Messages in this thread | | | Subject | Re: [PATCH] IB/mthca: Fix how mthca_map_user_db() calls gup | From | Doug Ledford <> | Date | Fri, 26 Jan 2018 10:44:28 -0500 |
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On Thu, 2018-01-25 at 11:27 -0800, Davidlohr Bueso wrote: > On Thu, 25 Jan 2018, Jason Gunthorpe wrote: > > > > > > > Since the original post was referred to an ABBA deadlock, wouldn't we > > > have to drop db_tab->mutex, then grab both in the proper order? > > > > I had understood that was only a concern because Davidlohr was having > > trouble proving the callchain didn't include mmap_sem already.. > > > > I can see the call chain all ends on verbs ops, and I know verbs ops > > with ucontext's are never called under mmap_sem by the core code.. > > Right. Ok so this simplifies things and we can just use gup_fast(). > > Thanks, > Davidlohr
Thanks, applied.
-- Doug Ledford <dledford@redhat.com> GPG KeyID: B826A3330E572FDD Key fingerprint = AE6B 1BDA 122B 23B4 265B 1274 B826 A333 0E57 2FDD[unhandled content-type:application/pgp-signature] | |