This changes do_io_accounting to use the new exec_update_mutex instead of cred_guard_mutex.

This fixes possible deadlocks when the trace is accessing /proc/$pid/io for instance.

This should be safe, as the credentials are only used for reading.

Signed-off-by: Bernd Edlinger bernd.edlinger@hotmail.de --- fs/proc/base.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/proc/base.c b/fs/proc/base.c index fed76abf..6b13fc4 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -2861,7 +2861,7 @@ static int do_io_accounting(struct task_struct *task, struct seq_file *m, int wh unsigned long flags; int result;

- result = mutex_lock_killable(&task->signal->cred_guard_mutex); + result = mutex_lock_killable(&task->signal->exec_update_mutex); if (result) return result;

@@ -2897,7 +2897,7 @@ static int do_io_accounting(struct task_struct *task, struct seq_file *m, int wh result = 0;

out_unlock: - mutex_unlock(&task->signal->cred_guard_mutex); + mutex_unlock(&task->signal->exec_update_mutex); return result; }