mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-05 10:36:42 +07:00
b460cbc581
is_init() is an ambiguous name for the pid==1 check. Split it into is_global_init() and is_container_init(). A cgroup init has it's tsk->pid == 1. A global init also has it's tsk->pid == 1 and it's active pid namespace is the init_pid_ns. But rather than check the active pid namespace, compare the task structure with 'init_pid_ns.child_reaper', which is initialized during boot to the /sbin/init process and never changes. Changelog: 2.6.22-rc4-mm2-pidns1: - Use 'init_pid_ns.child_reaper' to determine if a given task is the global init (/sbin/init) process. This would improve performance and remove dependence on the task_pid(). 2.6.21-mm2-pidns2: - [Sukadev Bhattiprolu] Changed is_container_init() calls in {powerpc, ppc,avr32}/traps.c for the _exception() call to is_global_init(). This way, we kill only the cgroup if the cgroup's init has a bug rather than force a kernel panic. [akpm@linux-foundation.org: fix comment] [sukadev@us.ibm.com: Use is_global_init() in arch/m32r/mm/fault.c] [bunk@stusta.de: kernel/pid.c: remove unused exports] [sukadev@us.ibm.com: Fix capability.c to work with threaded init] Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Acked-by: Pavel Emelianov <xemul@openvz.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Herbert Poetzel <herbert@13thfloor.at> Cc: Kirill Korotaev <dev@sw.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
490 lines
12 KiB
C
490 lines
12 KiB
C
/* -*- linux-c -*-
|
|
*
|
|
* $Id: sysrq.c,v 1.15 1998/08/23 14:56:41 mj Exp $
|
|
*
|
|
* Linux Magic System Request Key Hacks
|
|
*
|
|
* (c) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
|
|
* based on ideas by Pavel Machek <pavel@atrey.karlin.mff.cuni.cz>
|
|
*
|
|
* (c) 2000 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
|
|
* overhauled to use key registration
|
|
* based upon discusions in irc://irc.openprojects.net/#kernelnewbies
|
|
*/
|
|
|
|
#include <linux/sched.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/tty.h>
|
|
#include <linux/mount.h>
|
|
#include <linux/kdev_t.h>
|
|
#include <linux/major.h>
|
|
#include <linux/reboot.h>
|
|
#include <linux/sysrq.h>
|
|
#include <linux/kbd_kern.h>
|
|
#include <linux/quotaops.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/suspend.h>
|
|
#include <linux/writeback.h>
|
|
#include <linux/buffer_head.h> /* for fsync_bdev() */
|
|
#include <linux/swap.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/vt_kern.h>
|
|
#include <linux/workqueue.h>
|
|
#include <linux/kexec.h>
|
|
#include <linux/irq.h>
|
|
#include <linux/hrtimer.h>
|
|
#include <linux/oom.h>
|
|
|
|
#include <asm/ptrace.h>
|
|
#include <asm/irq_regs.h>
|
|
|
|
/* Whether we react on sysrq keys or just ignore them */
|
|
