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Diffstat (limited to 'drivers/hv/channel.c')
-rw-r--r--drivers/hv/channel.c27
1 files changed, 13 insertions, 14 deletions
diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index 81a80c82f1bd..321b8833fa6f 100644
--- a/drivers/hv/channel.c
+++ b/drivers/hv/channel.c
@@ -502,12 +502,15 @@ int vmbus_teardown_gpadl(struct vmbus_channel *channel, u32 gpadl_handle)
502 502
503 wait_for_completion(&info->waitevent); 503 wait_for_completion(&info->waitevent);
504 504
505 if (channel->rescind) {
506 ret = -ENODEV;
507 goto post_msg_err;
508 }
509
510post_msg_err: 505post_msg_err:
506 /*
507 * If the channel has been rescinded;
508 * we will be awakened by the rescind
509 * handler; set the error code to zero so we don't leak memory.
510 */
511 if (channel->rescind)
512 ret = 0;
513
511 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); 514 spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags);
512 list_del(&info->msglistentry); 515 list_del(&info->msglistentry);
513 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); 516 spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags);
@@ -530,20 +533,18 @@ static int vmbus_close_internal(struct vmbus_channel *channel)
530 int ret; 533 int ret;
531 534
532 /* 535 /*
533 * vmbus_on_event(), running in the tasklet, can race 536 * vmbus_on_event(), running in the per-channel tasklet, can race
534 * with vmbus_close_internal() in the case of SMP guest, e.g., when 537 * with vmbus_close_internal() in the case of SMP guest, e.g., when
535 * the former is accessing channel->inbound.ring_buffer, the latter 538 * the former is accessing channel->inbound.ring_buffer, the latter
536 * could be freeing the ring_buffer pages. 539 * could be freeing the ring_buffer pages, so here we must stop it
537 * 540 * first.
538 * To resolve the race, we can serialize them by disabling the
539 * tasklet when the latter is running here.
540 */ 541 */
541 hv_event_tasklet_disable(channel); 542 tasklet_disable(&channel->callback_event);
542 543
543 /* 544 /*
544 * In case a device driver's probe() fails (e.g., 545 * In case a device driver's probe() fails (e.g.,
545 * util_probe() -> vmbus_open() returns -ENOMEM) and the device is 546 * util_probe() -> vmbus_open() returns -ENOMEM) and the device is
546 * rescinded later (e.g., we dynamically disble an Integrated Service 547 * rescinded later (e.g., we dynamically disable an Integrated Service
547 * in Hyper-V Manager), the driver's remove() invokes vmbus_close(): 548 * in Hyper-V Manager), the driver's remove() invokes vmbus_close():
548 * here we should skip most of the below cleanup work. 549 * here we should skip most of the below cleanup work.
549 */ 550 */
@@ -605,8 +606,6 @@ static int vmbus_close_internal(struct vmbus_channel *channel)
605 get_order(channel->ringbuffer_pagecount * PAGE_SIZE)); 606 get_order(channel->ringbuffer_pagecount * PAGE_SIZE));
606 607
607out: 608out:
608 hv_event_tasklet_enable(channel);
609
610 return ret; 609 return ret;
611} 610}
612 611