do_coredump: Do not take BKL

core_pattern is not actually protected and hasn't been
ever since we introduced procfs support for sysctl -- a
_long_ time. Don't take it here either.

Also nothing inside do_coredump appears to require bkl
protection.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[ remove smp_lock.h headers ]
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>

fs/exec.c

@@ -28,7 +28,6 @@
 #include <linux/mm.h>
 #include <linux/stat.h>
 #include <linux/fcntl.h>
-#include <linux/smp_lock.h>
 #include <linux/swap.h>
 #include <linux/string.h>
 #include <linux/init.h>
@@ -1891,13 +1890,7 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs)
 	 */
 	clear_thread_flag(TIF_SIGPENDING);
 
-	/*
-	 * lock_kernel() because format_corename() is controlled by sysctl, which
-	 * uses lock_kernel()
-	 */
- 	lock_kernel();
 	ispipe = format_corename(corename, signr);
-	unlock_kernel();
 
  	if (ispipe) {
 		int dump_count;