1 files changed, 44 insertions, 5 deletions

diff --git a/drivers/firewire/core-iso.c b/drivers/firewire/core-iso.c
index b3eda38a36f3..a67493862c85 100644
--- a/drivers/firewire/core-iso.c
+++ b/drivers/firewire/core-iso.c
@@ -209,23 +209,63 @@ void fw_iso_context_queue_flush(struct fw_iso_context *ctx)
 }
 EXPORT_SYMBOL(fw_iso_context_queue_flush);
 
+/**
+ * fw_iso_context_flush_completions() - process isochronous context in current process context.
+ * @ctx: the isochronous context
+ *
+ * Process the isochronous context in the current process context. The registered callback function
+ * is called when a queued packet buffer with the interrupt flag is completed, either after
+ * transmission in the IT context or after being filled in the IR context. Additionally, the
+ * callback function is also called for the packet buffer completed at last. Furthermore, the
+ * callback function is called as well when the header buffer in the context becomes full. If it is
+ * required to process the context asynchronously, fw_iso_context_schedule_flush_completions() is
+ * available instead.
+ *
+ * Context: Process context. May sleep due to disable_work_sync().
+ */
 int fw_iso_context_flush_completions(struct fw_iso_context *ctx)
 {
+	int err;
+
 	trace_isoc_outbound_flush_completions(ctx);
 	trace_isoc_inbound_single_flush_completions(ctx);
 	trace_isoc_inbound_multiple_flush_completions(ctx);
 
-	return ctx->card->driver->flush_iso_completions(ctx);
+	might_sleep();
+
+	// Avoid dead lock due to programming mistake.
+	if (WARN_ON_ONCE(current_work() == &ctx->work))
+		return 0;
+
+	disable_work_sync(&ctx->work);
+
+	err = ctx->card->driver->flush_iso_completions(ctx);
+
+	enable_work(&ctx->work);
+
+	return err;
 }
 EXPORT_SYMBOL(fw_iso_context_flush_completions);
 
 int fw_iso_context_stop(struct fw_iso_context *ctx)
 {
+	int err;
+
 	trace_isoc_outbound_stop(ctx);
 	trace_isoc_inbound_single_stop(ctx);
 	trace_isoc_inbound_multiple_stop(ctx);
 
-	return ctx->card->driver->stop_iso(ctx);
+	might_sleep();
+
+	// Avoid dead lock due to programming mistake.
+	if (WARN_ON_ONCE(current_work() == &ctx->work))
+		return 0;
+
+	err = ctx->card->driver->stop_iso(ctx);
+
+	cancel_work_sync(&ctx->work);
+
+	return err;
 }
 EXPORT_SYMBOL(fw_iso_context_stop);
 
@@ -375,9 +415,8 @@ void fw_iso_resource_manage(struct fw_card *card, int generation,
 	u32 channels_lo = channels_mask >> 32;	/* channels 63...32 */
 	int irm_id, ret, c = -EINVAL;
 
-	spin_lock_irq(&card->lock);
-	irm_id = card->irm_node->node_id;
-	spin_unlock_irq(&card->lock);
+	scoped_guard(spinlock_irq, &card->lock)
+		irm_id = card->irm_node->node_id;
 
 	if (channels_hi)
 		c = manage_channel(card, irm_id, generation, channels_hi,