dmaengine: idxd: fix array index when int_handles are being used

[ Upstream commit da435ae ]

The index to the irq vector should be local and has no relation to
the assigned interrupt handle. Assign the MSIX interrupt index that is
programmed for the descriptor. The interrupt handle only matters when it
comes to hardware descriptor programming.

Fixes: eb15e71 ("dmaengine: idxd: add interrupt handle request and release support")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162456176939.1121476.3366256009925001897.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/dma/idxd/submit.c

@@ -128,19 +128,8 @@ int idxd_submit_desc(struct idxd_wq *wq, struct idxd_desc *desc)
 	 * Pending the descriptor to the lockless list for the irq_entry
 	 * that we designated the descriptor to.
 	 */
-	if (desc->hw->flags & IDXD_OP_FLAG_RCI) {
-		int vec;
-
-		/*
-		 * If the driver is on host kernel, it would be the value
-		 * assigned to interrupt handle, which is index for MSIX
-		 * vector. If it's guest then can't use the int_handle since
-		 * that is the index to IMS for the entire device. The guest
-		 * device local index will be used.
-		 */
-		vec = !idxd->int_handles ? desc->hw->int_handle : desc->vector;
-		llist_add(&desc->llnode, &idxd->irq_entries[vec].pending_llist);
-	}
+	if (desc->hw->flags & IDXD_OP_FLAG_RCI)
+		llist_add(&desc->llnode, &idxd->irq_entries[desc->vector].pending_llist);
 
 	return 0;
 }