@@ -1195,7 +1195,7 @@ old_sess_out:
static int __iscsi_target_login_thread(struct iscsi_np *np)
{
u8 *buffer, zero_tsih = 0;
- int ret = 0, rc, stop;
+ int ret = 0, rc;
struct iscsi_conn *conn = NULL;
struct iscsi_login *login;
struct iscsi_portal_group *tpg = NULL;
@@ -1209,6 +1209,9 @@ static int __iscsi_target_login_thread(struct iscsi_np *np)
if (np->np_thread_state == ISCSI_NP_THREAD_RESET) {
np->np_thread_state = ISCSI_NP_THREAD_ACTIVE;
complete(&np->np_restart_comp);
+ } else if (np->np_thread_state == ISCSI_NP_THREAD_SHUTDOWN) {
+ spin_unlock_bh(&np->np_thread_lock);
+ goto exit;
} else {
np->np_thread_state = ISCSI_NP_THREAD_ACTIVE;
}
@@ -1401,10 +1404,8 @@ old_sess_out:
}
out:
- stop = kthread_should_stop();
- /* Wait for another socket.. */
- if (!stop)
- return 1;
+ return 1;
+
exit:
iscsi_stop_login_thread_timer(np);
spin_lock_bh(&np->np_thread_lock);
@@ -1421,7 +1422,7 @@ int iscsi_target_login_thread(void *arg)
allow_signal(SIGINT);
- while (!kthread_should_stop()) {
+ while (1) {
ret = __iscsi_target_login_thread(np);
/*
* We break and exit here unless another sock_accept() call
This is a note to let you know that I have just added a patch titled iscsi-target: fix iscsit_del_np deadlock on unload to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue This patch is scheduled to be released in version 3.13.11.5. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.13.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From c248e417d668aaa32d78623ede63598e791239a8 Mon Sep 17 00:00:00 2001 From: Mikulas Patocka <mpatocka@redhat.com> Date: Mon, 23 Jun 2014 13:42:37 -0400 Subject: iscsi-target: fix iscsit_del_np deadlock on unload commit 81a9c5e72bdf7109a65102ca61d8cbd722cf4021 upstream. On uniprocessor preemptible kernel, target core deadlocks on unload. The following events happen: * iscsit_del_np is called * it calls send_sig(SIGINT, np->np_thread, 1); * the scheduler switches to the np_thread * the np_thread is woken up, it sees that kthread_should_stop() returns false, so it doesn't terminate * the np_thread clears signals with flush_signals(current); and goes back to sleep in iscsit_accept_np * the scheduler switches back to iscsit_del_np * iscsit_del_np calls kthread_stop(np->np_thread); * the np_thread is waiting in iscsit_accept_np and it doesn't respond to kthread_stop The deadlock could be resolved if the administrator sends SIGINT signal to the np_thread with killall -INT iscsi_np The reproducible deadlock was introduced in commit db6077fd0b7dd41dc6ff18329cec979379071f87, but the thread-stopping code was racy even before. This patch fixes the problem. Using kthread_should_stop to stop the np_thread is unreliable, so we test np_thread_state instead. If np_thread_state equals ISCSI_NP_THREAD_SHUTDOWN, the thread exits. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/target/iscsi/iscsi_target_login.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) -- 1.9.1