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27dea14c7f
In preparation for improving objtool's handling of weak noreturn functions, mark nmi_panic_self_stop() __noreturn. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/316fc6dfab5a8c4e024c7185484a1ee5fb0afb79.1681342859.git.jpoimboe@kernel.org
809 lines
20 KiB
C
809 lines
20 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* linux/kernel/panic.c
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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*/
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/*
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* This function is used through-out the kernel (including mm and fs)
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* to indicate a major problem.
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*/
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#include <linux/debug_locks.h>
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#include <linux/sched/debug.h>
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#include <linux/interrupt.h>
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#include <linux/kgdb.h>
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#include <linux/kmsg_dump.h>
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#include <linux/kallsyms.h>
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#include <linux/notifier.h>
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#include <linux/vt_kern.h>
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#include <linux/module.h>
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#include <linux/random.h>
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#include <linux/ftrace.h>
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#include <linux/reboot.h>
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#include <linux/delay.h>
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#include <linux/kexec.h>
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#include <linux/panic_notifier.h>
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#include <linux/sched.h>
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#include <linux/string_helpers.h>
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#include <linux/sysrq.h>
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#include <linux/init.h>
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#include <linux/nmi.h>
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#include <linux/console.h>
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#include <linux/bug.h>
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#include <linux/ratelimit.h>
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#include <linux/debugfs.h>
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#include <linux/sysfs.h>
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#include <linux/context_tracking.h>
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#include <trace/events/error_report.h>
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#include <asm/sections.h>
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#define PANIC_TIMER_STEP 100
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#define PANIC_BLINK_SPD 18
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#ifdef CONFIG_SMP
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/*
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* Should we dump all CPUs backtraces in an oops event?
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* Defaults to 0, can be changed via sysctl.
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*/
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static unsigned int __read_mostly sysctl_oops_all_cpu_backtrace;
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#else
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#define sysctl_oops_all_cpu_backtrace 0
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#endif /* CONFIG_SMP */
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int panic_on_oops = CONFIG_PANIC_ON_OOPS_VALUE;
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static unsigned long tainted_mask =
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IS_ENABLED(CONFIG_RANDSTRUCT) ? (1 << TAINT_RANDSTRUCT) : 0;
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static int pause_on_oops;
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static int pause_on_oops_flag;
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static DEFINE_SPINLOCK(pause_on_oops_lock);
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bool crash_kexec_post_notifiers;
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int panic_on_warn __read_mostly;
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unsigned long panic_on_taint;
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bool panic_on_taint_nousertaint = false;
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static unsigned int warn_limit __read_mostly;
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int panic_timeout = CONFIG_PANIC_TIMEOUT;
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EXPORT_SYMBOL_GPL(panic_timeout);
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#define PANIC_PRINT_TASK_INFO 0x00000001
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#define PANIC_PRINT_MEM_INFO 0x00000002
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#define PANIC_PRINT_TIMER_INFO 0x00000004
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#define PANIC_PRINT_LOCK_INFO 0x00000008
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#define PANIC_PRINT_FTRACE_INFO 0x00000010
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#define PANIC_PRINT_ALL_PRINTK_MSG 0x00000020
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#define PANIC_PRINT_ALL_CPU_BT 0x00000040
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unsigned long panic_print;
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ATOMIC_NOTIFIER_HEAD(panic_notifier_list);
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EXPORT_SYMBOL(panic_notifier_list);
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#ifdef CONFIG_SYSCTL
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static struct ctl_table kern_panic_table[] = {
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#ifdef CONFIG_SMP
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{
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.procname = "oops_all_cpu_backtrace",
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.data = &sysctl_oops_all_cpu_backtrace,
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.maxlen = sizeof(int),
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.mode = 0644,
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.proc_handler = proc_dointvec_minmax,
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.extra1 = SYSCTL_ZERO,
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.extra2 = SYSCTL_ONE,
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},
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#endif
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{
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.procname = "warn_limit",
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.data = &warn_limit,
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.maxlen = sizeof(warn_limit),
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.mode = 0644,
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.proc_handler = proc_douintvec,
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},
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{ }
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};
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static __init int kernel_panic_sysctls_init(void)
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{
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register_sysctl_init("kernel", kern_panic_table);
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return 0;
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}
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late_initcall(kernel_panic_sysctls_init);
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#endif
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static atomic_t warn_count = ATOMIC_INIT(0);
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#ifdef CONFIG_SYSFS
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static ssize_t warn_count_show(struct kobject *kobj, struct kobj_attribute *attr,
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char *page)
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{
