sysrq, intel_fb: fix sysrq g collision

Commit 79e53945 introduced a
regression where you cannot use sysrq 'g' to enter kgdb.  The solution
is to move the intel fb sysrq over to V for video instead of G for
graphics.  The SMP VOYAGER code to register for the sysrq-v is not
anywhere to be found in the mainline kernel, so the comments in the
code were cleaned up as well.

This patch also cleans up the sysrq definitions for kgdb to make it
generic for the kernel debugger, such that the sysrq 'g' can be used
in the future to enter a gdbstub or another kernel debugger.
Signed-off-by: NJason Wessel <jason.wessel@windriver.com>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>

drivers/char/sysrq.c

@@ -406,7 +406,7 @@ static struct sysrq_key_op *sysrq_key_table[36] = {
 	&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 - reserved for help */
 	&sysrq_kill_op,			/* i */
@@ -431,7 +431,7 @@ 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 */

drivers/gpu/drm/i915/intel_fb.c

@@ -864,7 +864,7 @@ static void intelfb_sysrq(int dummy1, struct tty_struct *dummy3)
 
 static struct sysrq_key_op sysrq_intelfb_restore_op = {
         .handler = intelfb_sysrq,
-        .help_msg = "force-fb(G)",
+        .help_msg = "force-fb(V)",
         .action_msg = "Restore framebuffer console",
 };
 
@@ -898,7 +898,7 @@ int intelfb_probe(struct drm_device *dev)
 		ret = intelfb_single_fb_probe(dev);
 	}
 
-	register_sysrq_key('g', &sysrq_intelfb_restore_op);
+	register_sysrq_key('v', &sysrq_intelfb_restore_op);
 
 	return ret;
 }

kernel/kgdb.c

@@ -1583,8 +1583,8 @@ static void sysrq_handle_gdb(int key, struct tty_struct *tty)
 
 static struct sysrq_key_op sysrq_gdb_op = {
 	.handler	= sysrq_handle_gdb,
-	.help_msg	= "Gdb",
-	.action_msg	= "GDB",
+	.help_msg	= "debug(G)",
+	.action_msg	= "DEBUG",
 };
 #endif