From a4afee02a5dd4f20c08fca26e9b610e72d0bcbf0 Mon Sep 17 00:00:00 2001
From: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Date: Fri, 14 Jul 2006 00:24:18 -0700
Subject: [PATCH] [PATCH] Fix sighand->siglock usage in kernel/acct.c

IRQs must be disabled before taking ->siglock.

Noticed by lockdep.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
 kernel/acct.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/acct.c b/kernel/acct.c
index f18e0b8df3e1..2a7c933651c7 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -488,7 +488,7 @@ static void do_acct_process(struct file *file)
 		old_encode_dev(tty_devnum(current->signal->tty)) : 0;
 	read_unlock(&tasklist_lock);
 
-	spin_lock(&current->sighand->siglock);
+	spin_lock_irq(&current->sighand->siglock);
 	ac.ac_utime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_utime)));
 	ac.ac_stime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_stime)));
 	ac.ac_flag = pacct->ac_flag;
@@ -496,7 +496,7 @@ static void do_acct_process(struct file *file)
 	ac.ac_minflt = encode_comp_t(pacct->ac_minflt);
 	ac.ac_majflt = encode_comp_t(pacct->ac_majflt);
 	ac.ac_exitcode = pacct->ac_exitcode;
-	spin_unlock(&current->sighand->siglock);
+	spin_unlock_irq(&current->sighand->siglock);
 	ac.ac_io = encode_comp_t(0 /* current->io_usage */);	/* %% */
 	ac.ac_rw = encode_comp_t(ac.ac_io / 1024);
 	ac.ac_swaps = encode_comp_t(0);