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return sysfs_emit(page, "%d\n", atomic_read(&warn_count));
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}
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static struct kobj_attribute warn_count_attr = __ATTR_RO(warn_count);
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static __init int kernel_panic_sysfs_init(void)
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{
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sysfs_add_file_to_group(kernel_kobj, &warn_count_attr.attr, NULL);
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return 0;
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}
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late_initcall(kernel_panic_sysfs_init);
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#endif
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static long no_blink(int state)
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{
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return 0;
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}
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/* Returns how long it waited in ms */
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long (*panic_blink)(int state);
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EXPORT_SYMBOL(panic_blink);
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/*
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* Stop ourself in panic -- architecture code may override this
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*/
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void __weak __noreturn panic_smp_self_stop(void)
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{
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while (1)
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cpu_relax();
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}
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/*
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* Stop ourselves in NMI context if another CPU has already panicked. Arch code
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* may override this to prepare for crash dumping, e.g. save regs info.
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*/
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void __weak __noreturn nmi_panic_self_stop(struct pt_regs *regs)
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{
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panic_smp_self_stop();
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}
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/*
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* Stop other CPUs in panic. Architecture dependent code may override this
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* with more suitable version. For example, if the architecture supports
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* crash dump, it should save registers of each stopped CPU and disable
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* per-CPU features such as virtualization extensions.
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*/
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void __weak crash_smp_send_stop(void)
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{
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static int cpus_stopped;
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/*
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* This function can be called twice in panic path, but obviously
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* we execute this only once.
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*/
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if (cpus_stopped)
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return;
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/*
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* Note smp_send_stop is the usual smp shutdown function, which
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* unfortunately means it may not be hardened to work in a panic
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* situation.
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*/
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smp_send_stop();
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cpus_stopped = 1;
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}
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atomic_t panic_cpu = ATOMIC_INIT(PANIC_CPU_INVALID);
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/*
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* A variant of panic() called from NMI context. We return if we've already
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* panicked on this CPU. If another CPU already panicked, loop in
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* nmi_panic_self_stop() which can provide architecture dependent code such
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* as saving register state for crash dump.
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*/
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void nmi_panic(struct pt_regs *regs, const char *msg)
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{
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int old_cpu, cpu;
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cpu = raw_smp_processor_id();
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old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, cpu);
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if (old_cpu == PANIC_CPU_INVALID)
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panic("%s", msg);
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else if (old_cpu != cpu)
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nmi_panic_self_stop(regs);
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}
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EXPORT_SYMBOL(nmi_panic);
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static void panic_print_sys_info(bool console_flush)
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{
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if (console_flush) {
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if (panic_print & PANIC_PRINT_ALL_PRINTK_MSG)
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console_flush_on_panic(CONSOLE_REPLAY_ALL);
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return;
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}
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if (panic_print & PANIC_PRINT_TASK_INFO)
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show_state();
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if (panic_print & PANIC_PRINT_MEM_INFO)
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show_mem(0, NULL);
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if (panic_print & PANIC_PRINT_TIMER_INFO)
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sysrq_timer_list_show();
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if (panic_print & PANIC_PRINT_LOCK_INFO)
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debug_show_all_locks();
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if (panic_print & PANIC_PRINT_FTRACE_INFO)
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ftrace_dump(DUMP_ALL);
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}
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void check_panic_on_warn(const char *origin)
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{
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unsigned int limit;
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if (panic_on_warn)
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panic("%s: panic_on_warn set ...\n", origin);
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limit = READ_ONCE(warn_limit);
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if (atomic_inc_return(&warn_count) >= limit && limit)
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panic("%s: system warned too often (kernel.warn_limit is %d)",
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origin, limit);
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}
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/*
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* Helper that triggers the NMI backtrace (if set in panic_print)
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* and then performs the secondary CPUs shutdown - we cannot have
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* the NMI backtrace after the CPUs are off!