int __read_mostly __sysrq_enabled = 1;
|
|
|
|
static int __read_mostly sysrq_always_enabled;
|
|
|
|
int sysrq_on(void)
|
|
{
|
|
return __sysrq_enabled || sysrq_always_enabled;
|
|
}
|
|
|
|
/*
|
|
* A value of 1 means 'all', other nonzero values are an op mask:
|
|
*/
|
|
static inline int sysrq_on_mask(int mask)
|
|
{
|
|
return sysrq_always_enabled || __sysrq_enabled == 1 ||
|
|
(__sysrq_enabled & mask);
|
|
}
|
|
|
|
static int __init sysrq_always_enabled_setup(char *str)
|
|
{
|
|
sysrq_always_enabled = 1;
|
|
printk(KERN_INFO "debug: sysrq always enabled.\n");
|
|
|
|
return 1;
|
|
}
|
|
|
|
__setup("sysrq_always_enabled", sysrq_always_enabled_setup);
|
|
|
|
|
|
static void sysrq_handle_loglevel(int key, struct tty_struct *tty)
|
|
{
|
|
int i;
|
|
i = key - '0';
|
|
console_loglevel = 7;
|
|
printk("Loglevel set to %d\n", i);
|
|
console_loglevel = i;
|
|
}
|
|
static struct sysrq_key_op sysrq_loglevel_op = {
|
|
.handler = sysrq_handle_loglevel,
|
|
.help_msg = "loglevel0-8",
|
|
.action_msg = "Changing Loglevel",
|
|
.enable_mask = SYSRQ_ENABLE_LOG,
|
|
};
|
|
|
|
#ifdef CONFIG_VT
|
|
static void sysrq_handle_SAK(int key, struct tty_struct *tty)
|
|
{
|
|
struct work_struct *SAK_work = &vc_cons[fg_console].SAK_work;
|
|
schedule_work(SAK_work);
|
|
}
|
|
static struct sysrq_key_op sysrq_SAK_op = {
|
|
.handler = sysrq_handle_SAK,
|
|
.help_msg = "saK",
|
|
.action_msg = "SAK",
|
|
.enable_mask = SYSRQ_ENABLE_KEYBOARD,
|
|
};
|
|
#else
|
|
#define sysrq_SAK_op (*(struct sysrq_key_op *)0)
|
|
#endif
|
|
|
|
#ifdef CONFIG_VT
|
|
static void sysrq_handle_unraw(int key, struct tty_struct *tty)
|
|
{
|
|
struct kbd_struct *kbd = &kbd_table[fg_console];
|
|
|
|
if (kbd)
|
|
kbd->kbdmode = default_utf8 ? VC_UNICODE : VC_XLATE;
|
|
}
|
|
static struct sysrq_key_op sysrq_unraw_op = {
|
|
.handler = sysrq_handle_unraw,
|
|
.help_msg = "unRaw",
|
|
.action_msg = "Keyboard mode set to system default",
|
|
.enable_mask = SYSRQ_ENABLE_KEYBOARD,
|
|
};
|
|
#else
|
|
#define sysrq_unraw_op (*(struct sysrq_key_op *)0)
|
|
#endif /* CONFIG_VT */
|
|
|
|
#ifdef CONFIG_KEXEC
|
|
static void sysrq_handle_crashdump(int key, struct tty_struct *tty)
|
|
{
|
|
crash_kexec(get_irq_regs());
|
|
}
|
|
static struct sysrq_key_op sysrq_crashdump_op = {
|
|
.handler = sysrq_handle_crashdump,
|
|
.help_msg = "Crashdump",
|
|
.action_msg = "Trigger a crashdump",
|
|
.enable_mask = SYSRQ_ENABLE_DUMP,
|
|
};
|
|
#else
|
|
#define sysrq_crashdump_op (*(struct sysrq_key_op *)0)
|
|
#endif
|
|
|
|
static void sysrq_handle_reboot(int key, struct tty_struct *tty)
|
|
{
|
|
lockdep_off();
|
|
local_irq_enable();
|
|
emergency_restart();
|
|
}
|
|
static struct sysrq_key_op sysrq_reboot_op = {
|
|
.handler = sysrq_handle_reboot,
|
|
.help_msg = "reBoot",
|
|
.action_msg = "Resetting",
