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It is useful to teach lockdep that memory cannot > > > > be allocated on these workqueues. Add an interface to taint workqueue > > > > lockdep with reclaim. > > > > > > Oh that is so wonderfully evil. I'm absolutely in favor of doing this. > > > > > > But can't we check for the existing WQ_MEM_RECLAIM flag in the workqueue handling instead? > > > > > > > Tejun suggested tying the lockdep annotation to WQ_MEM_RECLAIM, but the > > entire kernel explodes because many workqueues throughout Linux don’t > > adhere to this rule. Here's a link to my latest reply to Tejun [1]. > > How about making it a WQ flag? > That could work too. We want to enforce rules of drivers actually set these flags setting passing workqueues to the DRM scheduler. Any objection to adding helpers to the workqueue layer to fish the information we'd like to enforce? Matt > Thanks. > > -- > tejun