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*/
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static void panic_other_cpus_shutdown(bool crash_kexec)
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{
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if (panic_print & PANIC_PRINT_ALL_CPU_BT)
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trigger_all_cpu_backtrace();
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/*
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* Note that smp_send_stop() is the usual SMP shutdown function,
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* which unfortunately may not be hardened to work in a panic
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* situation. If we want to do crash dump after notifier calls
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* and kmsg_dump, we will need architecture dependent extra
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* bits in addition to stopping other CPUs, hence we rely on
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* crash_smp_send_stop() for that.
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*/
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if (!crash_kexec)
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smp_send_stop();
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else
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crash_smp_send_stop();
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}
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/**
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* panic - halt the system
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* @fmt: The text string to print
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*
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* Display a message, then perform cleanups.
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*
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* This function never returns.
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*/
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void panic(const char *fmt, ...)
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{
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static char buf[1024];
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va_list args;
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long i, i_next = 0, len;
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int state = 0;
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int old_cpu, this_cpu;
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bool _crash_kexec_post_notifiers = crash_kexec_post_notifiers;
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if (panic_on_warn) {
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/*
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* This thread may hit another WARN() in the panic path.
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* Resetting this prevents additional WARN() from panicking the
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* system on this thread. Other threads are blocked by the
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* panic_mutex in panic().
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*/
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panic_on_warn = 0;
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}
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/*
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* Disable local interrupts. This will prevent panic_smp_self_stop
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* from deadlocking the first cpu that invokes the panic, since
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* there is nothing to prevent an interrupt handler (that runs
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* after setting panic_cpu) from invoking panic() again.
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*/
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local_irq_disable();
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preempt_disable_notrace();
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/*
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* It's possible to come here directly from a panic-assertion and
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* not have preempt disabled. Some functions called from here want
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* preempt to be disabled. No point enabling it later though...
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*
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* Only one CPU is allowed to execute the panic code from here. For
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* multiple parallel invocations of panic, all other CPUs either
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* stop themself or will wait until they are stopped by the 1st CPU
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* with smp_send_stop().
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*
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* `old_cpu == PANIC_CPU_INVALID' means this is the 1st CPU which
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* comes here, so go ahead.
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* `old_cpu == this_cpu' means we came from nmi_panic() which sets
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* panic_cpu to this CPU. In this case, this is also the 1st CPU.
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*/
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this_cpu = raw_smp_processor_id();
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old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, this_cpu);
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if (old_cpu != PANIC_CPU_INVALID && old_cpu != this_cpu)
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panic_smp_self_stop();
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console_verbose();
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bust_spinlocks(1);
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va_start(args, fmt);
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len = vscnprintf(buf, sizeof(buf), fmt, args);
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va_end(args);
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if (len && buf[len - 1] == '\n')
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buf[len - 1] = '\0';
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pr_emerg("Kernel panic - not syncing: %s\n", buf);
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#ifdef CONFIG_DEBUG_BUGVERBOSE
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/*
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* Avoid nested stack-dumping if a panic occurs during oops processing
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*/
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if (!test_taint(TAINT_DIE) && oops_in_progress <= 1)
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dump_stack();
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#endif
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/*
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* If kgdb is enabled, give it a chance to run before we stop all
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* the other CPUs or else we won't be able to debug processes left
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* running on them.
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*/
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kgdb_panic(buf);
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/*
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* If we have crashed and we have a crash kernel loaded let it handle
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* everything else.
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* If we want to run this after calling panic_notifiers, pass
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* the "crash_kexec_post_notifiers" option to the kernel.
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*
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* Bypass the panic_cpu check and call __crash_kexec directly.
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*/
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if (!_crash_kexec_post_notifiers)
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__crash_kexec(NULL);
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panic_other_cpus_shutdown(_crash_kexec_post_notifiers);
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/*
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* Run any panic handlers, including those that might need to
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* add information to the kmsg dump output.