|
|
.enable_mask = SYSRQ_ENABLE_BOOT,
|
|
};
|
|
|
|
static void sysrq_handle_sync(int key, struct tty_struct *tty)
|
|
{
|
|
emergency_sync();
|
|
}
|
|
static struct sysrq_key_op sysrq_sync_op = {
|
|
.handler = sysrq_handle_sync,
|
|
.help_msg = "Sync",
|
|
.action_msg = "Emergency Sync",
|
|
.enable_mask = SYSRQ_ENABLE_SYNC,
|
|
};
|
|
|
|
static void sysrq_handle_show_timers(int key, struct tty_struct *tty)
|
|
{
|
|
sysrq_timer_list_show();
|
|
}
|
|
|
|
static struct sysrq_key_op sysrq_show_timers_op = {
|
|
.handler = sysrq_handle_show_timers,
|
|
.help_msg = "show-all-timers(Q)",
|
|
.action_msg = "Show Pending Timers",
|
|
};
|
|
|
|
static void sysrq_handle_mountro(int key, struct tty_struct *tty)
|
|
{
|
|
emergency_remount();
|
|
}
|
|
static struct sysrq_key_op sysrq_mountro_op = {
|
|
.handler = sysrq_handle_mountro,
|
|
.help_msg = "Unmount",
|
|
.action_msg = "Emergency Remount R/O",
|
|
.enable_mask = SYSRQ_ENABLE_REMOUNT,
|
|
};
|
|
|
|
#ifdef CONFIG_LOCKDEP
|
|
static void sysrq_handle_showlocks(int key, struct tty_struct *tty)
|
|
{
|
|
debug_show_all_locks();
|
|
}
|
|
|
|
static struct sysrq_key_op sysrq_showlocks_op = {
|
|
.handler = sysrq_handle_showlocks,
|
|
.help_msg = "show-all-locks(D)",
|
|
.action_msg = "Show Locks Held",
|
|
};
|
|
#else
|
|
#define sysrq_showlocks_op (*(struct sysrq_key_op *)0)
|
|
#endif
|
|
|
|
static void sysrq_handle_showregs(int key, struct tty_struct *tty)
|
|
{
|
|
struct pt_regs *regs = get_irq_regs();
|
|
if (regs)
|
|
show_regs(regs);
|
|
}
|
|
static struct sysrq_key_op sysrq_showregs_op = {
|
|
.handler = sysrq_handle_showregs,
|
|
.help_msg = "showPc",
|
|
.action_msg = "Show Regs",
|
|
.enable_mask = SYSRQ_ENABLE_DUMP,
|
|
};
|
|
|
|
static void sysrq_handle_showstate(int key, struct tty_struct *tty)
|
|
{
|
|
show_state();
|
|
}
|
|
static struct sysrq_key_op sysrq_showstate_op = {
|
|
.handler = sysrq_handle_showstate,
|
|
.help_msg = "showTasks",
|
|
.action_msg = "Show State",
|
|
.enable_mask = SYSRQ_ENABLE_DUMP,
|
|
};
|
|
|
|
static void sysrq_handle_showstate_blocked(int key, struct tty_struct *tty)
|
|
{
|
|
show_state_filter(TASK_UNINTERRUPTIBLE);
|
|
}
|
|
static struct sysrq_key_op sysrq_showstate_blocked_op = {
|
|
.handler = sysrq_handle_showstate_blocked,
|
|
.help_msg = "shoW-blocked-tasks",
|
|
.action_msg = "Show Blocked State",
|
|
.enable_mask = SYSRQ_ENABLE_DUMP,
|
|
};
|
|
|
|
|
|
static void sysrq_handle_showmem(int key, struct tty_struct *tty)
|
|
{
|
|
show_mem();
|
|
}
|
|
static struct sysrq_key_op sysrq_showmem_op = {
|
|
.handler = sysrq_handle_showmem,
|
|
.help_msg = "showMem",
|
|
.action_msg = "Show Memory",
|
|
.enable_mask = SYSRQ_ENABLE_DUMP,
|
|
};
|
|
|
|
/*
|
|
* Signal sysrq helper function. Sends a signal to all user processes.
