[PATCH 4.15 012/163] RDMA/rxe: Fix rxe_qp_cleanup()

Greg Kroah-Hartman
2018-02-21T12:47:21Z

From: Bart Van Assche <bart.vanassche@wdc.com>

commit bb3ffb7ad48a21e98a5c64eb21103a74fd9f03f6 upstream.

rxe_qp_cleanup() can sleep so it must be run in thread context and
not in atomic context. This patch avoids that the following bug is
triggered:

Kernel BUG at 00000000560033f3 [verbose debug info unavailable]
BUG: sleeping function called from invalid context at net/core/sock.c:2761
in_atomic(): 1, irqs_disabled(): 0, pid: 7, name: ksoftirqd/0
INFO: lockdep is turned off.
Preemption disabled at:
[<00000000b6e69628>] __do_softirq+0x4e/0x540
CPU: 0 PID: 7 Comm: ksoftirqd/0 Not tainted 4.15.0-rc7-dbg+ #4
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014
Call Trace:
dump_stack+0x85/0xbf
___might_sleep+0x177/0x260
lock_sock_nested+0x1d/0x90
inet_shutdown+0x2e/0xd0
rxe_qp_cleanup+0x107/0x140 [rdma_rxe]
rxe_elem_release+0x18/0x80 [rdma_rxe]
rxe_requester+0x1cf/0x11b0 [rdma_rxe]
rxe_do_task+0x78/0xf0 [rdma_rxe]
tasklet_action+0x99/0x270
__do_softirq+0xc0/0x540
run_ksoftirqd+0x1c/0x70
smpboot_thread_fn+0x1be/0x270
kthread+0x117/0x130
ret_from_fork+0x24/0x30

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Moni Shoua <monis@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/infiniband/sw/rxe/rxe_qp.c | 12 ++++++++++--
drivers/infiniband/sw/rxe/rxe_verbs.h | 3 +++
2 files changed, 13 insertions(+), 2 deletions(-)

--- a/drivers/infiniband/sw/rxe/rxe_qp.c
+++ b/drivers/infiniband/sw/rxe/rxe_qp.c
@@ -824,9 +824,9 @@ void rxe_qp_destroy(struct rxe_qp *qp)
}

/* called when the last reference to the qp is dropped */
-void rxe_qp_cleanup(struct rxe_pool_entry *arg)
+static void rxe_qp_do_cleanup(struct work_struct *work)
{
- struct rxe_qp *qp = container_of(arg, typeof(*qp), pelem);
+ struct rxe_qp *qp = container_of(work, typeof(*qp), cleanup_work.work);

rxe_drop_all_mcast_groups(qp);

@@ -859,3 +859,11 @@ void rxe_qp_cleanup(struct rxe_pool_entr
kernel_sock_shutdown(qp->sk, SHUT_RDWR);
sock_release(qp->sk);
}
+
+/* called when the last reference to the qp is dropped */
+void rxe_qp_cleanup(struct rxe_pool_entry *arg)
+{
+ struct rxe_qp *qp = container_of(arg, typeof(*qp), pelem);
+
+ execute_in_process_context(rxe_qp_do_cleanup, &qp->cleanup_work);
+}
--- a/drivers/infiniband/sw/rxe/rxe_verbs.h
+++ b/drivers/infiniband/sw/rxe/rxe_verbs.h
@@ -35,6 +35,7 @@
#define RXE_VERBS_H

#include <linux/interrupt.h>
+#include <linux/workqueue.h>
#include <rdma/rdma_user_rxe.h>
#include "rxe_pool.h"
#include "rxe_task.h"
@@ -281,6 +282,8 @@ struct rxe_qp {
struct timer_list rnr_nak_timer;

spinlock_t state_lock; /* guard requester and completer */
+
+ struct execute_work cleanup_work;
};

enum rxe_mem_state {