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*/
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atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
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panic_print_sys_info(false);
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kmsg_dump(KMSG_DUMP_PANIC);
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/*
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* If you doubt kdump always works fine in any situation,
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* "crash_kexec_post_notifiers" offers you a chance to run
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* panic_notifiers and dumping kmsg before kdump.
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* Note: since some panic_notifiers can make crashed kernel
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* more unstable, it can increase risks of the kdump failure too.
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*
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* Bypass the panic_cpu check and call __crash_kexec directly.
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*/
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if (_crash_kexec_post_notifiers)
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__crash_kexec(NULL);
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console_unblank();
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/*
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* We may have ended up stopping the CPU holding the lock (in
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* smp_send_stop()) while still having some valuable data in the console
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* buffer. Try to acquire the lock then release it regardless of the
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* result. The release will also print the buffers out. Locks debug
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* should be disabled to avoid reporting bad unlock balance when
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* panic() is not being callled from OOPS.
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*/
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debug_locks_off();
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console_flush_on_panic(CONSOLE_FLUSH_PENDING);
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panic_print_sys_info(true);
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if (!panic_blink)
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panic_blink = no_blink;
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if (panic_timeout > 0) {
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/*
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* Delay timeout seconds before rebooting the machine.
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* We can't use the "normal" timers since we just panicked.
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*/
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pr_emerg("Rebooting in %d seconds..\n", panic_timeout);
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for (i = 0; i < panic_timeout * 1000; i += PANIC_TIMER_STEP) {
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touch_nmi_watchdog();
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if (i >= i_next) {
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i += panic_blink(state ^= 1);
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i_next = i + 3600 / PANIC_BLINK_SPD;
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}
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mdelay(PANIC_TIMER_STEP);
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}
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}
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if (panic_timeout != 0) {
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/*
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* This will not be a clean reboot, with everything
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* shutting down. But if there is a chance of
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* rebooting the system it will be rebooted.
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*/
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if (panic_reboot_mode != REBOOT_UNDEFINED)
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reboot_mode = panic_reboot_mode;
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emergency_restart();
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}
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#ifdef __sparc__
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{
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extern int stop_a_enabled;
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/* Make sure the user can actually press Stop-A (L1-A) */
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stop_a_enabled = 1;
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pr_emerg("Press Stop-A (L1-A) from sun keyboard or send break\n"
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"twice on console to return to the boot prom\n");
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}
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#endif
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#if defined(CONFIG_S390)
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disabled_wait();
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#endif
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pr_emerg("---[ end Kernel panic - not syncing: %s ]---\n", buf);
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/* Do not scroll important messages printed above */
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suppress_printk = 1;
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local_irq_enable();
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for (i = 0; ; i += PANIC_TIMER_STEP) {
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touch_softlockup_watchdog();
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if (i >= i_next) {
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i += panic_blink(state ^= 1);
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i_next = i + 3600 / PANIC_BLINK_SPD;
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}
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mdelay(PANIC_TIMER_STEP);
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}
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}
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EXPORT_SYMBOL(panic);
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/*
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* TAINT_FORCED_RMMOD could be a per-module flag but the module
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* is being removed anyway.
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*/
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const struct taint_flag taint_flags[TAINT_FLAGS_COUNT] = {
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[ TAINT_PROPRIETARY_MODULE ] = { 'P', 'G', true },
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[ TAINT_FORCED_MODULE ] = { 'F', ' ', true },
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[ TAINT_CPU_OUT_OF_SPEC ] = { 'S', ' ', false },
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[ TAINT_FORCED_RMMOD ] = { 'R', ' ', false },
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[ TAINT_MACHINE_CHECK ] = { 'M', ' ', false },
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[ TAINT_BAD_PAGE ] = { 'B', ' ', false },
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[ TAINT_USER ] = { 'U', ' ', false },
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[ TAINT_DIE ] = { 'D', ' ', false },
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[ TAINT_OVERRIDDEN_ACPI_TABLE ] = { 'A', ' ', false },
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[ TAINT_WARN ] = { 'W', ' ', false },
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[ TAINT_CRAP ] = { 'C', ' ', true },
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[ TAINT_FIRMWARE_WORKAROUND ] = { 'I', ' ', false },
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[ TAINT_OOT_MODULE ] = { 'O', ' ', true },
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[ TAINT_UNSIGNED_MODULE ] = { 'E', ' ', true },
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[ TAINT_SOFTLOCKUP ] = { 'L', ' ', false },
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[ TAINT_LIVEPATCH ] = { 'K', ' ', true },
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[ TAINT_AUX ] = { 'X', ' ', true },
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[ TAINT_RANDSTRUCT ] = { 'T', ' ', true },
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[ TAINT_TEST ] = { 'N', ' ', true },
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};
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/**
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* print_tainted - return a string to represent the kernel taint state.