|
|
*/
|
|
static void send_sig_all(int sig)
|
|
{
|
|
struct task_struct *p;
|
|
|
|
for_each_process(p) {
|
|
if (p->mm && !is_global_init(p))
|
|
/* Not swapper, init nor kernel thread */
|
|
force_sig(sig, p);
|
|
}
|
|
}
|
|
|
|
static void sysrq_handle_term(int key, struct tty_struct *tty)
|
|
{
|
|
send_sig_all(SIGTERM);
|
|
console_loglevel = 8;
|
|
}
|
|
static struct sysrq_key_op sysrq_term_op = {
|
|
.handler = sysrq_handle_term,
|
|
.help_msg = "tErm",
|
|
.action_msg = "Terminate All Tasks",
|
|
.enable_mask = SYSRQ_ENABLE_SIGNAL,
|
|
};
|
|
|
|
static void moom_callback(struct work_struct *ignored)
|
|
{
|
|
out_of_memory(&NODE_DATA(0)->node_zonelists[ZONE_NORMAL],
|
|
GFP_KERNEL, 0);
|
|
}
|
|
|
|
static DECLARE_WORK(moom_work, moom_callback);
|
|
|
|
static void sysrq_handle_moom(int key, struct tty_struct *tty)
|
|
{
|
|
schedule_work(&moom_work);
|
|
}
|
|
static struct sysrq_key_op sysrq_moom_op = {
|
|
.handler = sysrq_handle_moom,
|
|
.help_msg = "Full",
|
|
.action_msg = "Manual OOM execution",
|
|
};
|
|
|
|
static void sysrq_handle_kill(int key, struct tty_struct *tty)
|
|
{
|
|
send_sig_all(SIGKILL);
|
|
console_loglevel = 8;
|
|
}
|
|
static struct sysrq_key_op sysrq_kill_op = {
|
|
.handler = sysrq_handle_kill,
|
|
.help_msg = "kIll",
|
|
.action_msg = "Kill All Tasks",
|
|
.enable_mask = SYSRQ_ENABLE_SIGNAL,
|
|
};
|
|
|
|
static void sysrq_handle_unrt(int key, struct tty_struct *tty)
|
|
{
|
|
normalize_rt_tasks();
|
|
}
|
|
static struct sysrq_key_op sysrq_unrt_op = {
|
|
.handler = sysrq_handle_unrt,
|
|
.help_msg = "Nice",
|
|
.action_msg = "Nice All RT Tasks",
|
|
.enable_mask = SYSRQ_ENABLE_RTNICE,
|
|
};
|
|
|
|
/* Key Operations table and lock */
|
|
static DEFINE_SPINLOCK(sysrq_key_table_lock);
|
|
|
|
static struct sysrq_key_op *sysrq_key_table[36] = {
|
|
&sysrq_loglevel_op, /* 0 */
|
|
&sysrq_loglevel_op, /* 1 */
|
|
&sysrq_loglevel_op, /* 2 */
|
|
&sysrq_loglevel_op, /* 3 */
|
|
&sysrq_loglevel_op, /* 4 */
|
|
&sysrq_loglevel_op, /* 5 */
|
|
&sysrq_loglevel_op, /* 6 */
|
|
&sysrq_loglevel_op, /* 7 */
|
|
&sysrq_loglevel_op, /* 8 */
|
|
&sysrq_loglevel_op, /* 9 */
|
|
|
|
/*
|
|
* a: Don't use for system provided sysrqs, it is handled specially on
|
|
* sparc and will never arrive.
|
|
*/
|
|
NULL, /* a */
|
|
&sysrq_reboot_op, /* b */
|
|
&sysrq_crashdump_op, /* c & ibm_emac driver debug */
|
|
&sysrq_showlocks_op, /* d */
|
|
&sysrq_term_op, /* e */
|
|
&sysrq_moom_op, /* f */
|
|
/* g: May be registered by ppc for kgdb */
|
|
NULL, /* g */
|
|
NULL, /* h */
|
|
&sysrq_kill_op, /* i */
|
|
NULL, /* j */
|
|
&sysrq_SAK_op, /* k */
|
|
NULL, /* l */
|
|
&sysrq_showmem_op, /* m */
|
|
&sysrq_unrt_op, /* n */
|
|
/* o: This will often be registered as 'Off' at init time */
|
|
NULL, /* o */
|
|
&sysrq_showregs_op, /* p */
|
|
&sysrq_show_timers_op, /* q */
|
|
&sysrq_unraw_op, /* r */
|
|
&sysrq_sync_op, /* s */
|
|
&sysrq_showstate_op, /* t */
|
|
&sysrq_mountro_op, /* u */
|
|
/* v: May be registered at init time by SMP VOYAGER */
|
|
NULL, /* v */
|
|
&sysrq_showstate_blocked_op, /* w */
|
|
/* x: May be registered on ppc/powerpc for xmon */
|
|
NULL, /* x */
|
|
NULL, /* y */
|
|
NULL /* z */
|
|
};
|
|
|
|
/* key2index calculation, -1 on invalid index */
|
|
static int sysrq_key_table_key2index(int key)
|
|
{
|
|
int retval;
|
|
|
|
if ((key >= '0') && (key <= '9'))
|
|
retval = key - '0';
|
|
else if ((key >= 'a') && (key <= 'z'))
|
|
retval = key + 10 - 'a';
|
|
else
|
|
retval = -1;
|
|
return retval;
|
|
}
|
|
|
|
/*
|
|
* get and put functions for the table, exposed to modules.
