (atomic_inc_return(&kdump_in_progress) == 1) machine_kdump_on_init(); /* We got fatal MCA while kdump!? No way!! */ } break; } return NOTIFY_DONE; } #ifdef CONFIG_SYSCTL static ctl_table kdump_ctl_table[] = { { .procname = "kdump_on_init", .data = &kdump_on_init, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec, }, { .procname = "kdump_on_fatal_mca", .data = &kdump_on_fatal_mca, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec, }, { } }; static ctl_table sys_table[] = { { .procname = "kernel", .mode = 0555, .child = kdump_ctl_table, }, { } }; #endif static int machine_crash_setup(void) { /* be notified before default_monarch_init_process */ static struct notifier_block kdump_init_notifier_nb = { .notifier_call = kdump_init_notifier, .priority = 1, }; int ret; if((ret = register_die_notifier(&kdump_init_notifier_nb)) != 0) return ret; #ifdef CONFIG_SYSCTL register_sysctl_table(sys_table); #endif return 0; } __initcall(machine_crash_setup);