printk,kdb: capture printk() when in kdb shell

Certain calls from the kdb shell will call out to printk(), and any of
these calls should get vectored back to the kdb_printf() so that the
kdb pager and processing can be used, as well as to properly channel
I/O to the polled I/O devices.

CC: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 64ef9ac14ba..b724c791b6d 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -1056,7 +1056,9 @@ static void kdb_dumpregs(struct pt_regs *regs)
 {
         int old_lvl = console_loglevel;
         console_loglevel = 15;
+        kdb_trap_printk++;
         show_regs(regs);
+        kdb_trap_printk--;
         kdb_printf("\n");
         console_loglevel = old_lvl;
 }
@@ -1819,7 +1821,9 @@ static int kdb_sr(int argc, const char **argv)
         if (argc != 1)
                 return KDB_ARGCOUNT;
         sysrq_toggle_support(1);
+        kdb_trap_printk++;
         handle_sysrq(*argv[1], NULL);
+        kdb_trap_printk--;
 
         return 0;
 }