^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Architecture specific (PPC64) functions for kexec based crash dumps.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (C) 2005, IBM Corp.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * Created by: Haren Myneni
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/smp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/reboot.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/kexec.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/export.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/crash_dump.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/delay.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <linux/irq.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include <asm/processor.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #include <asm/machdep.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) #include <asm/kexec.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #include <asm/prom.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) #include <asm/smp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) #include <asm/setjmp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) #include <asm/debug.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) * The primary CPU waits a while for all secondary CPUs to enter. This is to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) * avoid sending an IPI if the secondary CPUs are entering
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) * crash_kexec_secondary on their own (eg via a system reset).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) * The secondary timeout has to be longer than the primary. Both timeouts are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) * in milliseconds.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) #define PRIMARY_TIMEOUT 500
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) #define SECONDARY_TIMEOUT 1000
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) #define IPI_TIMEOUT 10000
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) #define REAL_MODE_TIMEOUT 10000
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) static int time_to_dump;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) * crash_wake_offline should be set to 1 by platforms that intend to wake
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) * up offline cpus prior to jumping to a kdump kernel. Currently powernv
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) * sets it to 1, since we want to avoid things from happening when an
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) * offline CPU wakes up due to something like an HMI (malfunction error),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) * which propagates to all threads.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) int crash_wake_offline;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) #define CRASH_HANDLER_MAX 3
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) /* List of shutdown handles */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) static crash_shutdown_t crash_shutdown_handles[CRASH_HANDLER_MAX];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) static DEFINE_SPINLOCK(crash_handlers_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) static unsigned long crash_shutdown_buf[JMP_BUF_LEN];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) static int crash_shutdown_cpu = -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) static int handle_fault(struct pt_regs *regs)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) if (crash_shutdown_cpu == smp_processor_id())
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) longjmp(crash_shutdown_buf, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) #ifdef CONFIG_SMP
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) static atomic_t cpus_in_crash;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) void crash_ipi_callback(struct pt_regs *regs)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) static cpumask_t cpus_state_saved = CPU_MASK_NONE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) int cpu = smp_processor_id();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) hard_irq_disable();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) if (!cpumask_test_cpu(cpu, &cpus_state_saved)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) crash_save_cpu(regs, cpu);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) cpumask_set_cpu(cpu, &cpus_state_saved);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) atomic_inc(&cpus_in_crash);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) smp_mb__after_atomic();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) * Starting the kdump boot.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) * This barrier is needed to make sure that all CPUs are stopped.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) while (!time_to_dump)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) cpu_relax();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) if (ppc_md.kexec_cpu_down)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) ppc_md.kexec_cpu_down(1, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) #ifdef CONFIG_PPC64
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) kexec_smp_wait();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) for (;;); /* FIXME */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) /* NOTREACHED */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) static void crash_kexec_prepare_cpus(int cpu)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) unsigned int msecs;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) unsigned int ncpus = num_online_cpus() - 1;/* Excluding the panic cpu */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) int tries = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) int (*old_handler)(struct pt_regs *regs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) printk(KERN_EMERG "Sending IPI to other CPUs\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) if (crash_wake_offline)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) ncpus = num_present_cpus() - 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) crash_send_ipi(crash_ipi_callback);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) smp_wmb();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) again:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) * FIXME: Until we will have the way to stop other CPUs reliably,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) * the crash CPU will send an IPI and wait for other CPUs to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) * respond.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) msecs = IPI_TIMEOUT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) while ((atomic_read(&cpus_in_crash) < ncpus) && (--msecs > 0))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) mdelay(1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) /* Would it be better to replace the trap vector here? */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) if (atomic_read(&cpus_in_crash) >= ncpus) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) printk(KERN_EMERG "IPI complete\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) printk(KERN_EMERG "ERROR: %d cpu(s) not responding\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) ncpus - atomic_read(&cpus_in_crash));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) * If we have a panic timeout set then we can't wait indefinitely
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) * for someone to activate system reset. We also give up on the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) * second time through if system reset fail to work.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) if ((panic_timeout > 0) || (tries > 0))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) * A system reset will cause all CPUs to take an 0x100 exception.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) * The primary CPU returns here via setjmp, and the secondary
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) * CPUs reexecute the crash_kexec_secondary path.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) old_handler = __debugger;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) __debugger = handle_fault;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) crash_shutdown_cpu = smp_processor_id();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) if (setjmp(crash_shutdown_buf) == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) printk(KERN_EMERG "Activate system reset (dumprestart) "
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) "to stop other cpu(s)\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) * A system reset will force all CPUs to execute the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) * crash code again. We need to reset cpus_in_crash so we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) * wait for everyone to do this.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) atomic_set(&cpus_in_crash, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) smp_mb();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) while (atomic_read(&cpus_in_crash) < ncpus)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) cpu_relax();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) crash_shutdown_cpu = -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) __debugger = old_handler;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) tries++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) goto again;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) * This function will be called by secondary cpus.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) void crash_kexec_secondary(struct pt_regs *regs)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) unsigned long flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) int msecs = SECONDARY_TIMEOUT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) local_irq_save(flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) /* Wait for the primary crash CPU to signal its progress */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) while (crashing_cpu < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) if (--msecs < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) /* No response, kdump image may not have been loaded */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) local_irq_restore(flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) mdelay(1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) crash_ipi_callback(regs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) #else /* ! CONFIG_SMP */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) static void crash_kexec_prepare_cpus(int cpu)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) * move the secondaries to us so that we can copy
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) * the new kernel 0-0x100 safely
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) * do this if kexec in setup.c ?
