X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=drivers%2Fchar%2Fsysrq.c;h=50eecfe1d72449fb8d5e8f4604e09dc88bd756b7;hb=a017421ddcdf34474f1133b27e33ab2ca6c19b96;hp=5a3eab0882a024f3fab11a2b01d63b3a10ef9b6c;hpb=506c10f26c481b7f8ef27c1c79290f68989b2e9e;p=safe%2Fjmp%2Flinux-2.6

diff --git a/drivers/char/sysrq.c b/drivers/char/sysrq.c
index 5a3eab0..50eecfe 100644
--- a/drivers/char/sysrq.c
+++ b/drivers/char/sysrq.c
@@ -24,6 +24,7 @@
 #include <linux/sysrq.h>
 #include <linux/kbd_kern.h>
 #include <linux/proc_fs.h>
+#include <linux/nmi.h>
 #include <linux/quotaops.h>
 #include <linux/perf_counter.h>
 #include <linux/kernel.h>
@@ -35,8 +36,6 @@
 #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>
 
@@ -122,20 +121,20 @@ static struct sysrq_key_op sysrq_unraw_op = {
 #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)
+static void sysrq_handle_crash(int key, struct tty_struct *tty)
 {
-	crash_kexec(get_irq_regs());
+	char *killer = NULL;
+
+	panic_on_oops = 1;	/* force panic */
+	wmb();
+	*killer = 1;
 }
-static struct sysrq_key_op sysrq_crashdump_op = {
-	.handler	= sysrq_handle_crashdump,
-	.help_msg	= "Crashdump",
-	.action_msg	= "Trigger a crashdump",
+static struct sysrq_key_op sysrq_crash_op = {
+	.handler	= sysrq_handle_crash,
+	.help_msg	= "Crash",
+	.action_msg	= "Trigger a crash",
 	.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)
 {
@@ -224,12 +223,20 @@ static DECLARE_WORK(sysrq_showallcpus, sysrq_showregs_othercpus);
 
 static void sysrq_handle_showallcpus(int key, struct tty_struct *tty)
 {
-	struct pt_regs *regs = get_irq_regs();
-	if (regs) {
-		printk(KERN_INFO "CPU%d:\n", smp_processor_id());
-		show_regs(regs);
+	/*
+	 * Fall back to the workqueue based printing if the
+	 * backtrace printing did not succeed or the
+	 * architecture has no support for it:
+	 */
+	if (!trigger_all_cpu_backtrace()) {
+		struct pt_regs *regs = get_irq_regs();
+
+		if (regs) {
+			printk(KERN_INFO "CPU%d:\n", smp_processor_id());
+			show_regs(regs);
+		}
+		schedule_work(&sysrq_showallcpus);
 	}
-	schedule_work(&sysrq_showallcpus);
 }
 
 static struct sysrq_key_op sysrq_showallcpus_op = {
@@ -285,7 +292,7 @@ static void sysrq_ftrace_dump(int key, struct tty_struct *tty)
 }
 static struct sysrq_key_op sysrq_ftrace_dump_op = {
 	.handler	= sysrq_ftrace_dump,
-	.help_msg	= "dumpZ-ftrace-buffer",
+	.help_msg	= "dump-ftrace-buffer(Z)",
 	.action_msg	= "Dump ftrace buffer",
 	.enable_mask	= SYSRQ_ENABLE_DUMP,
 };
@@ -348,6 +355,19 @@ static struct sysrq_key_op sysrq_moom_op = {
 	.enable_mask	= SYSRQ_ENABLE_SIGNAL,
 };
 
+#ifdef CONFIG_BLOCK
+static void sysrq_handle_thaw(int key, struct tty_struct *tty)
+{
+	emergency_thaw_all();
+}
+static struct sysrq_key_op sysrq_thaw_op = {
+	.handler	= sysrq_handle_thaw,
+	.help_msg	= "thaw-filesystems(J)",
+	.action_msg	= "Emergency Thaw of all frozen filesystems",
+	.enable_mask	= SYSRQ_ENABLE_SIGNAL,
+};
+#endif
+
 static void sysrq_handle_kill(int key, struct tty_struct *tty)
 {
 	send_sig_all(SIGKILL);
@@ -392,15 +412,19 @@ static struct sysrq_key_op *sysrq_key_table[36] = {
 	 */
 	NULL,				/* a */
 	&sysrq_reboot_op,		/* b */
-	&sysrq_crashdump_op,		/* c & ibm_emac driver debug */
+	&sysrq_crash_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 */
+	/* g: May be registered for the kernel debugger */
 	NULL,				/* g */
-	NULL,				/* h */
+	NULL,				/* h - reserved for help */
 	&sysrq_kill_op,			/* i */
+#ifdef CONFIG_BLOCK
+	&sysrq_thaw_op,			/* j */
+#else
 	NULL,				/* j */
+#endif
 	&sysrq_SAK_op,			/* k */
 #ifdef CONFIG_SMP
 	&sysrq_showallcpus_op,		/* l */
@@ -417,7 +441,7 @@ static struct sysrq_key_op *sysrq_key_table[36] = {
 	&sysrq_sync_op,			/* s */
 	&sysrq_showstate_op,		/* t */
 	&sysrq_mountro_op,		/* u */
-	/* v: May be registered at init time by SMP VOYAGER */
+	/* v: May be registered for frame buffer console restore */
 	NULL,				/* v */
 	&sysrq_showstate_blocked_op,	/* w */
 	/* x: May be registered on ppc/powerpc for xmon */
@@ -475,6 +499,12 @@ void __handle_sysrq(int key, struct tty_struct *tty, int check_mask)
 	unsigned long flags;
 
 	spin_lock_irqsave(&sysrq_key_table_lock, flags);
+	/*
+	 * Raise the apparent loglevel to maximum so that the sysrq header
+	 * is shown to provide the user with positive feedback.  We do not
+	 * simply emit this at KERN_EMERG as that would change message
+	 * routing in the consumers of /proc/kmsg.
+	 */
 	orig_log_level = console_loglevel;
 	console_loglevel = 7;
 	printk(KERN_INFO "SysRq : ");