--- /dev/null
+/*
+ * arch/ia64/kernel/crash.c
+ *
+ * Architecture specific (ia64) functions for kexec based crash dumps.
+ *
+ * Created by: Khalid Aziz <khalid.aziz@hp.com>
+ * Copyright (C) 2005 Hewlett-Packard Development Company, L.P.
+ * Copyright (C) 2005 Intel Corp Zou Nan hai <nanhai.zou@intel.com>
+ *
+ */
+#include <linux/smp.h>
+#include <linux/delay.h>
+#include <linux/crash_dump.h>
+#include <linux/bootmem.h>
+#include <linux/kexec.h>
+#include <linux/elfcore.h>
+#include <linux/sysctl.h>
+#include <linux/init.h>
+#include <linux/kdebug.h>
+
+#include <asm/mca.h>
+
+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 struct 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 struct 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);
+
Code Review / kvmfornfv.git / blobdiff