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 <[email protected]>
