From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mandeep Singh Baines Subject: [PATCH] exec: log when wait_for_dump_helpers aborts due to a signal Date: Tue, 25 Oct 2011 18:07:08 -0700 Message-ID: <1319591228-20397-1-git-send-email-msb@chromium.org> Cc: Mandeep Singh Baines , Alexander Viro , Neil Horman , Earl Chew , Oleg Nesterov , Andi Kleen , Alan Cox , Andrew Morton , linux-fsdevel@vger.kernel.org To: linux-kernel@vger.kernel.org Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org To allow coredump pipe readers to look at /proc/ of the crashing process, the kernel waits for the reader to exit. However, the wait is silently aborted if the crashing process is signalled. This patch, logs whenever wait_for_dump_helpers is aborted or in order to assist in debugging cases where /proc/ is gone. Alternatively, we may want to consider not aborting on a signal. You could always break the loop by killing the reader process. Reference: http://crosbug.com/21559 Signed-off-by: Mandeep Singh Baines Cc: Alexander Viro Cc: Neil Horman Cc: Earl Chew Cc: Oleg Nesterov Cc: Andi Kleen Cc: Alan Cox Cc: Andrew Morton Cc: linux-fsdevel@vger.kernel.org --- fs/exec.c | 9 ++++++++- 1 files changed, 8 insertions(+), 1 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index 25dcbe5..5d4190d 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -2030,7 +2030,14 @@ static void wait_for_dump_helpers(struct file *file) pipe->readers++; pipe->writers--; - while ((pipe->readers > 1) && (!signal_pending(current))) { + while (pipe->readers > 1) { + if (signal_pending(current)) { + pr_info("wait_for_dump_helpers[%d]: " + "aborted due to signal\n", + task_pid_nr(current)); + break; + } + wake_up_interruptible_sync(&pipe->wait); kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN); pipe_wait(pipe); -- 1.7.3.1