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) #ifdef CONFIG_PPC64
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) smp_release_cpus();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) /* FIXME */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) void crash_kexec_secondary(struct pt_regs *regs)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) #endif /* CONFIG_SMP */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) /* wait for all the CPUs to hit real mode but timeout if they don't come in */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) #if defined(CONFIG_SMP) && defined(CONFIG_PPC64)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) static void __maybe_unused crash_kexec_wait_realmode(int cpu)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) unsigned int msecs;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) msecs = REAL_MODE_TIMEOUT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) for (i=0; i < nr_cpu_ids && msecs > 0; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) if (i == cpu)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) while (paca_ptrs[i]->kexec_state < KEXEC_STATE_REAL_MODE) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) barrier();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) if (!cpu_possible(i) || !cpu_online(i) || (msecs <= 0))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) msecs--;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) mdelay(1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) mb();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) static inline void crash_kexec_wait_realmode(int cpu) {}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) #endif /* CONFIG_SMP && CONFIG_PPC64 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) * Register a function to be called on shutdown. Only use this if you
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) * can't reset your device in the second kernel.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) int crash_shutdown_register(crash_shutdown_t handler)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) unsigned int i, rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) spin_lock(&crash_handlers_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) for (i = 0 ; i < CRASH_HANDLER_MAX; i++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) if (!crash_shutdown_handles[i]) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) /* Insert handle at first empty entry */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) crash_shutdown_handles[i] = handler;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) rc = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) if (i == CRASH_HANDLER_MAX) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) printk(KERN_ERR "Crash shutdown handles full, "
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) "not registered.\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) rc = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) spin_unlock(&crash_handlers_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) EXPORT_SYMBOL(crash_shutdown_register);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) int crash_shutdown_unregister(crash_shutdown_t handler)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) unsigned int i, rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) spin_lock(&crash_handlers_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) for (i = 0 ; i < CRASH_HANDLER_MAX; i++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) if (crash_shutdown_handles[i] == handler)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) if (i == CRASH_HANDLER_MAX) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) printk(KERN_ERR "Crash shutdown handle not found\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) rc = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) /* Shift handles down */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) for (; i < (CRASH_HANDLER_MAX - 1); i++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) crash_shutdown_handles[i] =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) crash_shutdown_handles[i+1];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) * Reset last entry to NULL now that it has been shifted down,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) * this will allow new handles to be added here.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) crash_shutdown_handles[i] = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) rc = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) spin_unlock(&crash_handlers_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) EXPORT_SYMBOL(crash_shutdown_unregister);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) void default_machine_crash_shutdown(struct pt_regs *regs)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) unsigned int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) int (*old_handler)(struct pt_regs *regs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) /* Avoid hardlocking with irresponsive CPU holding logbuf_lock */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) printk_nmi_enter();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) * This function is only called after the system
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) * has panicked or is otherwise in a critical state.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) * The minimum amount of code to allow a kexec'd kernel
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) * to run successfully needs to happen here.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) * In practice this means stopping other cpus in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) * an SMP system.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) * The kernel is broken so disable interrupts.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) hard_irq_disable();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) * Make a note of crashing cpu. Will be used in machine_kexec
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) * such that another IPI will not be sent.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) crashing_cpu = smp_processor_id();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) * If we came in via system reset, wait a while for the secondary
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) * CPUs to enter.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) if (TRAP(regs) == 0x100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) mdelay(PRIMARY_TIMEOUT);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) crash_kexec_prepare_cpus(crashing_cpu);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) crash_save_cpu(regs, crashing_cpu);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) time_to_dump = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) crash_kexec_wait_realmode(crashing_cpu);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) machine_kexec_mask_interrupts();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) * Call registered shutdown routines safely. Swap out
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) * __debugger_fault_handler, and replace on exit.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) old_handler = __debugger_fault_handler;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) __debugger_fault_handler = handle_fault;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) crash_shutdown_cpu = smp_processor_id();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) for (i = 0; i < CRASH_HANDLER_MAX && crash_shutdown_handles[i]; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) if (setjmp(crash_shutdown_buf) == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) * Insert syncs and delay to ensure
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) * instructions in the dangerous region don't
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) * leak away from this protected region.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) asm volatile("sync; isync");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) /* dangerous region */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) crash_shutdown_handles[i]();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) asm volatile("sync; isync");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) crash_shutdown_cpu = -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) __debugger_fault_handler = old_handler;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) if (ppc_md.kexec_cpu_down)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) ppc_md.kexec_cpu_down(1, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) }
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
3 Commits
0 Branches
0 Tags