On Sat, Jul 11, 2015 at 03:17:36AM -0700, 'Christoph Hellwig' wrote: > On Fri, Jul 10, 2015 at 01:54:20PM -0600, Jason Gunthorpe wrote: > > diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c > > index bac3fb406a74..6ed7e0f6c162 100644 > > +++ b/drivers/infiniband/core/verbs.c > > @@ -1126,6 +1126,12 @@ struct ib_mr *ib_get_dma_mr(struct ib_pd *pd, int mr_access_flags) > > struct ib_mr *mr; > > int err; > > > > + /* Granting remote access to the physical MR is a security hole, don't > > + do it. */ > > + WARN_ON_ONCE(mr_access_flags & > > + (IB_ACCESS_REMOTE_WRITE | IB_ACCESS_REMOTE_READ | > > + IB_ACCESS_REMOTE_ATOMIC)); > > + > > How about providing a system-wide IB_ACCESS_LOCAL_READ | > IB_ACCESS_LOCAL_WRITE MR that all drivers can use and get rid of > ib_get_dma_mr in the long run? That would help to nicely simplify > drivers? That is more or less what I was talking about when I suggested removing the lkey from the API ULPs use. Ultimately ib_get_dma_mr is just one call, and switching to (eg) pd->local_memory_lkey is tidier, but not much simpler.. > Currently various drivers are using ib_get_dma_mr with remote flags > unfortunately, e.g. the SRP initiator driver uses it to optimize away > memory registrtions for single SGL entry requests. Unconditionally? Ugh. Maybe we do need the warn_on :( > That looks fixable realtively easily, but I don't understand the > other consumers as good. The ones I looked at used it as a fallback if FMR or FRMR are not available. Jason -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
