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>> + >> + spin_lock_irqsave(&psc_desc_lock, flags); > > Would it be simpler to just do a spin_trylock_irqsave()? You fall back > to early_set_pages_state() whenever you can't acquire the lock. I was looking at that and can definitely go that route if this approach is preferred. Thanks, Tom > > That avoids even having to know what the situations are where you > _might_ recurse. If it recurses, the trylock will just naturally fail. > You simply can't have bugs where the "(in_nmi() || !ghcb_percpu_ready)" > conditional was wrong.