diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 17a0190bd88f..4452f8553301 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -306,6 +306,14 @@ static bool nvme_dbbuf_update_and_check_event(u16 value, 
u32 *dbbuf_db,
                old_value = *dbbuf_db;
                *dbbuf_db = value;
+ /*
+                * Ensure that the doorbell is updated before reading
+                * the EventIdx from memory. NVMe controller should have
+                * similar ordering guarantees - update EventIdx before
+                * reading doorbell.
+                */
+               mb();
+
                if (!nvme_dbbuf_need_event(*dbbuf_ei, value, old_value))
                        return false;
        }

Reviewed-by: Sagi Grimberg <s...@grimberg.me>

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