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*
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* For individual taint flag meanings, see Documentation/admin-guide/sysctl/kernel.rst
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*
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* The string is overwritten by the next call to print_tainted(),
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* but is always NULL terminated.
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*/
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|
const char *print_tainted(void)
|
|
{
|
|
static char buf[TAINT_FLAGS_COUNT + sizeof("Tainted: ")];
|
|
|
|
BUILD_BUG_ON(ARRAY_SIZE(taint_flags) != TAINT_FLAGS_COUNT);
|
|
|
|
if (tainted_mask) {
|
|
char *s;
|
|
int i;
|
|
|
|
s = buf + sprintf(buf, "Tainted: ");
|
|
for (i = 0; i < TAINT_FLAGS_COUNT; i++) {
|
|
const struct taint_flag *t = &taint_flags[i];
|
|
*s++ = test_bit(i, &tainted_mask) ?
|
|
t->c_true : t->c_false;
|
|
}
|
|
*s = 0;
|
|
} else
|
|
snprintf(buf, sizeof(buf), "Not tainted");
|
|
|
|
return buf;
|
|
}
|
|
|
|
int test_taint(unsigned flag)
|
|
{
|
|
return test_bit(flag, &tainted_mask);
|
|
}
|
|
EXPORT_SYMBOL(test_taint);
|
|
|
|
unsigned long get_taint(void)
|
|
{
|
|
return tainted_mask;
|
|
}
|
|
|
|
/**
|
|
* add_taint: add a taint flag if not already set.
|
|
* @flag: one of the TAINT_* constants.
|
|
* @lockdep_ok: whether lock debugging is still OK.
|
|
*
|
|
* If something bad has gone wrong, you'll want @lockdebug_ok = false, but for
|
|
* some notewortht-but-not-corrupting cases, it can be set to true.
|
|
*/
|
|
void add_taint(unsigned flag, enum lockdep_ok lockdep_ok)
|
|
{
|
|
if (lockdep_ok == LOCKDEP_NOW_UNRELIABLE && __debug_locks_off())
|
|
pr_warn("Disabling lock debugging due to kernel taint\n");
|
|
|
|
set_bit(flag, &tainted_mask);
|
|
|
|
if (tainted_mask & panic_on_taint) {
|
|
panic_on_taint = 0;
|
|
panic("panic_on_taint set ...");
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(add_taint);
|
|
|
|
static void spin_msec(int msecs)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < msecs; i++) {
|
|
touch_nmi_watchdog();
|
|
mdelay(1);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* It just happens that oops_enter() and oops_exit() are identically
|
|
* implemented...
|
|
*/
|
|
static void do_oops_enter_exit(void)
|
|
{
|
|
unsigned long flags;
|
|
static int spin_counter;
|
|
|
|
if (!pause_on_oops)
|
|
return;
|
|
|
|
spin_lock_irqsave(&pause_on_oops_lock, flags);
|
|
if (pause_on_oops_flag == 0) {
|
|
/* This CPU may now print the oops message */
|
|
pause_on_oops_flag = 1;
|
|
} else {
|
|
/* We need to stall this CPU */
|
|
if (!spin_counter) {
|
|
/* This CPU gets to do the counting */
|
|
spin_counter = pause_on_oops;
|
|
do {
|
|
spin_unlock(&pause_on_oops_lock);
|
|
spin_msec(MSEC_PER_SEC);
|
|
spin_lock(&pause_on_oops_lock);
|
|
} while (--spin_counter);
|
|
pause_on_oops_flag = 0;
|
|
} else {
|
|
/* This CPU waits for a different one */
|
|
while (spin_counter) {
|
|
spin_unlock(&pause_on_oops_lock);
|
|
spin_msec(1);
|
|
spin_lock(&pause_on_oops_lock);
|
|
}
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&pause_on_oops_lock, flags);
|
|
}
|
|
|
|
/*
|
|
* Return true if the calling CPU is allowed to print oops-related info.
