Messages in this thread | | | Date | Thu, 16 Aug 2018 08:15:59 -0600 | From | Keith Busch <> | Subject | Re: [PATCH v2] Bugfix for handling of shadow doorbell buffer. |
| |
On Wed, Aug 15, 2018 at 03:51:57PM -0700, Michal Wnukowski wrote: > 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; > }
Looks good to me. This should also be a stable candidate.
Reviewed-by: Keith Busch <keith.busch@intel.com>
| |