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![Jan Beulich](/assets/img/avatar_default.png)
When panic_timeout is zero, suppress triggering a nested panic due to soft lockup detection. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
176 lines
4 KiB
C
176 lines
4 KiB
C
/*
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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/config.h>
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#include <linux/module.h>
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#include <linux/sched.h>
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#include <linux/delay.h>
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#include <linux/reboot.h>
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#include <linux/notifier.h>
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#include <linux/init.h>
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#include <linux/sysrq.h>
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#include <linux/interrupt.h>
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#include <linux/nmi.h>
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#include <linux/kexec.h>
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int panic_timeout;
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int panic_on_oops;
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int tainted;
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EXPORT_SYMBOL(panic_timeout);
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struct notifier_block *panic_notifier_list;
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EXPORT_SYMBOL(panic_notifier_list);
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static int __init panic_setup(char *str)
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{
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panic_timeout = simple_strtoul(str, NULL, 0);
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return 1;
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}
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__setup("panic=", panic_setup);
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static long no_blink(long time)
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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)(long time);
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EXPORT_SYMBOL(panic_blink);
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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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NORET_TYPE void panic(const char * fmt, ...)
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{
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long i;
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static char buf[1024];
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va_list args;
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#if defined(CONFIG_S390)
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unsigned long caller = (unsigned long) __builtin_return_address(0);
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#endif
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/*
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* It's possible to come here directly from a panic-assertion and not
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* 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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preempt_disable();
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bust_spinlocks(1);
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va_start(args, fmt);
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vsnprintf(buf, sizeof(buf), fmt, args);
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va_end(args);
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printk(KERN_EMERG "Kernel panic - not syncing: %s\n",buf);
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bust_spinlocks(0);
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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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* Do we want to call this before we try to display a message?
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*/
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crash_kexec(NULL);
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#ifdef CONFIG_SMP
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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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#endif
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notifier_call_chain(&panic_notifier_list, 0, buf);
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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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printk(KERN_EMERG "Rebooting in %d seconds..",panic_timeout);
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for (i = 0; i < panic_timeout*1000; ) {
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touch_nmi_watchdog();
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i += panic_blink(i);
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mdelay(1);
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i++;
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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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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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printk(KERN_EMERG "Press Stop-A (L1-A) 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(caller);
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#endif
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local_irq_enable();
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for (i = 0;;) {
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touch_softlockup_watchdog();
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i += panic_blink(i);
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mdelay(1);
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i++;
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}
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}
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EXPORT_SYMBOL(panic);
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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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* 'P' - Proprietary module has been loaded.
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* 'F' - Module has been forcibly loaded.
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* 'S' - SMP with CPUs not designed for SMP.
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* 'R' - User forced a module unload.
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* 'M' - Machine had a machine check experience.
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* 'B' - System has hit bad_page.
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*
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* The string is overwritten by the next call to print_taint().
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*/
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const char *print_tainted(void)
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{
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static char buf[20];
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if (tainted) {
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snprintf(buf, sizeof(buf), "Tainted: %c%c%c%c%c%c",
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tainted & TAINT_PROPRIETARY_MODULE ? 'P' : 'G',
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tainted & TAINT_FORCED_MODULE ? 'F' : ' ',
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tainted & TAINT_UNSAFE_SMP ? 'S' : ' ',
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tainted & TAINT_FORCED_RMMOD ? 'R' : ' ',
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tainted & TAINT_MACHINE_CHECK ? 'M' : ' ',
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tainted & TAINT_BAD_PAGE ? 'B' : ' ');
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}
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else
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snprintf(buf, sizeof(buf), "Not tainted");
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return(buf);
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}
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void add_taint(unsigned flag)
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{
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tainted |= flag;
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}
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EXPORT_SYMBOL(add_taint);
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