On Thu, Nov 22, 2018 at 04:53:34PM +0000, Chris Wilson wrote: > Quoting Daniel Vetter (2018-11-22 16:51:04) > > Just a bit of paranoia, since if we start pushing this deep into > > callchains it's hard to spot all places where an mmu notifier > > implementation might fail when it's not allowed to. > > Most callers could handle the failure correctly. It looks like the > failure was not propagated for convenience. I have no idea whether the mm is semantically ok if pte shootdown doesn't work for all sorts of strange reasons. From the commit that introduced the error code it souded like this was very much only ok in the limited case of an already killed process, in the oom killer path, where it's really only about trying to free any kind of memory. And where the process is gone already, so semantics of what exactly happens don't matter that much anymore. And even if a lot more paths could support some kind of error recovery (they'd need to restart stuff, at least for your i915 patch to work I think), as long as we have paths where that's not allowed I think it's good to catch any bugs where a nonzero errno is errornously returned. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