|
|
* This is a bit racy..
|
|
*/
|
|
bool oops_may_print(void)
|
|
{
|
|
return pause_on_oops_flag == 0;
|
|
}
|
|
|
|
/*
|
|
* Called when the architecture enters its oops handler, before it prints
|
|
* anything. If this is the first CPU to oops, and it's oopsing the first
|
|
* time then let it proceed.
|
|
*
|
|
* This is all enabled by the pause_on_oops kernel boot option. We do all
|
|
* this to ensure that oopses don't scroll off the screen. It has the
|
|
* side-effect of preventing later-oopsing CPUs from mucking up the display,
|
|
* too.
|
|
*
|
|
* It turns out that the CPU which is allowed to print ends up pausing for
|
|
* the right duration, whereas all the other CPUs pause for twice as long:
|
|
* once in oops_enter(), once in oops_exit().
|
|
*/
|
|
void oops_enter(void)
|
|
{
|
|
tracing_off();
|
|
/* can't trust the integrity of the kernel anymore: */
|
|
debug_locks_off();
|
|
do_oops_enter_exit();
|
|
|
|
if (sysctl_oops_all_cpu_backtrace)
|
|
trigger_all_cpu_backtrace();
|
|
}
|
|
|
|
static void print_oops_end_marker(void)
|
|
{
|
|
pr_warn("---[ end trace %016llx ]---\n", 0ULL);
|
|
}
|
|
|
|
/*
|
|
* Called when the architecture exits its oops handler, after printing
|
|
* everything.
|
|
*/
|
|
void oops_exit(void)
|
|
{
|
|
do_oops_enter_exit();
|
|
print_oops_end_marker();
|
|
kmsg_dump(KMSG_DUMP_OOPS);
|
|
}
|
|
|
|
struct warn_args {
|
|
const char *fmt;
|
|
va_list args;
|
|
};
|
|
|
|
void __warn(const char *file, int line, void *caller, unsigned taint,
|
|
struct pt_regs *regs, struct warn_args *args)
|
|
{
|
|
disable_trace_on_warning();
|
|
|
|
if (file)
|
|
pr_warn("WARNING: CPU: %d PID: %d at %s:%d %pS\n",
|
|
raw_smp_processor_id(), current->pid, file, line,
|
|
caller);
|
|
else
|
|
pr_warn("WARNING: CPU: %d PID: %d at %pS\n",
|
|
raw_smp_processor_id(), current->pid, caller);
|
|
|
|
if (args)
|
|
vprintk(args->fmt, args->args);
|
|
|
|
print_modules();
|
|
|
|
if (regs)
|
|
show_regs(regs);
|
|
|
|
check_panic_on_warn("kernel");
|
|
|
|
if (!regs)
|
|
dump_stack();
|
|
|
|
print_irqtrace_events(current);
|
|
|
|
print_oops_end_marker();
|
|
trace_error_report_end(ERROR_DETECTOR_WARN, (unsigned long)caller);
|
|
|
|
/* Just a warning, don't kill lockdep. */
|
|
add_taint(taint, LOCKDEP_STILL_OK);
|
|
}
|
|
|
|
#ifndef __WARN_FLAGS
|
|
void warn_slowpath_fmt(const char *file, int line, unsigned taint,
|
|
const char *fmt, ...)
