diff options
Diffstat (limited to 'arch/ia64/kernel/crash.c')
-rw-r--r-- | arch/ia64/kernel/crash.c | 257 |
1 files changed, 257 insertions, 0 deletions
diff --git a/arch/ia64/kernel/crash.c b/arch/ia64/kernel/crash.c new file mode 100644 index 0000000000..88b3ce3e66 --- /dev/null +++ b/arch/ia64/kernel/crash.c @@ -0,0 +1,257 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * 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/memblock.h> +#include <linux/kexec.h> +#include <linux/elfcore.h> +#include <linux/reboot.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; + +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->common.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; + fallthrough; + 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, + }, + { } +}; +#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("kernel", kdump_ctl_table); +#endif + return 0; +} + +__initcall(machine_crash_setup); + |