|
|
*/
|
|
struct sysrq_key_op *__sysrq_get_key_op(int key)
|
|
{
|
|
struct sysrq_key_op *op_p = NULL;
|
|
int i;
|
|
|
|
i = sysrq_key_table_key2index(key);
|
|
if (i != -1)
|
|
op_p = sysrq_key_table[i];
|
|
return op_p;
|
|
}
|
|
|
|
static void __sysrq_put_key_op(int key, struct sysrq_key_op *op_p)
|
|
{
|
|
int i = sysrq_key_table_key2index(key);
|
|
|
|
if (i != -1)
|
|
sysrq_key_table[i] = op_p;
|
|
}
|
|
|
|
/*
|
|
* This is the non-locking version of handle_sysrq. It must/can only be called
|
|
* by sysrq key handlers, as they are inside of the lock
|
|
*/
|
|
void __handle_sysrq(int key, struct tty_struct *tty, int check_mask)
|
|
{
|
|
struct sysrq_key_op *op_p;
|
|
int orig_log_level;
|
|
int i;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&sysrq_key_table_lock, flags);
|
|
orig_log_level = console_loglevel;
|
|
console_loglevel = 7;
|
|
printk(KERN_INFO "SysRq : ");
|
|
|
|
op_p = __sysrq_get_key_op(key);
|
|
if (op_p) {
|
|
/*
|
|
* Should we check for enabled operations (/proc/sysrq-trigger
|
|
* should not) and is the invoked operation enabled?
|
|
*/
|
|
if (!check_mask || sysrq_on_mask(op_p->enable_mask)) {
|
|
printk("%s\n", op_p->action_msg);
|
|
console_loglevel = orig_log_level;
|
|
op_p->handler(key, tty);
|
|
} else {
|
|
printk("This sysrq operation is disabled.\n");
|
|
}
|
|
} else {
|
|
printk("HELP : ");
|
|
/* Only print the help msg once per handler */
|
|
for (i = 0; i < ARRAY_SIZE(sysrq_key_table); i++) {
|
|
if (sysrq_key_table[i]) {
|
|
int j;
|
|
|
|
for (j = 0; sysrq_key_table[i] !=
|
|
sysrq_key_table[j]; j++)
|
|
;
|
|
if (j != i)
|
|
continue;
|
|
printk("%s ", sysrq_key_table[i]->help_msg);
|
|
}
|
|
}
|
|
printk("\n");
|
|
console_loglevel = orig_log_level;
|
|
}
|
|
spin_unlock_irqrestore(&sysrq_key_table_lock, flags);
|
|
}
|
|
|
|
/*
|
|
* This function is called by the keyboard handler when SysRq is pressed
|
|
* and any other keycode arrives.
|
|
*/
|
|
void handle_sysrq(int key, struct tty_struct *tty)
|
|
{
|
|
if (sysrq_on())
|
|
__handle_sysrq(key, tty, 1);
|
|
}
|
|
EXPORT_SYMBOL(handle_sysrq);
|
|
|
|
static int __sysrq_swap_key_ops(int key, struct sysrq_key_op *insert_op_p,
|
|
struct sysrq_key_op *remove_op_p)
|
|
{
|
|
|
|
int retval;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&sysrq_key_table_lock, flags);
|
|
if (__sysrq_get_key_op(key) == remove_op_p) {
|
|
__sysrq_put_key_op(key, insert_op_p);
|
|
retval = 0;
|
|
} else {
|
|
retval = -1;
|
|
}
|
|
spin_unlock_irqrestore(&sysrq_key_table_lock, flags);
|
|
return retval;
|
|
}
|
|
|
|
int register_sysrq_key(int key, struct sysrq_key_op *op_p)
|
|
{
|
|
return __sysrq_swap_key_ops(key, op_p, NULL);
|
|
}
|
|
EXPORT_SYMBOL(register_sysrq_key);
|
|
|
|
int unregister_sysrq_key(int key, struct sysrq_key_op *op_p)
|
|
{
|
|
return __sysrq_swap_key_ops(key, NULL, op_p);
|
|
}
|
|
EXPORT_SYMBOL(unregister_sysrq_key);
|