From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from zimbra13.linbit.com (zimbra.linbit.com [212.69.161.123]) by mail09.linbit.com (LINBIT Mail Daemon) with ESMTP id 6F3C5101E04C for ; Wed, 9 Jul 2014 21:18:33 +0200 (CEST) From: Philipp Reisner To: linux-kernel@vger.kernel.org, Jens Axboe Date: Wed, 9 Jul 2014 21:18:32 +0200 Message-Id: <1404933512-5166-2-git-send-email-philipp.reisner@linbit.com> In-Reply-To: <1404933512-5166-1-git-send-email-philipp.reisner@linbit.com> References: <1404933512-5166-1-git-send-email-philipp.reisner@linbit.com> Cc: drbd-dev@lists.linbit.com Subject: [Drbd-dev] [PATCH] drbd: fix regression 'out of mem, failed to invoke fence-peer helper' List-Id: "*Coordination* of development, patches, contributions -- *Questions* \(even to developers\) go to drbd-user, please." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Lars Ellenberg Since linux kernel 3.13, kthread_run() internally uses wait_for_completion_killable(). We sometimes may use kthread_run() while we still have a signal pending, which we used to kick our threads out of potentially blocking network functions, causing kthread_run() to mistake that as a new fatal signal and fail. Fix: flush_signals() before kthread_run(). Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg --- drivers/block/drbd/drbd_nl.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c index 1b35c45..3f2e167 100644 --- a/drivers/block/drbd/drbd_nl.c +++ b/drivers/block/drbd/drbd_nl.c @@ -544,6 +544,12 @@ void conn_try_outdate_peer_async(struct drbd_connection *connection) struct task_struct *opa; kref_get(&connection->kref); + /* We may just have force_sig()'ed this thread + * to get it out of some blocking network function. + * Clear signals; otherwise kthread_run(), which internally uses + * wait_on_completion_killable(), will mistake our pending signal + * for a new fatal signal and fail. */ + flush_signals(current); opa = kthread_run(_try_outdate_peer_async, connection, "drbd_async_h"); if (IS_ERR(opa)) { drbd_err(connection, "out of mem, failed to invoke fence-peer helper\n"); -- 1.9.1