|
|
{
|
|
bool rcu = warn_rcu_enter();
|
|
struct warn_args args;
|
|
|
|
pr_warn(CUT_HERE);
|
|
|
|
if (!fmt) {
|
|
__warn(file, line, __builtin_return_address(0), taint,
|
|
NULL, NULL);
|
|
return;
|
|
}
|
|
|
|
args.fmt = fmt;
|
|
va_start(args.args, fmt);
|
|
__warn(file, line, __builtin_return_address(0), taint, NULL, &args);
|
|
va_end(args.args);
|
|
warn_rcu_exit(rcu);
|
|
}
|
|
EXPORT_SYMBOL(warn_slowpath_fmt);
|
|
#else
|
|
void __warn_printk(const char *fmt, ...)
|
|
{
|
|
bool rcu = warn_rcu_enter();
|
|
va_list args;
|
|
|
|
pr_warn(CUT_HERE);
|
|
|
|
va_start(args, fmt);
|
|
vprintk(fmt, args);
|
|
va_end(args);
|
|
warn_rcu_exit(rcu);
|
|
}
|
|
EXPORT_SYMBOL(__warn_printk);
|
|
#endif
|
|
|
|
#ifdef CONFIG_BUG
|
|
|
|
/* Support resetting WARN*_ONCE state */
|
|
|
|
static int clear_warn_once_set(void *data, u64 val)
|
|
{
|
|
generic_bug_clear_once();
|
|
memset(__start_once, 0, __end_once - __start_once);
|
|
return 0;
|
|
}
|
|
|
|
DEFINE_DEBUGFS_ATTRIBUTE(clear_warn_once_fops, NULL, clear_warn_once_set,
|
|
"%lld\n");
|
|
|
|
static __init int register_warn_debugfs(void)
|
|
{
|
|
/* Don't care about failure */
|
|
debugfs_create_file_unsafe("clear_warn_once", 0200, NULL, NULL,
|
|
&clear_warn_once_fops);
|
|
return 0;
|
|
}
|
|
|
|
device_initcall(register_warn_debugfs);
|
|
#endif
|
|
|
|
#ifdef CONFIG_STACKPROTECTOR
|
|
|
|
/*
|
|
* Called when gcc's -fstack-protector feature is used, and
|
|
* gcc detects corruption of the on-stack canary value
|
|
*/
|
|
__visible noinstr void __stack_chk_fail(void)
|
|
{
|
|
instrumentation_begin();
|
|
panic("stack-protector: Kernel stack is corrupted in: %pB",
|
|
__builtin_return_address(0));
|
|
instrumentation_end();
|
|
}
|
|
EXPORT_SYMBOL(__stack_chk_fail);
|
|
|
|
#endif
|
|
|
|
core_param(panic, panic_timeout, int, 0644);
|
|
core_param(panic_print, panic_print, ulong, 0644);
|
|
core_param(pause_on_oops, pause_on_oops, int, 0644);
|
|
core_param(panic_on_warn, panic_on_warn, int, 0644);
|
|
core_param(crash_kexec_post_notifiers, crash_kexec_post_notifiers, bool, 0644);
|
|
|
|
static int __init oops_setup(char *s)
|
|
{
|
|
if (!s)
|
|
return -EINVAL;
|
|
if (!strcmp(s, "panic"))
|
|
panic_on_oops = 1;
|
|
return 0;
|
|
}
|
|
early_param("oops", oops_setup);
|
|
|
|
static int __init panic_on_taint_setup(char *s)
|
|
{
|
|
char *taint_str;
|
|
|
|
if (!s)
|
|
return -EINVAL;
|
|
|
|
taint_str = strsep(&s, ",");
|
|
if (kstrtoul(taint_str, 16, &panic_on_taint))
|
|
return -EINVAL;
|
|
|
|
/* make sure panic_on_taint doesn't hold out-of-range TAINT flags */
|
|
panic_on_taint &= TAINT_FLAGS_MAX;
|
|
|
|
if (!panic_on_taint)
|
|
return -EINVAL;
|
|
|
|
if (s && !strcmp(s, "nousertaint"))
|
|
panic_on_taint_nousertaint = true;
|
|
|
|
pr_info("panic_on_taint: bitmask=0x%lx nousertaint_mode=%s\n",
|
|
panic_on_taint, str_enabled_disabled(panic_on_taint_nousertaint));
|
|
|
|
return 0;
|
|
}
|
|
early_param("panic_on_taint", panic_on_taint_setup);
|